texts: Was this a successful deployment of an MD-88 tail cone evacuation slide?

texts:
In this video, the tail cone is popped off as part of the evacuation.

It stays attached on a lanyard which seems to be more of a hazard than letting it fall free.  Additionally, the slide doesn't deploy.

It's clear that the rear and front port exits are the safe ones, but did something go wrong here?

(P.S.  I'm not talking about the actions of the pax, just about the tail slide).


texts: Is a cIearance only valid once it's accepted?

texts:
I've read somewhere that "a clearance is not valid until read back correctly," but I can't remember where or find a specific rule saying that.

I understand some clearances can be accepted with "Wilco" or similar in lieu of a full readback, but assume this isn't one of those cases.

For example, is it technically a violation to cross the runway hold bars before you finish reading back a takeoff or crossing clearance?


texts: What factors come into play when reducing the total noise generated by a helicopter?

texts: I simply cannot understand how a helicopter can be made quieter. What are the things that would considerably affect the noise signature of a helicopter ?


texts: How much money can be saved by removing seats?

texts:
If have an airbus A380, and I remove 500 of the seats entirely from the airplane (Along with their overhead compartments), and the remaining 300 or so seats I fill up normally with people, is the MPG of Kerosene used by the plane substantially different?
Basically, assuming airlines could do it quickly (which right now they can't) would removing seats and overhead compartments from the plane be a substantial way to reduce costs on empty planes?
The limit of this question is also something I'm curious about. If I have an Airbus A380 completely stripped of seats and overhead compartments, how much better is its MPG compared to a normal one filled with people and baggage?


texts: Is there any limit to how many times an aircraft evacuation slide may be deployed?

texts: I've seen multiple videos online of evacuation slide tests and they all tend to be almost violent as they are very fast and loud, but I can't help thinking that it must put a lot of force on those seams when they inflate and along with that the material. Is there any limit to how many times these may be deployed before they must be retired?


texts: What is the length of the escape rope in the cockpit? specifically A330-300 (If possible)

texts: I understand you could measure from height of the cockpit window, but is there any official dimensions stated anywhere such as FCOM or FCTM documents?


texts: What does "With One Minute Weather" Mean?

texts:
Yesterday I was listening to LiveATC at McClellan Field (KMCC) since many CAL Fire Tankers are stationed there and there's a lot of activity recently.

As the tankers returned from their bombing runs, they called McClellan Tower and reported they had the "One Minute Weather".

Most seemed to be flying VFR if that matters, although the Tower was handing out Squawk codes to those that requested them (on departure, probably for better TCAS reporting, coordination and general awareness I presume).

I'm unfamiliar with the weather report "with one minute weather", what does it mean? Is it a quick way to report they have the latest ATIS information?


texts: Is there a name for change in attitude with respect to time?

texts:
I'm in the process of writing a flight-dynamics software program, but I'm not sure what to call the derivatives of the aircraft attitude. If it was in one dimension, they would be the "angular velocity" and "angular acceleration" respectively.

In aviation, is there a special name for these vectors?


texts: Why did the US Airways Flight 1549 passengers stay on the wings?

texts: Couldn't they use the overwing slides as flotation devices and stay on those instead?


texts: Why select the transponder to TA only in the case of engine failure?

texts:
Part of the 777 engine failure checklist is to set the transponder to TA only.

What is the purpose of this step?


texts: Was the 737-300's wing an early supercritical wing?

texts:
I know that the 737 NG borrows the basic wing design of the 777, but I have also heard that BAC 4xx airfoil on the 737 classic (300/400/500) was an early supercritical aerofoil design?

Is this true?


texts: How is a wing designed to be stall or spin proof?

texts:
Yeah, it sounds like two questions, but I suspect the answers are very closely linked (or maybe even have the same answer.)  I was told in this question that trainer planes are often designed to be stall or spin resistent.  I was wondering how this is accomplished?

How does one make a wing resistant to stalls or spins?  Or perhaps, more generally, how does one make a wing predictable and stable?


texts: Is a FAA certified plane allowed to fly everywhere in the world?

texts:
Following the debate about FAA and Boeing certification practices,  I was wondering whether Europe could potentially require the Boeing 737 Max to be certified by a European agency.
Is a FAA certificate de facto valid in other countries ? Or are all planes required to be certified by local authorities too ?

Update :
Despite FAA certification being valid throughout the world, it appears EASA will conduct its own review of the fixes implemented by Boeing.
It is not a proper re-certification, but the plane will have to comply with EASA in order to be able to fly again in the European airspace.
More about this here (FT paywall).


texts: Why do similar Airbus and Boeing aircraft use different flap and slat mechanisms?

texts: Why do most Boeing aircraft and their corresponding Airbus counterparts have different flaps and slats mechanisms (747 and A380, 737 and A320)? I'm assuming a lot of these mechanisms are patented. For example, the 747 is equipped with Krueger flaps while the A380 has the leading edge droop as slats.


texts: How do the shockwaves (supersonic and hypersonic) interact with the structure?

texts:
My main question is why spaceplanes are conceptualized as pointy and lengthy, dart-like machines. What would happen if they were more like flying wing?
I'm hypothesizing a bit and I am not sure what would happen if a flying wing type of aircraft (most notable example B-2) were to go supersonic or hypersonic. So let's push B-2 to Mach 20.
How would the shockwaves interact with the structure? Would they remain oblique within supersonic regime (a)? Would they transform into bow shockwaves in hypersonic or cross the structure (b)?


texts: What is the MaNE for the CF-100 Canuck, I'm doing a case study for that plane and need to find the VmaNE (Vmax Never Exceed).


texts: How do you determine the lift coefficient of a finite wing using the coefficient of an infinite one?

texts:
How assuming I know the lift coefficient of an airfoil/infinite wing, how do I then use this value to calculate the lift coefficient of a finite wing? Please quote your sources.

Many thanks,


texts: Do you need to have a raft if you're in a seaplane?

texts: One of the basic rules of flying over water is that you need some kind of raft if you're out of power-off glide range from land. Does that also apply to seaplanes or amphibious planes?


texts: Is it possible to extend an AFSP training request?

texts: My training request expires in a week or so. Is it possible to extend it or do I have to submit a new one if I'm running out of time?


texts: Is the combustion process in turbofans and turboshafts different?

texts:
According to a journal paper, for a Gnome turboshaft engine, fuel-air equivalence ratio decreases as power output increases. However, for a CFM56 turbofan engine, the opposite trend is true, and equivalence ratio increases as engine thrust increases.

Why is there such a difference between these two types of turbine engines?


texts: What is the difference between a crabbed and de-crab landing?

texts: Both landings are done when an airplane's nose is not in inline with the runway. How are these two different? when should one technique be preferred over other?


texts: Why did the 747-8's freighter version make its first flight before the passenger version?

texts:
I have read that the 747-8F entered service in October 2011, almost eight months ahead of the passenger version (747-8I).

Anyone know why this is?

Thanks


texts: What kind of airplane is this that has blue cheatlines and a protruding side cover?

texts:
Consider:

Which airplane is this? I suspect it is Russian, but it's too poor quality for me to tell. I'm pretty sure it is military.


texts: What does "representative sample engine" mean for an overhaul extension?

texts: If the PT6 turbo prop engine is required for an extension for overhauling due to operational reasons, the manual has to be searched if the extension is feasible for the company. The company states that for the overhaul extension to be carried out a "representative sample engine" is required. What does a representative sample engine mean? Does it specify a part of the engine to be sent to check if the extension is feasible?


texts: Is there simpler way than scraping flightradar to determine Number of Flights between Two Countries?

texts:
Is there a simple way to procedurally determine how many flights are flown between two countries on a given day?  Maybe even get an inbound/outbound break down?

I consulted the FAA data site (https://www.faa.gov/data_research/aviation_data_statistics/) but I didn't find anything promising.  I was also considering scraping flight radar (https://www.flightradar24.com/) but is a somewhat complicated endeavor.  Is there a simpler solution?


texts: What is the maximum slope for taxiing aircraft?

texts:
Every airport I have encountered has flat runways and taxiways.

Of course this is not exactly true, as some other questions picked up, and it is also possible that I just happened to visit mostly flat airports.

Is there any specification for maximum slope gradient an aircraft can safely taxi on?

A slope could be useful if an airport wanted to build an airplane bridge for example.


texts: Am I required to obtain a student license before a sport, recreational, or private one?

texts:
I want to double check if my first step in obtaining a sport, recreational, or private license is to obtain a student license.  I'm assuming student license always comes first, but want to make sure.  :-)

I want to make sure that isn't a less expensive way to go than this -- jumping into a more intensive program to go "straight" to the higher level licenses.  Want to make sure getting a student license first doesn't financially waste some of the classes, training, or flight hours you pay for -- by them not counting toward the higher level licenses -- where if you had done it differently you would have saved money.

I'm not talking about less learning, just how it's done.  (Making sure high enough licensed instructors, right classes, etc.)

As an addition... Do you jump through student, sport, recreational, to private?  Or, do you go from student which whichever of these you want?


texts: What is the difference between a loss of control and an upset? From what I have read, first, an upset occurs, which leads to a loss of control (LOC). But, when can one say that the upset has been transformed into a LOC?


texts: How does a VOR or a VORDME affect the coding decision between CF or IF-TF respectively?

texts:
I was reading of the following case in ARINC 424-17 spec. Unfortunately the image is copyrighted and I can't paste it here, so here is a low(er) quality image of mine replicating the situation:

The text says that the path after the VI has to be coded as a CF if the XYZ is a VORDME but if the navaid is VOR only then it should be an IF-TF sequence. My question is not why is that sequence by how does the collocated DME affect the decision? The document mentions

This will allow a segment to be constructed, from one fix to the next fix, using an “intercept” where coding would otherwise not be possible.

But it doesn't explain why is it "not possible" to code this path as a CF if the station doesn't have DME. How does DME help here? In my mind, FOOBR is on a radial, let's say 55 from XYZ so if the airplane intercepts and follows this radial it will arrive to FOOBR, no DME involved. Is there something that I'm missing here?

VI vector to intercept
CF course to fix
IF initial fix
TF track to fix
Clarification:
Ralph J asked "what's the difference between CF and TF paths?" That's actually a good question. The spec is quite laconic:

Course to a Fix or CF Leg. Defines a specified course to a specific database fix.
Track to a Fix or TF Leg. Defines a great circle track over ground between two known databases fixes.

To my understanding, TF is more accurate as the course is derived from the previous fix while CF requires the course and recommended navaid to be coded in the aircraft's database, hence making the TF a simpler choice when available.


texts: who owns the abbreviated name of an airport

texts: is the name of an airport such as LAX the act of the FAA or the ICAO?  from reading, it looks as though the process starts at the ICAO as a recommendation, then is adopted by the FAA?


texts: Why do airports in the UK have so few runways?

texts:
Almost all of the major airports in the United Kingdom are single-runway (or functionally-single-runway) installations, with only two of the very busiest (Heathrow and Manchester) having as many as two runways (although Heathrow has a third under construction).

(In addition, even for the three major UK airports that have two runways, the two runways are always a parallel set, with no provision made for crosswind operations.)

This is - with few exceptions - far fewer runways than would be normal for airports of their size.  Taking the seven airports in the UK with more than ten megaemplanements in 2018 and comparing them to similarly-sized airports elsewhere:

Heathrow (two runways, with a third under construction) v. O'Hare (seven runways, with an eighth under construction)
Gatwick (two [functionally one] runways) v. Newark (three runways)
Manchester (two runways) v. la Guardia (okay, two runways)
Stansted (one runway) v. Baltimore-Washington (two air carrier runways1)
Luton (one runway) v. Calgary (four runways)
Edinburgh (one runway) v. Norman Mineta (two runways)
Birmingham (one runway) v. Raleigh-Durham (two air carrier runways1)

Having so few runways not only increases congestion and severely limits the number of flights that can use the airport without infringing on safe separation distances between aircraft, but also poses the risk, for the four single-runway airports,2 of an unserviceable runway (for instance, due to snowplows, potholes, trespassers, flocks of birds, wayward deer, or a disabled aircraft) shutting down the entire airport, potentially for a prolonged period of time.

Why do the UK's major airports have so few runways compared to the norms for airports of their sizes?

1: Plus one general-aviation runway each for Baltimore-Washington and Raleigh-Durham.

2: And, to a lesser degree, for functionally-single-runway Gatwick, as its emergency backup runway is close enough to the main runway for a single debris event to potentially affect both.


texts: What happens to the dynamic temperature in the boundary layer at supersonic speed?

texts:
In the boundary layer for a supersonic flow, does the dynamic temp decrease?
Thank you


texts: Why did Lockheed Martin give the F-22 stealth fighter such small fuel tanks?

texts: Why did Lockheed Martin give the F-22 stealth fighter such small fuel tanks while the F-35 got much more fuel capacity relative to its size and single jet engine?


texts: What options do pilots and mechanics have when an aircraft owner doesn't pay up?

texts:
If someone does a contract flight, or a mechanic does contract maintenance for an aircraft owner and they refuse to pay after the fact, what options do they have to "encourage" the owner to pay?

One of the big problems is that this tends to happen informally:

  Owner: "Hey, can you do this flight for me?"
  Pilot: "Sure, I charge $xxx." "
  Owner: "Okay, great.  See you on Monday morning at 9:00."
  Pilot: "Sounds good, see you then."

So they show up, do the flight, send an invoice, and wait.  And wait..  And wait....  After a few weeks or 30 days, they send the invoice again.  Give it a bit and make a phone call.  Eventually it becomes clear that they just aren't that interested in paying a lone individual without the typical resources of a larger company.  Unfortunately, this happens more than you would think in this industry.

It probably isn't enough money to actually go out and hire a lawyer for, but it's irritating and they want their money.  It's the principle!  I've heard of people placing a lien against the aircraft.  Is that something that an individual can do, or do you have to hire a lawyer?  Is small claims court an option?

I'm looking for an answer that describes general approaches that can be taken, as obviously specific legal advice cannot be given without details of a situation like this.


texts: What is the white pattern on trim wheel for?

texts:
On a A320, there are white patterns spread regularly on the trim wheel (highlighted on the right of the picture). First I though it was to have visual feedback about THS (trimable horizontal plane) position. But looking closely, this role seems to be played by the graduations (highlighted on the left of the picture).

(photo #0393544 from airliners.net)

Why are there those white patterns on the trim wheel? What is their role?


texts: Why do both east and west isogonic lines tilt toward the west as they go north?

texts:
Here is a picture of the 3 degree east isogonic line just north of Tulsa, OK.

Here is a picture of the 4 degree west isogonic line just east of Nashville, TN.

They both trend westward in relation to true north as you follow the lines northward.  Why do they not go in opposite directions if one is to the east and the other to the west?  This also implies that the 0 degree isogonic line is not parallel to true north.

I checked, and sure enough, it also goes west as you follow it to the north.

Why don't the lines tilt in different directions after crossing over from zero degrees?


texts: Why are landing gear retraction mechanisms mostly based on the four bar system?

texts:
I would like to know about the principles of landing gear retraction system and I struggle to find clear information about it.

It seems to be about a four bar systems in most cases. This seems more complicated than necessary at first glance, why is a design with a simple hinge with an actuator that pulls the strut in not sufficient?

Most retraction retraction mechanisms involve a lot of pieces with complicated motions. I would like to understand the kinematics that justify the use of more than one or two bars. Intuitively, one would only expect an actuator acting directly on the landing gear, holding it into position, but the reality always involves complex rotational kinematics.

This question would also apply to the kinematics of flap tracks, which seem to be fairly complex as well.


texts: Are larger airplanes more likely to stall?

texts:
Stalls happen when the boundary layer on top of a wing slows so much that it essentially becomes part of the airfoil.

My question is, as the wings on larger aircraft present a longer flow path for the boundary layer, they slow the layer more. Right? So, would they not be more have a lower stall angle? Isn't this what is hinted at by the use of slots on airliner flaps?


texts: How can I estimate wind speed and direction in VFR?

texts:
I am new here, I started to do VFR navigation (no G1000) so I try to deal with the wind.
I notice that I have some problems to find the wind speed and direction during flight. I am going to try to explain better: I am looking for some easy method to find the values (for example no CRP5 or too long trigonometry formula), something that can give me a fast idea from where the wind is blowing and the speed so I can anticipate the correction.


texts: Is a night VFR rating a prerequisite for an EASA CPL?

texts: I'm wondering if I need to pay for a night VFR (NVFR) rating or can I just do my time building, ME, IR and exams to get a CPL? Is it possible without an NVFR rating?


texts: How to compute the change in static temperature using only altitude?

texts:
I'm given an initial altitude of FL290 in ISA conditions, and the aircaft is said to climb to reach FL310. How can I use this to calculate the change in static temperature between the two flight levels?

I know that the formal term is the lapse rate and generally lapse rate decreases around 2 degrees Celsius per 1000 feet of climb.

Would I use a ISA temperature table to figure out the temperature for the initial altitude and then use the lapse rate to calculate the change in temperature when it climbs to reach FL310?


texts: with a runway 9/27 I am approaching from the east travelling in a westerly direction will I land at the 9 end or the 27 end?  in other words, is the number on the end the compass heading or the direction of travel?


texts: Are there specific engine TBO requirements for aircraft used in flight instruction?

texts:
If I own a plane, say a Piper arrow, and I want to charge 175/hr for the aircraft and 50/hr for instruction, is there any regulation on when to perform engine overhauls (TBO)?
askacfi.com and avweb.com indicate no TBO requirements.
However, 14 CFR Subchapter G - Air Carriers and Operators for Compensation or Hire: Certification and Operations may indicate I do.
What specific regulations show what is or is not required?


texts: How are the TRACON location IDs determined?

texts:
Most of the TRACONs in the US are colocated with a control tower. The location IDs of these match their airport IDs, which makes sense.

There are also several TRACONs that are not located at a control tower. Most of these are designated with a letter and two numbers, such as A11 for Anchorage. The first letter usually matches the TRACON name, but not always. Where did these IDs come from? Does the number signify anything?

Also, there are a few of these non-tower TRACONs that use three letters and no number - what makes them special?


texts: Is medical certification required for flight attendents?

texts:
In the history of stewardesses: "In the earliest days of commercial flight, there were teenage cabin boys, and the first female stewardesses had to be registered nurses."

The 2009 book Flying Across America: The Airline Passenger Experience by Daniel L. Rust says, "*Dressed in hospital whites or military-style uniforms, a 'sky girl' of the 1930s not only served meals and soothed nerves...*

Is any type of medical certification required for flight attendants in the US or other parts of the world?


texts:
Airbridges slow boarding and disembarking because (normally) there's only one door in use. But... why?

Now the most obvious reason would be that it's very easy to have the aircraft pull forward until its door is roughly in line with the bridge, while it's not possible to do that at the back as well, given the differences in fuselage length.

Sure, but I suspect that 90% of all aircraft could be serviced from a set of two possible bridge locations and the existing bridge movement range.

And then one notes that the wing would be an issue, but that's only true if the bridge is in the air. One could just as easily build a "bridge" on the surface, or even underground (I saw a cross-section of the ramp at Pearson, it was like swiss cheese).

Of course that would mean walking down stairs, which is one of the reasons you use a bridge in the first place, but it would mean that anyone with normal capabilities could use it without exiting outside (did that at Pearson too, in the middle of winter).

Such a system would have the added advantage of allowing the Spanish Solution, with three waves, the middle being the cleaning crew.


texts: Can a plane help a second aircraft with landing gear issue mid-air?

texts:
My Father received his flight training in the Navy in 1941. He flew mostly Curtiss Wright SNC's (a model of the CW-22) and Grumman F3F's. The story I was told is hard to believe, so I'm hoping that some of you pilots out there (I'm not one) can tell me if this kind of stuff really happened.

While returning from a training run and preparing to land in an SNC, one landing gear would not go down. A second plane pulled alongside my Father's plane and with its wing tried to knock the landing gear loose! While in mid-air!

I find this hard to believe, but hey, you never know.

Many thanks for any insights!

td


texts: What is needed to take off in CAT IIIb weather and how is it done?

texts:
Landing is possible down to 150 ft visibility and no useful vertical visibility using CAT IIIb ILS. This relies on ILS not only for navigating to the runway, but also for maintaining runway centreline during roll out down to taxi speed.

So is it also possible to take off in such weather and if so, how is it done?

(edit) Answer to Who authorizes low visibility takeoff operations for airlines, and what is required? mentions take off is possible down to 300 ft RVR with a "takeoff guidance system". So more specifically, how does that work?


texts: Who is responsible for aircraft separation in IFR (limited/no visibility)?

texts:
I was reading how-much-is-the-minimum-safe-distance-between-two-planes-in-flight and realized part of it confused me (or maybe I'm just tired.)
In a low- or no-visibility environment (i.e. under IFR rules AND conditions), who is responsible for separation of planes in flight?
§91.111 Operating near other aircraft and §91.13 Careless or reckless operation are both shown in that question/answer, but if a flight is under ATC guidance, are they (ATC) or the Pilot-In-Command (PIC) responsible?
I'm most interested in the U.S. (FAA Regs), but discussions of other regulatory bodies would be fine.


texts: Where did the standard pressure 29.92" come from?

texts:
Below the transition altitude (18,000 feet in the US), pilots use local pressure readings to calibrate their altimeters.

Above the transition altitude, pilots set a standard pressure to calibrate the altimeter. The standard pressure is 29.92 inches of mercury or 1013 hPa.

Where did this value come from?


texts: Can an experienced airplane spotter identify planes only by sound?

texts:
I come from a background in railroad watching, and often times one can identify the maker of a railroad locomotive purely by sound.  Maybe not the exact model of locomotive, but at least what type of diesel engine is in the locomotive.

Although there is a similar question here: What could cause GE and Rolls-Royce turbofan engines to sound different?, my question is whether an experienced airplane spotter could be near the end of a runway at a busy commercial airport and be successful in identifying the model of commercial jet aircraft landing and taking off only by the sound the spotter is hearing from the aircraft as it flies overhead?

To me as an inexperienced airplane spotter, they all sound similar.  But to airplane spotters, all railroad locomotives may sound the same too.  :-)


texts: Does dihedral improve roll stability in gusty conditions?

texts:
Against roll instability, should I add more dihedral/a high wing?
I'm trying to build an RC plane that can handle windy conditions. For that I want extraordinary aerodynamic stability.
For longitudinal static stability, I make my planes quite nose-heavy, and compensate for that with a greater tail downforce. That works.
What doesn't work is lateral stability/roll stability. In theory, if a gust rolls my airplane, I will have a sideslip. Due to a high-wing configuration, and a dihedral angle, I will have a rolling moment that will counteract the original roll angle.
Image from avstop.com, modified

So I made my plane attempts have great dihedral/polihedral angles, and a really high wing with a solid surface underneath to further help counteract any rolling.

Any time I went crazy on dihedral and high wings, my planes kept crashing agressively due to very sudden and very powerful side/back flips. At first I didn't understand, as these features should've made my plane almost un-rollable.
However, what I suspect is that these features had the opposite effect. Correct me if I'm wrong, but looking a the first diagram, what I see is that when a plane flying at level flight encounters a sideways gust, it will also make the plane agressively roll over, just as if the sideways gust was from a roll induced sideslip.
Is this a correct assessment? Did these roll stability features make my planes roll around uncontrollably?
Is there a way to have my plane react normally to a sideways gust while having static roll stability? Do I need way bigger vertical stabilizers for these dihedral values?


texts: Which country has jurisdiction over incidents in flight?

texts: If an incident occurs on board an aircraft in flight which could be considered as criminal in one country, what decides which country the incident falls under? For example, if a man was found to be in possession of "virtual" child pornography and not all of the countries involved consider that to be illegal, which country is the one who decides whether the person have broken the law or not?


texts: Do LED lights work well for CAT III B operations?

texts:
Does any airport equipped with LED lights for all the CATIII B Components? If so, is there any history that it caused difficulty in aircraft operations?

We are planning to install our new runway with CAT III B lighting with LED fitments.


texts: Why isn't runway 4L/22R at KMDW available as an emergency runway?

texts:
Chicago-Midway (MDW/KMDW) has five runways, oriented along the diagonals of the square airport.  The longest two (13C/31C [1988 x 46 m] and 4R/22L [1964 x 46 m]) are ILS-equipped, and serve as the airport's primary air carrier runways; the other three (4L/22R, 13L/31R, and 13R/31L) are used primarily for small general-aviation operations.  Of the three, 13L/31R and 13R/31L are available for use by larger aircraft in case of emergency:

  Chicago Midway International Airport covers just over one square mile (650 acres or 260 hectares) [...] and has five runways: [...]

  13C/31C: 6,522 ft × 150 ft (1,988 m × 46 m), air carrier runway, ILS-equipped.
  4R/22L: 6,445 ft × 150 ft (1,964 m × 46 m), air carrier runway, ILS-equipped.
  4L/22R: 5,507 ft × 150 ft (1,679 m × 46 m), general aviation and air taxi.
  13L/31R: 5,141 ft × 150 ft (1,567 m × 46 m), general aviation and air taxi. Used as an Emergency Runway for commercial aircraft.
  13R/31L: 3,859 ft × 60 ft (1,176 m × 18 m), light aircraft only. Used as an Emergency Runway for commercial aircraft.

4L/22R, however, is apparently not available for use by air carrier aircraft even in an emergency, despite being longer than either of the other two general-aviation runways (and also twice and half again as wide as 13R/31L, the smallest runway at the airport), and the only one of the three to be useable when the winds are blowing along a northeast-southwest axis (the two designated emergency runways are both oriented northwest-southeast).

Why are Midway's two smallest runways available as emergency runways for large aircraft, but not the larger 4L/22R?

EDIT: As @RonBeyer suggests in his comment, one potential reason a runway of sufficient size might be unuseable for large aircraft could be if its bearing strength were insufficient (such that the pavement could collapse under the weight of a heavily-loaded jetliner).  However, to hear it straight from the horse's mouth, 4L/22R is rated for aircraft imposing pavement loads of up to 30 short tons per single wheel, or 60 short tons per two-wheel bogie; although not up to the standards of the airport's two air carrier runways (each rated to 47.5 short tons per single wheel, 82.5 short tons per two-wheel bogie, or 125 short tons per four-wheel bogie) or emergency runway 13L/31R (rated to 40 short tons per single wheel, or 62.5 short tons per two-wheel bogie), it far surpasses the mediocre strength of runway 13R/31L, which is rated for a mere 6.25 short tons per single wheel... and is, nevertheless, a designated air-carrier emergency runway!


texts: Can airliners operate without an operating APU?

texts:
As the APU (Auxiliary Power Unit) can be turned off when the engines are running, a functional APU may not be needed given you are able to start at least one engine. This question is in two parts:

Is it technically feasible to operate an airliner without APU (with the necessary ground support)?
If so, in what conditions is it legal (number of passengers transported, MEL, test flight,...)?

This question focuses on airliners. If needed, it can be narrowed to best-sellers (B737 and A320).


texts: What's holding equipment manufacturers from going into multicore, RTOS-based equipment?

texts:
What's holding equipment manufacturers from going into multicore, RTOS- based equipment?

Recently, Rockwell Collins certified its display systems based on RTOS:

Lynx Software Technologies, LynxOS-178 RTOS Deployed by Rockwell Collins in Pro Line Fusion Series of Flight Deck Systems, November 27, 2012.

Why are major players not moving into these segments like RTOS, multicore processor? Is it because of certification difficulties?


texts: Is there a special procedure for mid-air refueling in the rain?

texts:
After reading about mid-air refueling and watching The Perfect Storm, I have a question: is there a special procedure to observe when performing an in-flight refueling in the rain?

Side note: I heard the tanker pilot says something like "we have a wet hose". Is this phrase common?


texts:
This probably sounds like a silly question, but I was watching floatplanes land on Lake Union, Seattle, and it got me wondering whether a plane that touches down onto water is still talked about as "landing" in aviation parlance.

Is it?


texts: Can the TSA require supplemental screening AFTER a flight has landed?

texts:
A few days ago, Kahler Nygard reportedly received a boarding pass indicating secondary screening was required, but that pat-down was reportedly never done. So when the plane landed, they took the passenger off the plane ahead of the others and requested that he submit to the screening at the destination airport, after the flight. He recorded the incident on his phone, and after confirming that he wasn't being detained, simply walked away.

The proposition that screening a passenger after the flight has landed might retroactively increase the fight's safety is, I think we can all agree, counter to the fundamental nature of causality.

But the question is this: Is screening passengers after they have arrived at their destination without incident within the rights and responsibilities of the TSA? Clearly it doesn't jive with the whole "cause and effect" framework of reality that we all live in, but are they within their rights to demand such screening anyway?


texts: What is the process for converting a US certificate to a Japanese license?

texts:
I have a Japanese exchange student (here for at least 4 years) who is looking to pursue a pilot's certificate (up through commercial, potentially to an ATP rating) in the US and, upon returning to Japan, convert it into Japanese ratings and licenses and try to get into the airlines.

I'm trying to give him an idea of how difficult or not it is to make that happen, and what hoops he might need to jump through.  Google has only led me to outdated forums and websites, so I thought I'd give it a go here.

How do you convert a given US pilot's certificate (private pilot, commercial, ATP and ratings including instrument, etc.) to a Japanese license?


texts: Can airliners land with auto pilot in gusty wind conditions?

texts:
Why does the pilot make so many movements? I don't see that plane is moving all that much, but his yoke movements are strong and fast.
For someone who is not a pilot, it almost looks like panicked flying.

Can airliners land with auto pilot during the day with strong winds and does night make landing even worse in these gusty conditions?


texts: Do airline pilots use FD when performing visual landing?

texts: Permitting weather, most airline pilots get visual landing clearance in the US, unless they specifically have requested an instrument or RNAV approach due to their company rules or special circumstances. My question is: when they disengage Auto Pilot for visual landing, do they still use Flight Director until short final?


texts: Can a sonic boom produced at 60,000' be heard on the ground?

texts: The Concorde normally cruised at an altitude of 55-60,000 feet, but wasn't allowed to fly over populated areas due to the noise it produces. Can the sonic boom of an aircraft at 60,000 feet be heard on the ground?


texts: What is the maximum altitude allowed to fly a model plane/helicopter in England?

texts: What is the maximum altitude I'm allowed to fly a model plane or helicopter in England?


texts: What are the differences between air brakes, spoilers and lift dumpers?

texts:
So many people use these words interchangeably, but after a little searching on Google, I found they are not quite the same thing. All the links I read explain things in a misleading way which pushed my confusion even further.

I'm looking for a simple explanation on the effect of these parts on The Four Forces of Flight


texts: What effect do urban wind conditions have on operating tiltwing aircraft and gyrocopters?

texts:
From this research it seems there are quite a lot of strong wind in suburb residential area and around high-rise buildings. High-rise buildings would also create wind tunnel effect and eddy winds.
When trying to land or takeoff in heliports, or rooftop helicopter pads, would the wind cause the tilt wing or tilt rotor aircraft to flip or move around? Would the wind big enough that when the wing rotated 90 degree, the wind could push the aircraft away from the desire landing spot?
If it is a gyrocopter, would the rush of city wind, or even the eddy wind, drive the top rotor harder so the landing or takeoff becomes an issue?


texts: Can I do an instrument rating checkride in an experimental aircraft?

texts:
The EAA has a document that strongly suggests that IFR operation in Experimental Aircraft is legal.  The necessary equipment is described in 91.205.  Provided all this is met, as well as all other IFR requirements (e.g., pitot check, appropriate engine, etc.), I think instrument rated pilots are ok to fly IFR in an experimental.

However, in a question related to a checkride in an LSA, Can I do an IFR checkride in an airplane that isn't certified for IMC? , I learned about another concerning aspect.  It says:

  the Instrument Practical Test Standards (FAA-S-8081-4E PTS Instrument):  Aircraft and Equipment Required for the Practical Test The instrument rating applicant is required by 14 CFR part 61 to provide an airworthy, certificated aircraft for use during the practical test.

[my boldface].  Putting all this together suggests that I can train and fly in true IMC in IFR in an experimental aircraft, but I cannot take my checkride in one.  Is this interpretation incorrect?  Are there (m)any cases in which checkrides were done in experimentals?

PS: I sometimes wonder whether we are training to become pilots or lawyers...


texts: Why did it take so long for helicopters to be developed/in use?

texts: The Sikorsky_H-5 was made in 1943 but used an engine released in the 1930's. It seems to me that the used that applied to helicopters, specifically in warfare, could have applied much earlier. Things like SAR, Medivac, spotting and ground support would all have been useful in the Second World War.


texts: On IMA systems e.g. A380 how many people are required to preform regular maintenance checks on this system?

texts: I am aware that there is usually 1 or 2 engineers preforming maintenance checks for a particular avionic system on an aircraft at a given moment. For IMA system, is there often more engineers working to get the maintenance checks completed. Are the maintenance check procedures/tests on IMA systems more complex that would require more people.


texts: Can I fly a "Contact Approach" to this airport?

texts:
In order to request and receive a clearance to conduct a "Contact Approach" the airport, among other requirements, must have a published instrument approach (IAP) and be reporting at least 1 mile visibility.

If the visibility being reported for this airport (Lake Tahoe -TVL)  is 2 miles, and thus below minimums for any IAP, would it be legal to conduct a "Contact Approach?"

(The two IAPs shown below are the only published approaches and the plates have been trimmed for brevity.)


texts: Why does the DHC-6 have only one set of elevator cables?

texts:
Air Moorea Flight 1121 crashed because its up-elevator cable broke, allowing the elevator to blow to its faired position and thus be unavailable to counteract the pitch-down moment caused by the flaps being retracted;1 the DHC-6 elevator control system has two cables (up-elevator and down-elevator, distinguished by what part of the aft-quadrant bellcrank they attach to), and, if one breaks, the tension in both is released and the elevator floats.  No redundancy is provided in the form of a second or third set of elevator cables, unlike how most airliners have double- or even triple-redundant flight controls.  Why does the DHC-6 have only a single set of elevator control cables, rather than two or three?

1: No matter that retracting one’s flaps should not do that.


texts: How do I fly a direct entry holding pattern when approaching from an awkward angle?

texts: If my course lies anywhere within 30 degrees adjacent to the 'direct entry' sector borders, do I fly the holding pattern as depicted below?


texts: Justification for the 2D cut-out method for determining a rocket's center of pressure

texts:
I've seen several tutorials on rocket stability where one can empirically obtain the center of pressure by cutting out a 2D imprint of the rocket and balancing the 2D shape as seen in the pictures below:

What is the physical/mathematical justification for this, otherwise, extremely simple method for determining center of pressure?  What are the underlying assumptions behid this method?  In what cases is it applicable?  When it is applicable, what order error should I expect from this method?  In what cases is it not applicable?


texts: Who is responsible - CFII or the Private Pilot?

texts:
Here's the scenario: There is a Private Pilot working on their instrument rating. Alongside with him is their CFII. Let's say it is just a normal VFR flight, and they're getting back to their home airport after a training flight. Now, after the first radio call, ATC instructs them "NXYZ, Squawk 1234 and ident - remain outside (Airport) Class Charlie".

Even though you just need Two-Way Radio Communications to enter Class C, ATC has strictly advised them to remain outside of it.

Now, for some reason, the airplane goes well inside Class C airspace. After a few minutes, ATC gives a call saying "NXYZ, cleared into Class C, enter left base Runway 18. Possible pilot deviation, advise when ready to copy down a phone number"

The question is - since both the Private Pilot and the Instructor are logging the flight time as PIC, who is responsible to answer? And if a deviation is given - who among the two gets it?


texts: What if pilot feels too tired before his flight?

texts:
Today is a day when I feel terribly tired. I'm not ill, but I could sleep all the day, though I had enough sleep last night.

This is not a problem if you have an office job where you can probably be not as productive than on other days. But what about pilots? They are expected to have a high level of concentration and vigilance during the whole flight?

This question, What should a pilot do if they feel sleepy? concentrates more on upcoming sleepiness during the flight. The accepted answer says:

  If a pilot is not rested enough to safely operate the aircraft, they should not fly. [...]

Well, "should not" sounds more like  advice than a rule.

You may say that there are always two pilots on (not so long) commercial flights, but then you can also start with one faulty engine, because the second engine still could bring you to your destination. For me, this breaks the safety concept.

So, can a pilot go to a doctor and tell, "I'm tired today so I can't work"?


texts: Empennage airfoils are usually symmetric. What is the process behind choosing the airfoil used in the tail of the airplane? Is it related to the stability? And then how would the angle of attack of the tail be determined?


texts: Supersonic propellers for supersonic aircraft?

texts: A propeller is a spinning wing. Supersonic wings work. So, provided that the blades are made wide-chord and thin like supersonic wings are, with a supersonic airfoil, can they not power efficiently a supersonic aircraft?


texts: How do I plan for my PPL checkride which will involve a diversion?

texts:
My CFI has told me that in my checkride I will begin a planned cross country flight and will be diverted to another airport shortly into the flight. My question is, how do I effectively plan for this? I am unable to get for example NOTAMS, weather predictions, runways and their lengths etc. for the airport I'm going to (because I don't know what it is)

From what I have read I will be acting as PIC on the checkride and as such I don't feel like I can comfortably satisfy CFR 91.103 when I don't even know where I will be flying to.


texts: Why aren't runways lit from overhead, like highways?

texts:
Why don't runways have overhead high-mast lights like roads? YouTube videos substantiate that

aircraft landing lights and runway edge lights are too faint to illuminate the whole runway, and
the runway is dark at night. But then how can pilots spot any physical obstacles on it?


texts: How quickly should a maneuver be started when ATC gives new heading?

texts:
This is going to be a no-brainer for a pilot, I am sure. I am not one, however, only an enthusiast.

Scenario is: I am flying under the directions of ATC, into a relatively busy Class-B airport and am given a change of heading by them.

  Piper N1234A, fly heading 235 ...

The radio is full of communications, and I cannot seem to be able to squeeze in to confirm receipt of heading change. I assume I would start the standard-rate turn immediately, and acknowledge as soon as possible, even if I've already completed the course change?


texts:
What are the policies on long flights and taking shifts sleeping between 2 pilots?
Could a pilot set the cruise control and alarm during any flight?


texts:
I found this picture earlier with a Lufthansa express livery:

It also appears to have been on a few larger aircraft like the A300:

Could somebody enlighten me as to what this operation was or the difference to mainline Lufthansa? I tried to search but couldn't find anything.


texts: Was Ludwig Wittgenstein's aircraft propeller ever built?

texts:
Ludwig Wittgenstein designed (and received a patent for, at the remarkable age of 22) an aeronautical propeller.

Wikipedia describes it:

  Wittgenstein’s design required air and gas to be forced along the propeller arms to combustion chambers on the end of each blade, where it was then compressed by the centrifugal force exerted by the revolving arms and ignited.

and adds:

  Propellers of the time were typically wood, whereas modern blades are made from pressed steel laminates as separate halves, which are then welded together. This gives the blade a hollow interior, and therefore creates an ideal pathway for the air and gas.

I've found some plans for this design, and some discussion of it, but it's not clear to me whether a working model was ever built, or attempted. I'd love to know whether it actually offered any advantage, or even whether it could be made to work with a reasonable degree of success.


texts: Does the validation of an ICAO licence allow you to fly internationally?

texts:
Hypothetical situation:
A pilot with an ICAO-compliant PPL licence from Australia goes to France and France issues a licence validation in accordance with the Chicago Convention, thus allowing him to fly aircraft registered in France.
If this pilot wants to take a French-registered aircraft to another country is this possible? From Article 33 of the chicago convention it seems like this should be allowed, but is it actually in practice?

Article 33
Recognition of certificates and licenses
Certificates of airworthiness and certificates of competency
and licenses issued or rendered valid by the contracting State
in which the aircraft is registered, shall be recognized as valid
by the other contracting States, provided that the requirements
under which such certificates or licences were issued or
rendered valid are equal to or above the minimum standards
which may be established from time to time pursuant to this
Convention.


texts: Would someone please describe or explain airship or zeppelin avionics packages

texts: I'm hoping to learn more about this avionics pictue, with a plan to redesign the user interface. Would someone be willing to share other pictures, along with descriptions of each data point?


texts: When should the term "pan-pan" be used instead of "Mayday"?

texts:
FAAO JO 7110.65, §10-1-1 states that "pan-pan" can be used to indicate a state of urgency:

a. An emergency can be either a Distress or an Urgency condition as defined in the "Pilot/Controller Glossary."
b. A pilot who encounters a Distress condition should declare an emergency by beginning the initial communication with the word "Mayday," preferably repeated three times. For an Urgency condition, the word "Pan-Pan" should be used in the same manner.

Under what conditions might a pilot use the phrase "pan-pan", versus "Mayday"?


texts: Are four-engined airplanes calibrated to put out the same thrust for both their inner and outer engines?

texts: Is there a slight difference baked into the aircraft's throttle control systems or are they always pumping out the exact same thrust as each other?


texts: What would happen if an airplane flew through a tornado?

texts:
I read a question which asked whether planes fly over hurricanes, so my question is what would happen if a low-flying commercial plane tried to fly through a tornado.

Assume that it's traveling at cruise speed.


texts: How to calculate the Glide Ratio from Drag & Lift?

texts:
I know that $c_{d}=0.03 + 0.095c_{l}^2$.

What is the glide ratio?


texts: Where to get flight dynamics for a flight sim model?

texts: Once, a while ago, I tried to create a Flight Simulator X model for an aircraft that I wanted a model of, but was soon overwhelmed by having to guess so much of the flight dynamics. Is there somewhere where I could get detailed information about the flight dynamics of aircraft without contacting the manufacturer, a pilot, or having the plane itself to run tests on? I mean for things like drag at different mach, drag coefficient created by the landing gear, lift coefficient created by the flaps, detailed stuff about the engines, etc.


texts: Is there a legal requirement to tell your doctor you are a pilot?

texts:
Specifically if I visit a doctor in Canada who is not a CAME for my regular aviation medical, do I have to tell him/her that I have a pilot's licence?

You can imagine why I'm asking.  I just explained to someone that I'm supposed to mention this to any doctor I see.  However, it's been ages since I've flown and I would no longer do this as I haven't even kept my medical up to date.

I've just searched the CARS and can't find any reference to this being a law.  Is it possible I was told this by mistake, or as something that's just recommended?  I do recall doing this once or twice and the doctor didn't just pat me on the back and say "good for you".  He nodded and just acted like it was a normal thing to be told.

Not sure what tags are available, but I'm interested in answers from other countries as well.


texts: Where can I find good data on volume of air traffic?

texts:
I want to have a look at air traffic fatalities data, and have found good information on number of accidents, like this on AviationSafety.

For comparison I want some (world-wide) data on passenger air traffic volume, like number of flights (journeys) per year, or passenger-km per year. So far I couldn't find it. Some good reference?


texts: Can a slow small plane, flying at a few meters above the ground, drop to the ground if the headwind abruptly stops?

texts:
Why do I ask this question? Because Wilbur Wright sent a letter to Georges Spratt (an aviation enthusiast he personally knew) saying that his plane, Flyer II, once in flight, accelerated easily to 45 mph, by itself, after reaching 30 mph. (The plane had no throttle.)
I know that once in flight, the airspeed of a plane is independent of the headwind, so it simply does not matter how fast the wind blows from in front of the apparatus. Those lulls in the wind Wilbur feared about would not have had an impact on the course of the aeroplane unless the wind suddenly dropped in intensity (this is more a theoretical case). Only then for a short time the airspeed of the plane decreases to its former airspeed minus the drop in the headwind speed, but the plane regains quickly its former airspeed.
The question is, can a low flying plane really touch the ground just because the intensity of the headwind diminishes?

We have made forty five starts with our 1904 Flyer. Unless the relative speed at starting is 27 miles in a calm and two or three miles more than that in a wind, the machine will gradually slow down till unable to fly. After the relative speed passes thirty miles the velocity accelerates till a relative speed of 45 to fifty miles is reached. We found it difficult in practice to get a speed down the track greater than 20 miles an hour, so that unless we had a wind of about 10 miles we were not sure of being able to fly for a lull in the wind would let us drop below the real flying limit. … We have now finished a starting apparatus which gives a speed at start of 27 miles an hour in a dead calm, and expect shortly to begin circling. (Wilbur Wright, “Letter to G. A. Spratt”, Dayton, Sep. 10, 1904)

Source Small plane flying at low altitude.
Update:
The topic Does a sudden drop of the velocity of the headwind affect the airspeed by lowering it? and its explanations do not answer my question. I was already aware that a sudden drop of the headwind intensity reduces for a short time the airspeed of a plane and I have already written this thing to make it clear I knew about this phenomenon.
The plane of Wilbur flew a few meters off the ground.
So, assuming Flyer II traveled at an airspeed of 30 mph against a headwind of 10 mph and suddenly the machine entered a region of perfect calm, its airspeed would have reduced to 20 mph instantly, but did the plane need to drop more than a few meters to regain its former airspeed of 30 mph?


texts: Are there conventions on which side to travel on Victor airways - USA?

texts:
I'm a low-time VFR pilot (100hrs) in the United States. I have not yet started IFR training (other than XC time building).

I understand the purposes and reasons why the Victor airways exist. I also understand the Victor airway widths are 8 NM minimum but widen when the VORs are further than 51 NM apart.

I regularly try to follow the Victor airways and VFR altitudes on VFR Cross Country flights, and do file VFR flight plans and use flight following. This makes it easier for me to communicate my position and seems it would be safer than just flying direct.

Question:

Is there a convention for a side of the "road" you should travel on in the USA?

My guess would be if a convention exists, it would be you should always travel on the right; this puts the red lights of the left wings of crossing traffic together, enforcing / encouraging avoid to the right; both A/C would make turns to the right, further expanding the horizontal gap between them. Right of way to the right, avoid to the right.

Background:

On a recent XC from KIXD to KSGF, I was traveling east at 5500' MSL and was directly over the radial, according to my GPS and my ODI. A west-bound crossing plane on VFR was at 6500' MSL and about 1 NM to the south of the airway. We both were using flight following and were alerted and there were no issues. But it made me pause to think, should I really be centered right on the radial? What if he were as well? Then there would be 0' horizontal separation, only 1000' vertical. And worse, if he were IFR at 6000' and right on the radial, that's even closer.


texts: Where could I find the FOD examples of C17?

texts: I want to find some FOD examples of huge planes in reason of ground vortex,where should I  go to search?


texts: 4 Boeing 707 for $50,000. Is that possible?

texts:
I'm helping a friend with an article on some issues in my country, mostly related to corruption. His English isn't very good, so here I go

One of the cases he's analyzing is the sale of 4 Boeing-707 airplanes for $50,000 . These airplanes couldn't fly but according to public information, they had their avionics, each of them has 4 working (not suitable for flying) Pratt & Whitney JT3D engines and one of them had a working intelligence/surveillance system (this was a very complex subject and now government says they'll try to keep this for training). Airplanes were for military use, both passengers and cargo.

Even considering selling them for scrap or replacement parts, is $50,000 a realistic price? For example, is there a place I can find prices for the parts, eg engines, landing gear and such?

EDIT: this is in Argentina, newspaper article (in Spanish).

Some data translated from article:

Approximate cruising speed: 977 km / h
Service ceiling: 11,000 meters
Approximate range: 8690 km
Empty weight: 62,500 kg
Load capacity: 94,000 pounds
Maximum operating weight: 335,600 pounds
It could carry up to 180 passengers

They are four-engine jet aircraft, Boeing brand.

Primary function: Transport of passengers and cargo, as the case may be.
Wing type: low implantation. Undercarriage: type retractable tricycle with 10 armed wheels. They have four Pratt & Whitney engines (turbines).
Length: 44 meters. Span: 47 meters. Tail height: 13 meters.

3 of the airplanes were bought by an US company specialized in airplanes' instrumental and parts, 1 was bought by a local party.


texts: Why does spoiler extension during touchdown cause a pitch up moment?

texts:
There are reports that incorrect flight technique associated with spoilers extension during touchdown were contributing factors to pitch increase after landing, causing tail strikes in jet transport aircraft.
Why does the spoiler extension causes a pitch up moment in the aircraft after touchdown?


texts: How heavy are the Boeing 747 landing gear?

texts:
Does anyone know how heavy are the combined landing gear on a Boeing 747?

It would be interesting if someone has also weight statistics per gear (nose gear and the four other main gear).


texts: Would a random passenger be allowed to fix a problem with a commercial aircraft?

texts:
I just read an article about a man (who is alledgedly an airplane mechanic) who was a passenger on an airplane that had some mechanical issues. Because there were no 'local' mechanics around, he decided to take matters into his own hands and fix the problem himself.

Here's the article I read (it's in Dutch though)

Here's one in English

This all seems nice but in this day of age where airplane security and regulation is so tight, I wonder if this is possible at all. It also seems to me that by the airplane company is taking a huge risk in letting this "random" person fix this problem. The article obviously oversimplifies a few things, but regardless of that, here's my question:

Is it possible for a random passenger, who also happens to be an airplane mechanic (working for airline X) to fix an issue on the airplane he happens to be on, given that there are no "local" mechanics around (however unlikely that might be)?


texts: What is the Function of Pressurization Light on Exit Doors for Commercial Airliners?

texts: I am well aware that the average human is unable to open plug doors in flight due to pressurization of the cabin. I've noticed, however, a "cabin pressure" warning light in the window of exit doors, and specific instructions to not try to open the door when the light is on. Is there an actual danger of someone outside the aircraft being able to release something in or around the door while the cabin is under pressure, or is the light simply to indicate why they would be unable to move the handle?


texts: What are the units for the bearing to center of an airport from radio aids to navigation in chart supplement?

texts: Is the bearing to the center of airport for a radio aid to navigation in the chart supplement, true course, magnetic course, is it based on the VOR's radials, or is it something else?


texts: Has the FAA ever granted anybody a license honoris causa?

texts: Say, anybody who made an outstanding contribution to technology, flight methodologies, etc (for example, the Wright Brothers); has the FAA ever issued a license (private pilot, etc.) to anyone that deserved such honor?


texts: Why are fuel tanks in the wings filled first, and why are they used last?

texts:
When fueling airliners, why is fuel filled first in the tanks in the wings and then the center tanks? And why do they use fuel from the center tanks first and then from the tanks in the wings?

From my research I've found the purpose is not to give too much stress to the structure of the wings, but I don't understand exactly how it works. How does having fuel first in the wings and leaving it last in the wings help protect the structure of the wings?


texts: How much lift do planes produce before rotation?

texts: In the takeoff roll, I'm pretty sure planes produce some lift before rotation, but how much? Is it insignificant compared to post-rotation, or is it large compared to the post-rotation lift?


texts: Which fighter jet is the safest outside of combat?

texts: I've heard that the Bloodhound SSC project decided to use a Eurofighter engine, because this was "safe". This got me wondering if there are any numbers on which fighter jets are safest. Something like a non-combat fatalities to flight hours ratio?


texts: Does the altitude or attitude of an aircraft affect GPS accuracy?

texts:
Of course we are assuming an effective signal is being received.

I live near Idaho Falls, Idaho with a field elev of 5300ft. If I shoot an approach will GPS be more or less accurate then landing at Seattle or LA?

Does the accuracy of GPS change with aircraft altitude or attitude?


texts:
Where does the final approach segment begin on an ILS approach? It may not be as simple as it sounds to answer. The reason I ask is because I've found some support for at least two answers.

One is that final begins when passing the glide slope intercept point a the last no lower than altitude for the approach. This is the point denoted by the lightning bolt arrow on government charts.

Another answer I've heard is that it begins when glide slope has be intercepted within the limitations of the glide slope and on an approach segment. For the example plate above, this would mean that if the glide slope were intercepted between SILKY and JAKOR the pilot would be considered to be past the final approach fix for all intents and purposes and might even configure the airplane for landing at that point rather than passing JAKOR at the published glide slope intercept.

I think there are valid arguments for both, but I'd apprecate more insight and references on the topic.


texts: How miraculous was the miracle on the Hudson?

texts:
The "miracle on the Hudson" was extremely unusual - dual engine failures and successful off-field landings in commercial A320-size aircraft are very rare. The event has been dramatized and the crew (and captain "Sully" in particular) have been widely praised as heroes.

The crew certainly did an excellent job ensuring that all those aboard lived to tell the tale. But was it really exceptional? Aren't all commercial pilots trained to handle emergencies? I don't want to belittle the fantastic job the crew did, but I wonder whether they did something no other crew could do or whether this is something most crew would be able to handle if called upon.

Here is a more precise question:

If a random commercial airline crew were placed in the same situation as the crew of US Airways Flight 1549 on 15 January 2009, how likely is it that they would achieve an outcome with no fatalities?

I understand that to a certain extent this is a matter of opinion, but I hope people can provide some objective comments about what situations crews are trained for and whether there are other comparable examples with similar or differing outcomes.


texts: Are there different symbols or graphics to identify different types of GA fuels?

texts: Are there different symbols to identify the different types of fuels used for general aviation aircraft?


texts: How are special flight paths coordinated with ATC?

texts:
I assume they have to enter a flightplan for this or do say just say "it's a test, please clear airspace for us around the complete US"?

Still flying and completing the right wing.

I would appreciate it with a 747-8, harder to draw :)


texts: Does a hold-entry count as a hold for instrument currency?

texts:
So in looking at the instrument currency requirements for the FAA (6 approaches, holds, intercepting & tracking courses), I'm having difficulty nailing down what constitutes a hold.
Based on AIM 5-4-9(a)(5) where it talks about HILPT, it sounds like all I need is to do the hold-entry and get established inbound, which feels a bit odd since for a parallel-entry since that's nearly equivalent to a procedure turn (which I believe wouldn't count as a hold).

The holding pattern maneuver is completed when the aircraft is established on the inbound course after executing the appropriate entry.

Based on the above, I assume if I fly a HILPT as part of an approach in actual/simulated instrument conditions, I can count that as a hold. Following that logic, would flying the hold-entry at a missed approach fix also qualify as flying a hold? Or does that excerpt above only apply to a HILPT?
Is there any official guidance/interpretation provided in regards to this?


texts: What is the difference between a Mechanic and a Repairman?

texts: In reviewing some of the data published by the FAA, I noticed that they make a distinction between a mechanic certificate and a repairman certificate.  What is the difference?


texts: How can I convert a Georgian CPL to an EASA frozen ATPL?

texts: I am interested in how I can convert my CPL issued by Georgia to a frozen ATPL? Georgia is not a member of EASA.


texts: What is the overhead instrument panel (pictured) near the front galley area of an A320?

texts:
I have noticed this overhead instrument panel. It is convered by a transparent plastic lid with a small hole in the middle. Inside it has lot of switches. What is it supposed to do and who operates the same?

I couldn't find an exact picture, but the below image highlights the area where the panel is:

Image Source


texts: Why was the WWII RAF fighter joy stick loop design not used widely?

texts: WWII RAF fighters had a loop on top of the joy stick in case of hand loss or injury - Anyone know why the Allies didn't copy this very helpful idea?


texts: With current technology, why is there still increased separation between aircraft and delays in low visibility conditions?

texts: Since most (if not all) commercial aircraft are equipped with inertial and satellite/GPS navigation, why is increased separation between aircraft necessary? Can't controllers immediately identify the position and velocity of every aircraft?


texts: What is the weight of ballistic recovery systems?

texts: How much does a Ballistic Recovery Systems parachute system weigh?  I wouldn't want to use a personal quadcopter or jetpack without one.  I wonder if they could be made small and light enough for a small JB-9 type jetpack.


texts:
What is exemption 17347 in the context of dispatch for FAA domestic carriers?

The explanation can be rather complicated, so I’m looking for a simple and straight forward break down.

Also, as a bonus, what is the history behind this exemption?


texts: Is there a minimum weight requirement for flying manned aircraft in controlled airspace (B, C, D, E)?

texts:
The Colomban Cri-Cri is a small twin engine plane with an empty weight of ~200 lbs and a MTOW of ~400 lbs.

Can I fly this in controlled airspace? What are the requirements for aircraft registration?


texts: Is there any way to stop a pilot from crashing an airliner?

texts:
If a pilot decides to crash an airliner, a la Germanwings or Egyptair, could he be stopped?

In those cases the offending pilot waited until he was alone in the cockpit to act. Thus many airlines have made it mandatory for there to be two crew members in the cockpit at all times, even if it's just a flight attendant to stand in there and wait for a pilot to return.

Although that might give passengers some piece of mind I am doubting that it would do much good. It seems to me that, even if the other pilot is in his seat and strapped in, if a pilot decides to crash the plane he could kill the engines and put the plane in an unrecoverable attitude very quickly.

Is this a correct assumption? Would Airbus envelope protections prevent this? Can the plane be placed in direct mode to override the protections?  What about a 777? Does the yoke feedback system allow one pilot to overpower the other?  The engines could easily be throttled back, but could they be quickly shut down requiring a restart? What could the other pilot do to stop his actions?


texts: How does the Boeing 787 Dreamliner's glide ratio compare to other airliners?

texts:
I just saw a documentary on the design of the Boeing 787 "Dreamliner" and one of the designers said that the wings were inspired by gliders. Looking at the production version of the plane, it is obvious that the wings are indeed more glider-like than other airliners.

How does that affect the glide ratio? I can't find any data on this (is there any data on that at all?)


texts: Does mid-air refueling have very hard constraints on weather?

texts:
I'm guessing mid-air refueling has constraints on windspeed and wind direction, visibility, and precipitation. I may have missed some, but those alone make me feel like mid-air refueling can't be done most of the time (?)

About wind direction though, I guess you could just fly in the "right direction", but then this would also have constraints because the "right" direction could lead away from your ultimate destination.

(also, is there a mid-air refueling tag I couldn't find?)


texts: Why couldn't the DHL611 crew hear the ATC transmissions for the Bashkirian 2937 crew?

texts: In the mid-air collision over Uberlingen, why couldn't the DHL611 crew hear the instructions given by the controller to Bashkirian 2937 crew if both aircraft were on the same frequency?


texts: What are the measurements for a "Black Box"?

texts: I was wondering as to the measurements of  "black box" recorders. I have a new invention involving the "Black Box" and I need to know the measurements of the recorder.


texts: Why is the L/D ratio numerically equal to the glide ratio?

texts:
*L/D is ratio of two forces, lift and drag.
*Glide ratio is ratio of two distances.
Can you explain mathematically how they end up  numerically equal and are they always equal?


texts: What were the rules for logging "simulator" instrument time in 1994 (non-full motion)?

texts:
Long before the FAA updated the rules of BATD, AATD, FFS, and FTD, what were the rules for logging simulated instrument time in a synthetic trainer?
Specifically, this question came up, an older pilot had a few log book entries for simulated instrument in a Curtiss-Wright P.3 simulator and it was logged as "simulated instrument", "synthetic trainer" and "total flight time." Nowadays, you do NOT log instrument time in a simulator (unless its full motion) as "total fight time", but how was it logged back in 1994? This person's log book entries were logged by an instructor/simulator operator, and the entry was signed off by the instructor. I looked it up and the Curtiss-Wright P.3 was used by airlines to do instrument training, but I couldn't find anything on how that time was appropriately logged back in 1994.
I imagine back then it may have been appropriate to log it as flight time, but I can't find anything that old that says anything one way or the other.
UPDATE: I found AC 120-45A issued in 1992, which described Airplane Flight Training Device Qualifications. Section 14 of this AC said that Previously Approved Flight Training Devices are essentially grandfathered for 5 years from the date of that AC in 1992. So if the Curtis-Wright P.3 was previously approved as a flight training device then, it would be grandfathered. So, if anyone knows if the Curits-Wright P.3 was ever approved as a flight training devices, that would be helpful as well.


texts: Is any single-axis autopilot for a light piston single certified for unusual-attitude recovery?

texts: Recovery from unusual attitudes is required during primary training and must be demonstrated during the checkride. In the case of an incapacitated or disoriented pilot, will activating a single-axis autopilot in ROL mode while in an unusual attitude safely recover straight-and-level flight?


texts:
I am writing an essay on how a jet engine works, so I need specific answers on this.

What percent of the air that is sucked into the engine is bypass air? I have heard that bypass air provides about 60% of the thrust.  How does cold air provide thrust?  I was under the impression that hot air makes much more thrust than cold.


texts: How does an A330 detect stall without airspeed?

texts:
On Air France 447 the crew had experienced complete failure of the pitot static system, which meant they lost their readings on their airspeed indicators, but according to the Mayday / Air Crash Investigations episode the aircraft had detected that the plane was about to enter an aerodynamic stall and the stall warning systems were activated just before the crash.

How did the A330 in question detect that the plane was on the verge of stalling without the airspeed indicators working?


texts: What is the purpose of the glazed round area atop the Ju 87 Stuka G?

texts:
I haven't been able to find any pictures of this feature aside from models, nor any reference to what it is.

I'm going to make a complete guess and suggest it's a searchlight for night-fighting to illuminate the underside of bombers.

Italeri Ju 87 G-2

Hobby Craft Ju 87 G-1

Hasegawa Ju 87 G-1


texts: Why angle of attack is always shown against the relative wind parallel to horizon?

texts:
I have a question about Stall, which I have difficulty to understand.
According to the theory, stall happens when :
1-  Speed is slow then a certain limit.
2-  Angle of attack is greater than a certain limit.
In the case of angle of attack, there is being spoken about relative wind along the wings.
But here is my confusion.
Relative wind is always shown parallel to the horizon, which strikes the wings.
While in my understanding, in the sky there is equal air and wind everywhere. We create our own hard wind for our wings, by moving fast through the air. Right?
So it should not make any difference in which direction we move, along the horizon, or at a steep angle upwards or downwards, relative to the horizon. The relative hard wind will be created straight in opposite direction where we move fast. Because we are also moving in the same direction as our wings angle of attack.
As I have shown with blue line in my illustration above.
If so, then there is no question about angle of attack at all. Because we always create our own wind by moving fast in any direction in the sky.
It would be different if we are moving parallel to the horizon, but only our wings have a greater angle of attack relative to the fuselage and the horizon. (As it is often explained in the example of, hand out of a car. While car is moving horizontally, but only the angle of our hand changes relative to the car). Then this stall theory is understandable.
If we look at the fighter jets and acrobatic airplanes, then we see that they can climb vertically up against the horizon, at 90 degree bank angle and fly upside down too. And they do no stall, because they create their own relative straight opposite wind by moving fast in any direction in the sky.
So why in normal planes we do have to think about straight only horizontally coming relative wind and accordingly the angle of attack against it?


texts: Why do you have to put the blinds up during take off and landing?

texts: I understand the rationale for putting seat backs straight, folding tables, fastening seatbelts etc., but I've never really understood why the window blinds matter.


texts: Why do tapered wings not stall at the root first?

texts: Why do moderate tapered wings stall first at mid-wing section and high tapered wings stall at tip first? The effective AoA should be always higher close to the root? (considering no geometric or aerodynamic washout)


texts:
Below is a picture of the Junkers F.13.

What does the letter D on the underside of the wing stand for?

(Image Source)


texts: When we say that a missile has been locked on a target (lets assume a fast moving target, and that the missile is mounted on a fast moving plane), we assume that once the missile has been locked onto the target, it will actually hit the target after firing (Irrespective of the subsequent changes in the position, velocity and acceleration of the target). How does this system work?


texts: Why does a turbofan engine force bypass air into a smaller space?

texts:
I asked a question about this same concept recently but this question involves the function of the bypass air.

In this YouTube video around 1 minute in the narrator says that the bypass air is pushed by the fan into a smaller and smaller space which increases the velocity of it, but why? Why increase the exit velocity of the air beyond what the fan already does? It can't increase thrust, can it? That would seem to violate some sort of conservation law since you could theorize an infinitely narrowing space and thrust would approach infinity. So what function does it actually serve to force air into an 'ever narrowing space'?


texts:
How are V speeds spoken? --Research for my novel.

Is it the V and the number or letter notation or is there something more to it?

The Wikipedia Page on V Speeds does not delve into the subject matter.  I did search the search box, prior to submitting, but nothing has come up.

Please don't get angry by my question or restrict my learning.  I can always go to a better source--I got a message some of my past questions were not well received.


texts: Why did the backup landing gear deployment fail on LOT 16?

texts:
LOT 16 was a 767 which experienced a hydraulic leak, resulting in the failure of the landing gears and the proceeding belly landing shown below:

Why did the backup system(s) fail? I was under the impression that a gravity/freefall backup is mandatory.


texts: Is there a commonly recognized placeholder airline name?

texts:
I'm wondering if there is a common placeholder name for an airline, either implying a legally disclosed or fictional entity, which is frequently used?

For instance, I've seen the terms containing 'widgets' used very often in an economics context. John Doe is often used in legal cases.

*"Placeholder names are words that can refer to objects or people whose names are temporarily forgotten, irrelevant, or unknown in the context in which they are being discussed." -Wikipedia


texts: What is the range of pressures a space shuttle can withstand?

texts:
Pressures, as on the external surface of the space shuttle. I want to design my own functioning space shuttle (on an extremely fundamental level with consideration of only the external structure, nowhere close to the real thing) and would like to run a wind tunnel test on it, and I wanted to know what pressures a space shuttle can withstand in order to design my own spacecraft to match and potentially exceed those values.
I appreciate any help that anybody can give me, even if it happens to be some advice, constructive criticism, or the answer to my question.


texts:
I kind of know what it is but I don't fully understand it. Wikipedia says,

  the engine pressure ratio (EPR) is the total pressure ratio across a jet engine, measured as the ratio of the total pressure at the exit of the propelling nozzle divided by the total pressure at the entry to the compressor.

I know where the entry of the compressor and exit of the propelling nozzle but I don't get what they mean by pressure. Do they mean air pressure?


texts: Why is the wrong explanation of "air travels a longer distance and creates a lift" so popular?

texts:
When I was learning for my license, one of the first diagrams I remember was about the wing profile. The air going around the wing and on the upper side it has to travel a longer way, thus generating lower pressure and bang, plane is flying.
Same explanation already back at school.

See my other question: if the theory was right, why can planes fly inverted?

So here's the follow up: why is this wrong theory so popular and still part of books?

Wouldn't it make sense to teach students how a wing really works? I mean just look at any RC plane meeting - you'll be amazed what weird designs are capable of flying if there's enough engine power.


texts: Airline safety: what happened between 1959 and 1962?

texts:
The graph on page 17 (PDF page 18) of this Boeing air safety publication shows the fatal accident rate for commercial jets in the US and Canada dropped from about 40 per million departures in 1959 to 2 per million departures in 1962.  Since then, the rate has declined even further, but nothing as dramatic as the original drop.

What happened during the the 1959-1962 period to so greatly reduce the accident rate?


texts: Is MIL-STD-1553 still used in modern aircraft?

texts:
I am working on an assignment for my "Avionics Systems Design" class and I want to use MIL-STD-1553 for my aircraft system. But according to some shady blogs this STD has been deprecated or superseded by MIL-STD-1773.
If I don't want to use an optical solution, what is the best bus for my system?


texts: How can I calculate the maximum range of an aircraft descending with power (not gliding)?

texts:
Let's assume I have an aircraft, for which the thrust is not enough to keep the altitude. So over time I will lose some altitude. But it will still go further then it would without having an engine (gliding).

How can I calculate the maximum possible range for this case?

I know the Breguet equation, but I do not think this helps me in this case?

Some formulas would be great.


texts: Will a stalled aircraft fall down like a brick? Or how steep does the Lift-AoA curve fall off after stall?

texts:
When an aircraft stalls, do all or most lift forces abruptly disappear or is this transition continuous?
Will the aircraft drop from the sky like a brick or can this (losing lift and altitude) happen so gradually that it will be entirely unnoticed from the crew and passengers?

I'm troubled by this sentence on Wikipedia referring to the AF447 disaster:
"The aircraft remained stalled during its entire 3 minute 30 second descent from 38,000 feet (12,000 m)"
(source: https://en.wikipedia.org/wiki/Air_France_Flight_447#Accident)
It seems the crew were unaware of the stall condition. (But let's not discuss the reasons here)

If lift abruptly disappears when entering a stall, wouldn't people notice a considerable loss in perceived body weight at least as long the aircraft accelerates downward and builds up vertical speed downward.
I expect that the airframe experiences enormous drag in the vertical direction once downward speed is being built up and it probably reaches an equilibrium condition limiting its fall rate.

But if lift disappears abruptly during the stall, then you should have a sensation of free fall (no weight) at least during a short time.
Is this the case or does lift diminish continiously during a stall?

PS: While writing the question i have searched and found those Lift-AoA diagrams (like this: https://www.grc.nasa.gov/www/k-12/airplane/incline.html) that should be able to answer the question.
Basically my question is: How quickly does Lift drop off to the right of the diagram. All diagrams i found did not in fact go much beyond the stall condition.


texts: Is there a way for an ultralight or powered glider to smoothly enter a jet stream?

texts: Once inside the jet stream altitude 7-15 km is it all that turbulent or is there a way to enter it smoothly for an ultralight plane or a powered glider? More info


texts: Can I leave my smartphone turned on in the checked-in luggage?

texts: For obvious reasons, that's the best way of tracking the whereabouts of my luggage. Once the plane lands, it would establish a 3G connection, and I would be able to access its GPS position.


texts: Is there any way to determine or estimate where the cloud tops are?

texts:
There are various ways to find out or at least estimate where cloud bases are, e.g. ATIS/AWOS/ASOS report them directly, PIREPs may mention them, and you can make a rough estimate based on the temperature/dew point spread.

Is there any way to determine (or estimate) where the tops are, assuming that no PIREPs are available?


texts: Which Velocity is used to measure Dynamic Pressure?

texts: Suppose an airplane is flying in windy conditions. Now, for the calculation of the dynamic pressure should I use the relative velocity or the absolute velocity as the free stream airspeed?


texts: What does it mean when your destination airport is currently "below IFR minimums"?

texts: Does it mean that absolutely nobody can land there until conditions improve? Can ATC still give you an IFR clearance to your destination airport in this case?


texts: Why should you not turn in the direction of an inoperative engine?

texts:
In two-engine aircraft with wing-mounted engines when one engine quits the aircraft will have a natural tendency to turn to the dead engine. So if you need to turn, it seems logical it should be easier to turn that way.

However in the discussion here is a comment:

  By dinger on Monday, Aug 11th 2014 13:42Z:
  SOP in a twin is NOT to turn in the direction of the failed engine. Right engine failed and they turned Right.

Is it really standard procedure, and if it is, what is the reason behind it?


texts: Who logs the flight hours for airline pilots?

texts: Airline pilots' flight hours vary a lot depending on the airline, type of operation etc. Who actually does the job of logging their flight hours? Do the pilots do that themselves after each flight or there is a system that does it for them?


texts: Who decides an aircraft's maintenance schedule?

texts:
I've found a 737 maintenance planning data document produced by Boeing, which gives a suggested schedule on page 6.

I've also found a British Airways Fact Book document, which on the last page gives a schedule.

So who decides how often an aircraft and its individual components should be inspected? Is it the manufacturer, the airline, or somebody else? Is there a set standard or does this differ between manufacturers/airlines/countries?


texts: Why did Britain develop three different bombers (V-bombers) after WW2 instead of one?

texts:
Why did Great Britain develop three different planes - Victor, Valiant and Vulcan - after WW2 for the same task?

I suppose that at that time the US and the Soviet Union were producing high numbers of bombers too, but did those countries stick to one design? Why did France not produce different bombers? My main question is about the effort of Great Britain and I am listing other countries only as examples.

Here is the Handley Page Victor:
(source)

Here is the Vickers Valiant:
(source)

and the Avro Vulcan:
(source)


texts: What is the difference between a stall fence and a vortex generator?

texts: Both of them prevent the aircraft from stalling, so is there any difference between them? The wing fence doesn't produce a vortex, so how does it work?


texts: What does the Boeing 777 autopilot do after reaching the last programmed waypoint?

texts:
As I understand it, a series of waypoints can be programmed, by a pilot, into one of the autopilots on a Boeing 777. If the autopilot is engaged, the autopilot will cause the aircraft to fly to each waypoint in turn, automatically steering the aircraft as necessary.

It is not clear to me whether the autopilot automatically disengages after reaching the final waypoint or whether it maintains (for example) a magnetic heading and altitude.

What happens after reaching the last programmed waypoint if the pilot does not intervene?


texts: How was the navigation managed on jetliners before having programmable routes?

texts:
This in-flight photo provides a look into the pre-FMS era (also pre-INS), i.e., not having a programmable route.

How was the navigation managed back then? (Question limited to 2-crew jetliners, or jetliners that lacked a navigator position.)

What I'm interested in the division of crew duties, methodology of switching to stations (given the high ground speed of jet-liners), the expected/required accuracy, the use of reminders if any, etc. Basically, how it was managed.

I'm not asking how to navigate using VOR, NDB, etc., only the operational aspect.

Dissecting the photo above:

Lack of FMS.
Autopilot flying a heading select (heading 172, most probably not ATC issued) in cruise (PERF CRZ).
Laid-back accuracy (not a bad thing).

For example, a VOR/LOC mode was available but wasn't used.

NAV 1 radio selector.
NAV 2 radio selector (opposite side).
That's not an FMS, that's a PMS (Performance Management System) for flying the optimum vertical profile.


texts: Does a standalone EASA Multi-Engine Instrument Rating exist?

texts: I'm starting an A320 type rating in a couple of months, but my MEP/IR is expiring before that. The pre-entry requirements were only a ME IR. Got me wondering: can I just revalidate my ME IR and let my MEP expire? In other words: is there such a thing as a standalone ME IR (meaning no class or type rating that goes with it)? Thanks and happy landings!


texts: What's the purpose of depiction of visual flight track on some Jeppesen approach charts?

texts: 29 is the visual flight track in this chart. Why is it depicted from the MAP to the threshold of the runway? Does it signify some alternative procedures pilots are expected to perform if they decide not to perform a missed approach at the MAP?


texts: How beneficial are flaps when landing with a tailwind?

texts:
I understand that flaps are devices used to increase the amount of lift and drag. When landing with a tailwind your groundspeed will be higher. Therefore, flaps would help reduce this groundspeed, logically allowing for a lower touchdown speed.

Should flaps always be applied with a tailwind? Are there reasons not to use flaps when landing with a tailwind?


texts: Low hour Pilot wants to move up to Piper Malibu Mirage but having trouble finding insurance

texts:
I am a 350 hour instrument rated pilot and current. I own and fly a Piper Saratoga II TC and I am rated for complex, high performance, retractable wheel airplanes. I have approximately 150 hours in the PA 32. Current age 59.
I want to move up to a FIKI factory installed airplane and have been mentored that perhaps the PA 46 Piper Malibu Mirage would be a great next step.
Having issues with companies willing to insure me even though my Saratoga has similar systems just not quite as fast. Any suggestions from anyone on what I can do except fly more hours to get insurance?


texts: Why is a Cessna C560 circling Washington DC during the protests?

texts:
Right now according to FlightRadar24 there is a Cessna C560 circling Washington DC.

It took off from Manassas Regional Airport and has been circling ever since. No other identification is listed.

Is there any other way to find out what this plane is doing and why it would be flying now?


texts: How can opening of a door on small plane cause a drop in altitude?

texts: Last week in Ecuador I was on a flight in a small plane (twin engine prop, full with pilot and 5 passengers). The passenger door opened in flight. I was in a position to grab the door and pull it back to the plane and hold it (against a very strong pull) until I could slam it partially shut and then hold it in place until we landed. It didn't seem like that big of a deal except when the door first flew open the plane seemed to drop about 50 feet. What caused the drop in altitude?


texts: Is it feasible to replace brakes on airplanes with electric motor/generator?

texts:
Would it be feasible to replace the brakes on airplanes with electric motor/generator drive systems?

There are two problems I see with airplanes. When they land, the tires are not spinning to match the ground speed, as the craft touches the ground. So there is a sudden lurch as the tires touch the ground and suddenly begin spinning. The bigger the craft, the more tire mass that must be instantly accelerated.

This disrupts flight stability, and the jolt could be enough to cause a crash or mishap in poor landing conditions. It also causes unnecessary wear and stress to the tires due to the motionless rubber dragging across the runway pavement at first contact.

It would be best for the tires to be spun up to match the ground speed before the craft touches the ground, for the smoothest landing possible.

The second part is just simply the problem of dissipation of heat. It has been discussed elsewhere here that the heat from braking can cause fires and crashes.

As in train locomotives, with a braking motor/generator, the heat could potentially be moved elsewhere to resistive heat coils covering a large area, and cooled using forward thrust or fans.

With a motor/generator unit, the tires can be spun up to either near or matching ground speed, using them as motors powered by the APU, and then switched to be used as generators for braking after ground contact is made.

Has this ever been researched or used on airplanes?

(As a lower middle-class American that is not involved in the airplane industry, I have no hope of doing anything with this or profiting from it, even if it is a practical and potentially patentable new concept that has never been tried before.)

EDIT

I am not talking about regenerative braking or energy recovery into a storage battery. Someone has inferred that though I didn't say anything about it at all.

I understand the storage battery would likely be too much extra weight for a plane to carry, vs the energy recovery of takeoff and landing. (Heh, have a 2000 ft breakaway extension cord on a reel, to drive it down the runway and disconnect right before it lifts off the ground.)

I am only looking at resistive / dynamic braking, dumping the heat in huge resistor banks with a high speed blower, the same as is used on train locomotives. On a plane, air bleed from the engines can blow across the the resistor banks.
Probably should pluralize the title. Rather than a single huge motor/generator, each brake assembly would be replaced by a separate one of these.

So a large plane with say 20 wheels would have 20 motor/generator units, these running at high voltage to keep the amps and wire diameter small. This reduces weight and engineering complexity, eliminating gears and shafts linking all wheels on one set of gear, to one huge motor/gen unit.
This is not two separate devices, but one device that does both functions. Most (but not all) generic electric motors without electronic drive systems can also be a generator.

This could use a permanent magnet motor, or with a powered field coil. Neodymium is capable of extremely high flux density, but loses it when exposed to high heat, so there are density / temperature tradeoffs of permanent vs powered field coils.
Tire hub could potentially be integrated as part of the motor/gen rotor/casing for weight savings (which is very important in aircraft), using a fixed core and a hub that rotates around it in reverse of conventional motor design.


texts: Do autopilots have an 'activate' switch/button, in addition to 'on' and 'off'?

texts: Say cruising at FL310 and on a 270 heading with autopilot on. If pilot decides to descend to say, FL180 on a 180 heading, is simply changing the altitude and heading numbers on the autopilot control panel enough for the autopilot to get going with the new commands, or after changing the altitude and heading request, there is some sort of button that commands the autopilot to execute the new commands? And if so, where is that switch (or button) and what is it called?


texts: Does runway center lighting increase runway lifetime?

texts:
I wonder if the centerline lighting helps add a few more years to the runway, especially with heavy aircraft like A350/A380, in addition of being helpful for landing and takeoff?

My question is based on a recent reading where this question was asked:

  Why did the airport operator BIAL not plan for centre line lighting
  at the time of runway construction?

Update - From what little I garnered, understood and logic applied, it seems/feels that a centre line lightning would make when the airplane lands with more precision than otherwise. This would mean that the aircraft doesn't go all over the place and while some specific parts of the runaway would be more stressed, others wouldn't. I know there are a mixture of narrow and wide-body aircraft but still it should make life of the runaway, at least on the edges more. Also maintenance of the runaway should be a tad easier as perhaps only some specific parts of the runaway would need more maintenance . I may be totally off in my assessment hence asking here.

Update 2 - From the comments then, what is the centreline lightning useful for ? Also if there any pictures which explains it as well would be useful. I know there are lights on left and right of the aircraft for it to know that there is a runaway here. What does centreline lightning bring to the table ?


texts: For a plane with a pusher propeller, how does a root-stalled wing affect its performance?

texts:
My understanding is that it is desirable for the inboard part of the wing to stall first to maintain aileron effectiveness.

For the configuration shown below, if the inboard part of the wing stalls first, what would the effect be on the propeller performance? Is there an equation that estimates the effects?

Source: https://en.wikipedia.org/wiki/IAI_Heron