texts: What is "judgemental oversteering" in taxi procedures?

texts:
I found a phrase that I don't understand while reading Jeppesen charts: "judgemental oversteering".

I found it in general information about taxi procedures. As I understand this procedure applies only to jumbo aircraft because it takes place only if the wingspan is more than 118ft (according to the chart which I read).

Can you explain to me what is it? What kind of conditions can require this procedure? Examples or images would be appreciated.


texts: How can I continue my flying career in the USA?

texts:
I'd like some guidance for my career. I completed my basic CPL from South Africa in 2009 and got a job in January 2015 flying a C208B in Nepal. Now I'm in the USA for more than a year and I'm thinking about continuing my flying here. I have less than 300 hours.

So what do I do now? What is the process to convert my license to an FAA one? What would be a good flying school to join in New York?


texts: Is it normal procedure to lower flaps at high altitudes?

texts: I was flying on a Boeing 747-800 today and the pilot opened up flaps at high altitude. This caused sharp descend for about 5 seconds ( Causing slight panic onboard ) , the pilot leveled the flaps again after about a minute and the aircraft became much smoother. Is it normal to use flaps like these or this might be an error?


texts: Why is it not allowed to dispatch an Airbus A320 with an inoperative ELAC 2?

texts: In the case of ELAC 2 failure, ELAC 1 will take over. However, it is not allowed to dispatch an Airbus A320 with an inoperative ELAC 2. Why is that?


texts:
How to calculate the minimum radius of a turn at high alpha, without banking?

One sees the radio control guys flying their planes at 30deg AOA in a 5' circle at walking speed, without banking.

Obviously 99% of GA planes can't fly that slow, but what radius can one fly at slow speeds, , say at 20 deg AOA, 10 mph above stall, say 50mph in something like a Cessna150.......without banking?


texts: How does a DC-10 flight engineer manually raise the cabin altitude?

texts: Reading into Federal Express Flight 1406 and I noticed when the flight engineer said he was raising the cabin altitude “manually” I assume this has something to do with cutting off the oxygen, but how can it be done manually? This also makes me curious to know if there is another way of doing it, but would be disabled under certain emergency scenarios?


texts: Is there a way to design intake duct and nozzle in Ansys AFD or other computational softwares?

texts: I designed the fan for an electric propulsion system and am trying to design the intake duct and nozzle to that fan. I used AFD Ansys to design the fan and I searched if there was a way to use AFD to design the intake duct and nozzle but not really found anything. I'm wondering whether there is a way to design the intake duct and nozzle using computational software in a similar method to using AFD Ansys for the fan because I would like to be able to CFD analysis on it, or whether it's just case where I should design the geometry of the intake duct and nozzle on AutoCAD and use that geometry to generate a mesh for CFD analysis on Ansys


texts: Since a V-tail is lighter and generates less drag than a conventional empennage, why has this solution been put away from production?


texts: Has there ever been a centrifugal turbine in an aircraft engine?

texts:
These days, most jet engines feature axial compressors and turbines. However, there are some older aircraft engines with centrifugal compressors, like the Rolls Royce Nene. But I've never heard of any engine with a centrifugal turbine (radial flow turbine).
Does such a thing exist? Has one ever been built, tested, and flown? I'm interested in turboprops, turbojets, turbofans, even very tiny ones for RC aircraft.
Edit: Okay a radial flow turbine will not produce much of a jet of thrust, so I guess the only possible engine for this would be a turboprop. Edit 2: Not necessarily, a centrifugal compressor can redirect air outwards to another path, then downwards into a centrifugal turbine, which redirects it back to axial direction after all.


texts: White light illuminating the engine coming on at intervals in flight; Curious what's the protocol?

texts:
I was recently flying Air China from Beijing to Bombay & happened to seat on the Window seat close to the wings.

I could see the engines and there was a light that could illuminate the engines. As I recall it was switched on at some point at the end of taxi and pre takeoff but I don't remember exactly.

What I do remember is that at some points during flight I saw the engine illuminated by this light and at other points (pretty much most of the flight duration) the light was off.

Just curious what the protocol was.

The aircraft type seems to be Airbus A330-300.

https://uk.flightaware.com/live/flight/CCA889

This was a neutral color steady light and not one of the red / blue ones nor the strobe. From the color it looked more like LED illumination.

PS. From the related question on SE Aviation the responsible light seems to be what they call a "Wing light". But my question is different than that one because why would the flight crew turn on the wing light during cruise altitude flight periodically?

There was no crew in the cabin for a damage / ice inspection (I've seen them use wing lights for this purpose post a deicing spray but then the flight crew comes into the cabin to look )


texts: How do I locate a list of restrictions that would prevent a pilot from flying in the US?

texts:
I have a privacy preserving technology that could conceivably help prevent the Germanwings crash of 2014.  The idea would be there is a long list of issues that would prohibit a pilot from flying encoded on a ID card that anonymizes a pilot's information:

I'm guessing that a list might look like this:

Overwork (no sleep)
Simulator experience, test results
Medical issues (temporary)
Drug tests
Psychological issues

A list of medical providers would link the results together, anonymously, and during the pre-flight check, the ID card would be scanned and rather than a specific issue being highlighted, (depression), the pilot would be asked to rest for a while.  No system would know why the rejection occurred, except for the pilot himself.

This might for a balance of privacy, safety, and accountability without compromising need to know.

That being said, I would appreciate any official, or carrier specific list of reasons a pilot would be rejected from flying.  The closest I've gotten to learning about this is MSFT Flight Simulator and a few hours in a Cessna

Supplemental information would be helpful as well (your thoughts about this solution)

Scope

Per the comments below this question, the scope is limited to US


texts: Would airline got charge for late on depart from the gate due to passenger boarding issue? If so, what is the charge like?

texts:
Airline wants the boarding be completed as quick as possible.  I wonder what is the cost for any delay? On the other hand, I want get a dollar value for any delay and see the justification value for any improvement.  So, I wonder airline would get additional charge for the gate on delay ?
Thanks.


texts:
What information about own aircraft does TCAS Mode s( all call) send in the interrogation?
What information does Mode S transponder(intruder)replay to TCAS interrogation?


texts: Is a "T" (Tango) prefix required before the registration number for Part 135 flights?

texts:
After September 11th, the FAA required all Part 135 air carrier flights to prefix their registration number with a "T" and use the "Tango November" prefix on the radio.

Every once in a great while (about once to twice a year) I still hear someone doing this, but surely there are more 135 flights than this.

Is it (or was it ever) required to use the "T" prefix for Part 135 flights?


texts: What is the Scaling Factor in ARINC 429?

texts:
I'm a newly appointed engineer in an avionics company and have been tasked with preparing a report on ARINC429. I understand most of it, and I certainly find it simpler that 664, but I still can't manage to wrap my head around what "Scaling Factor" is.
No resource on ARINC429 I have found goes into detail about this, and the best I could find is image below.

This is a screenshot from a link discussing the standard.

Could anyone please explain what this is trying to convey?


texts: What are the limiting factors when flying a model UAV plane to high altitude?

texts:
Setting aside the likely legal factors for a moment, what are the limiting factors when flying a model plane to high altitude?

As I see it these could be:

Battery power consumption - Model planes seem to have a battery life of less than an hour. There is a large distance to be covered in a climb ~20KM.
External forces - Strong winds/turbulence acting on a relatively small and light airframe could easily blow the plane off course. I'm not sure how severe these would be at higher altitude.
Air pressure/oxygen content - I presume this could reduce flying efficiency.
Low air temperatures affecting the operation of the electronics inside and perhaps the control surfaces.


texts:
How is flame stabilization done in a jet engine combustion chamber?
What are the various ways of doing this?
What are the challenges/ problems faced?


texts: How can take-off slots suddenly become available even when airspace is congested?

texts:
Here is something that happened to me: my flight was 3 hours late because the plane arrived late. We were told that a further 3-hour delay was expected because our flight had lost the slots it had in the air traffic system, and we couldn't immediately get new slots due to very high congestion in the skies.

Nevertheless, all the passengers were immediately boarded, all the flight procedures were initiated (safety film etc.), the plane taxied towards the runway and immediately departed.

After landing I asked the pilot how the 3 extra hours we had to wait due to congestion suddenly "disappeared". He told me that congestion is fluid and sometimes things change.

How can things change so much so quickly? Is the pilot's explanation plausible or is there another story behind what we were told by the airline?


texts: Who would be allowed to operate with no navigation lights over a populated area?

texts:
I know little about aircraft, FAA or FARS, but I've tried to research something I saw one evening without much success. I was hoping an expert could chime in.

One evening, while watching for satellites, I saw a black blob cross the sky, and thought that was really strange. A few minutes later, it happened again, in nearly the exact same position, and in the exact same direction, but this time I realized it was accompanied by the sound of a prop plane. This went on a few times, each time the sound of the prop plane and then a black blob going south to north with no lights. Eventually, the 4th or 5th time, an SWA 737 was coming in for a landing at a nearby airport, MAF if it's relevant, perpendicular and in the path of the dark prop aircraft, when suddenly the dark aircraft lit up it's navigation lights. I could only assume it did that because of its vicinity to the commercial flight

From what I've read, all aircraft abide by FAA regulations, even the military in general. Does anyone have any idea of who would be allowed to operate an aircraft, with no navigation lights, over a populated area? My only guess is that maybe federal law enforcement would be able to do so?


texts: What is the floor of the class E airspace near KRHV when the tower is closed?

texts:
See the attached diagram snippet for KRHV in Northern California. The chart supplement says that when the tower is closed the airport surface is class G. At this time, what is the floor of class E in areas "1" and "2"?

As you can see, class E starts at the surface around the Fairgrounds visual reporting point. Class E starts at 700 ft. AGL South-West of the airport and at 1,200 ft. AGL North-East of the airport. What happens in the middle in areas "1" and "2"? Does the magenta vignette cut through class D as shown by the red line or follows the border of class D? Again, this question is only relevant when the tower is closed.


texts: What causes descending aircraft to make a noise like a giant blown bottle?

texts:
I've lived for years about eight miles NW of Boston's Logan Airport. Although I can't say we get a lot of aircraft noise, once in a while, due to winds or air traffic, there will be a long line of planes traveling right over my house, perhaps 6000-8000 feet up, descending into Logan. At night you can sometimes see three in a row, with a fourth one turning on its landing lights.

Most of the time the overhead planes sound mostly like a roar with some jet whine. However, once in a while a plane will suddenly start making a very strange sound like an enormous blown Coke bottle. Often the pitch will descend during a half dozen seconds, stay constant for a dozen seconds, and then rise again until the sound disappears.

My best guess is that the sound is caused by the pilot lowering the wheels during their descent, and that it only happens on certain models of aircraft. As the wheel well covers open, the air blowing across the wells sounds like that giant Coke bottle, with the pitch decreasing as the opening increases. On certain models, the covers will then close once the wheels are down, causing the pitch to go back up.

(Edit: it's been pointed out that gear isn't dropped until 2000-3000 feet, so in my case that isn't the sound. So, I've removed all those videos, cool though they may be.)

Is my guess right? What model/manufacturer of large jet would make this sound?


texts: How are timed flybys executed, and what are their accuracy?

texts:
Thought experiment: Suppose I am equipped with an ideal automobile which can reach speeds of 700mph.  On a highway, I can deftly maneuver around light traffic to achieve an average speed of 500mph.  A friend, standing on an overpass, dares me to pass under him at high speed at a precise moment in time some distance in the future giving me enough time to reach my destination (if perhaps a bit early or late).

I would find this maddenly difficult.  Likewise, aren't timed flybys difficult?  How are they executed?  Given an F16 with an average pilot, how accurate could a stadium flyby be timed?  What technology is used?

Edit:  Let be more specific.  I.  What are the exact procedures used by a flight team performing a timed stadium flyby.  II.  Given a highly trained team, what is the expected deviation from desired flyover team and actual flyover time?

I still don't think this question has been answered in detail.  Also, there must be some technique that dates from the pre-GPS era.  Even with GPS, I suspect (but I may be wrong) that the answer is more than staring at a GPS and intuiting the appropriate adjustment in speed.


texts: Where can I get airport diagrams of non-towered airports?

texts:
I'm trying to find a couple of airport diagrams for right now: X26 and X59.

Neither of them are listed in the Chart Supplement or on the FAA site.
All I could get were those shabby diagrams presented by Airnav and Skyvector and sorts, and Google Earth images, both of which are not current. (The runway numbers are different from what are actually designated (painted) and used.)

Does anyone have a better idea about where to find the airport diagrams?

Plus, what the heck is the order of those airport diagrams listed in the Chart Supplement?! I couldn't find any rules.


texts: Documentation about "drag stabilized flying wings using non-reflex airfoils"?

texts:
What provides lift is the wing, but it is unstable without one stabilizer.

Flying wings airfoils, or reflex airfoils, carry their stabilizer inside them, through a reversed camber of the trailing edge section. Those airfoils provide less lift and more drag than "standard unstable cambered" airfoils.

Long time ago I (don't know where anymore) saw images of one particular wing longitudinal stabilization method, which could allow one "standard unstable high lift" or let's say Clark Y airfoil, to fly stabilized by the drag produced by one surface placed quite far above the trailing edge.

This looked like this, and models of it fly pretty well :

Who thought about this configuration and does anybody have documentation about this?

What interests me in this is : What kind of max L/D ratio and finesse could this Clark Y (or RG 14 or else) drag stabilized config could reach, compared to reflex airfoil (Eppler 187 or else) of same wingspan, same wing loading, same geometry glider.

Note the impossible sustained reverse flight.


texts: How much power does the APU generate in a Boeing 737-300?

texts:
I have just watched Mayday episode 11, season 11, "Nowhere to Land" about TACA Flight 110 incident and I was more than surprised to learn that:

APU must be turned on,
APU needs about 5-10 minutes to start powering anything,
APU can be used to power lights in the passenger cabin (???).

This is the exact flow of events (plus voice description) as it is shown in above cited episode:

a pilot is shown turning APU's switch,
narrator explains that a certain amount of time must pass before APU starts working,
lights in passenger section are turned on after this period of time passes.

Contrary to the above, I was always told (based on Air Transat Flight 236 incident, shown in season 1, episode 6, "Flying on Empty" of Mayday, and based on other sources):

APU is deployed automatically (gravitational solution) whenever power from engines is lost,
APU starts powering equipment nearly immediately,
APU is able to power basic instruments only, even pilots cabin remains dark, not to mentioning passenger sections.

What is the reality?


texts: Can a Rutan Quickie be made into a legal Part 103 Ultralight?

texts: I was was thinking about buying a 80s rutan quickie q-1, it has a 18 hp motor. I want to get a ultralight but I like this one because it is fast. Can I get a motor that would be within the requirements? I don't know how I would be able to make this an ultralight. Iwas wondering if a Rutan 277 engine would work well in it and if this would be in the requirements


texts: "Cancel altitude restriction." Under ICAO rules, does it cancel all altitude restrictions on a SID or STAR chart?

texts: Let's say there are altitude restrictions at 5000ft, 11000ft, 15000ft, 18000ft on a SID chart. While you were following the SID (under ICAO rules), the Departure tells you "Climb 12000ft, cancel altitude restriction." Does this instruction cancel all altitude restrictions on the chart or only restrictions below 12000ft?


texts: How does landing performance differ on water vs. ice vs. paved/grass runways?

texts:
It's a follow up from How do aircraft brake when using skis?

Can someone give me data about difference between landing distance for each environment ?

Paved
Grass
Water
Snow/Ice

Any aircraft is fine, provided it's fitted with brakes used during wheels landing.
Ideal answer would be comparing the same plane fitted with different landing gear on similar wind condition/ pressure


texts: Does FAA simulator (AATD/BATD) count toward experimental rating 1,000 hours requirement?

texts:
In the USA, a pilot can obtain an AEA (authorized experimental aircraft) rating to fly demilled surplus military turbojet-powered aircraft under FAA 5-1580(A).  Part of its requirements are to have logged a minimum of 1,000 hours pilot flight time, including 500 hours as pilot in charge.

A student pilot can NOT log hours in a FAA-aproved AATD or BATD simulator, unless an instructor is present.

But, AFTER someone has their private pilot's license, are they then able to log some hours in an FAA-approved AATD or BATD solo (without instructor) toward their 1,000 and/or 500 hours required for the experimental rating?  (Perhaps even using a simulation of the surplus military aircraft they want to have authorization for?)  Or, is that level of distrust from un-verifiability still there after someone has their private pilot's license?


texts: What options would Qantas Flights 7/8 have in case of emergency?

texts:
Route For Qantas 7&8

As this route shows, once the flight exits SYD, then all it has nearby is just the great pacific ocean. In such a situation, if it hits some emergency, what all options would it have, if it wants to land, due to some emergency like a patient on board?


texts: What is meant by a “cold soak" of an APU?

texts: What is the exact meaning of "cold soak" of an Auxiliary Power Unit (APU)? Is it to do with long flights at high altitude and the fuel getting cold? Will it affect the ignition of the APU? Can anyone tell how this affects the function of APU?


texts: How do I calculate aircraft range with these parameters?

texts:
The parameters are:
MTOW, MLW, MZFW, OEW, maximum fuel weight, fuel flow rate and true airspeed. Measured in lbs and kts. Not given drag so unsure how to apply Breguet equation. Trying to construct a payload range diagram!


texts: Why this P-51 limitations placard for diving?

texts: I noticed that this placard has different diving speeds related to altitud. My guess is that those values are a safety speed to prevent going into regions close to Mach 1. I know that the speed of sound is related to temperature. I did some calculation: 260 mph (IAS) is about 525 kts (TAS) @ -56.6ºC which is standard temperature at 40000ft, that's pretty close to the speed of sound. Am I guessing wrong or those limitations have another purpose?


texts: Does a constant speed prop maintain the optimal angle of attack at all time?

texts:
From an answer on this site:

The governor just knows: Speed too fast, flyweights move out, routes
pressure to move the blades more coarse; speed too slow, flyweights
move in, routes pressure to move the blades more fine. How coarse or
how fine, the governor does not know or care.

So a constant speed propeller will not maintain the best AoA through the flight, at the end of the day it will allow to fly at maximum prop. efficiency only selecting the appropriate MAP/RPM for the flight condition, otherwise it will just keep the rpm selected.
Am I correct? Or am I missing something?


texts: When the angle of attack is increased does the air flowing below it slow down

texts: So the air above the wing flows faster. So it creates low pressure above the wing. The air flow below the wing, is it slowed down by the increased angle of attack or does it stay the same? So is the higher pressure on the bottom of the wing relatively higher then the bottom or does the airflow on the bottom slow down beucase if the increased angle of attack?


texts: Are there any restrictions on long overwater flights by private aircraft?

texts:
It is talked about in many questions here that (with the exception of older 3+ engine aircraft) airlines and their planes must be ETOPS certified if they are going to fly more than 60 minutes away from a suitable diversion airport.

Are there any similar restrictions for private flights?

If regulations differ, assume the flight is between the US and Europe in a US or European registered plane.


texts: Can horizontal stabilizer trim be worked independently (each side)?

texts:
I notice most jetliners have a big trim wheel on each side of the center console.  This wheel is black with white stripes, and notably turns on its own via the autopilot.

Two large trim wheels: And obviously, most jetliners have two horizontal stabilizers or stabilators.

Can each side be trimmed independently of each other?  That is, does each big wheel control one stabiliz/ator and can they be unlocked and operated in different directions if need be?


texts: Can a CFI whose instrument rating isn't valid legally offer instrument instruction?

texts: Can a flight instructor whose instrument rating isn't valid legally offer instrument instruction?


texts: What is this yellow tube (lower right quadrant of the picture) which is blowing air into the airplane while it's at the terminal? You can see the open hatch on the bottom of the jet through which it's connected.


texts: Why do we calculate the pitching moment coefficient about quarter chord point?

texts: Why do we calculate the pitching moment coefficient about quarter chord point, when force and moment system can be transferred to any convenient point?


texts: What is the true meaning of the word "roger" when used on the radio? What is its origin?

texts: When pilots learn to talk on the radio they can generally learn that the word "roger," when used on the radio, is a way to acknowledge that a message was received. What is the textbook definition of the meaning of this word when used on the radio? Also, what is the origin of this word?


texts: Is there any ATS into the Special Use Airpaces (SUA)?

texts: The SUA has its own characteristics and limitations. Is there any unit responsible for providing separation, control or information, for pilots flying into or across any SUA?


texts: What is the make and model of this biplane?

texts:
This photo is of one of my friend's great grandfather:

We wish to commemorate a museum in his name as he was a highly regarded person in his area, so we wish to show this photo in the museum with details of the plane.


texts: How is minimum runway length related to V1?

texts:
1) Is $V_1$ used to determine minimum runway length? How is $V_1$ calculated?

2) If it is used to determine the minimum runway length, and for example we have a runway of 8000 ft and my airplane's accelerate stop distance required (ASDR) is 4000 ft and takeoff distance required (TODR) is 5000 ft, can my $V_1$ be as low as 15 kts? Since (let's say) below 15 kts, of course you will have the 4000 ft required to stop and also have enough distance to takeoff with 1 engine inoperative.

3) Let's say we have a very long runway so an airplane can make a rejected takeoff even at rotation speed ($V_R$). Can $V_1$ be the same as $V_R$?


texts: In USAF are people WSO by choice or is it because they didn’t make the cut to be a pilot?

texts:
Generally, is a US Air Force Weapon Systems Officer (WSO)

someone who wanted to be an WSO or is specifically assigned and trained to be an WSO from the start, or

someone who failed flight training in some way?


texts: What noise reduction measures were taken in the time between hush kits and chevrons?

texts:
In older jets such as 727 hush kits are used in the engines to reduce noise. In very modern jets such as 787 or 747-8F, chevrons are used for the same purpose. What happened in between? The switch to high bypass ratio turbofans alone is sufficient an improvement in engine noise that no special noise reduction device is required? (Not even hush kits?)

A hush kit:

A chevron:


texts: Why aren't isentropic noses and tails used in supersonic aircraft?

texts:
An inside out paraboloid would theoretically produce isentropic compression for an inlet cone. But this question is about nose and tail cones on fuselages, and leading and trailing edges of wings.
An isentropic nose would preserve pressure in the region surrounding the aircraft, so that more of it may be recovered at the tail. This effect, if course, may not be very significant. It would also reduce aerodynamic heating.
An isentropic tail would enable better pressure recovery following the expansion fab, and thus reduce drag.
So, why are these shapes not used?


texts: How does a coaxial rotor helicopter achieve yaw?

texts:
Without a tail rotor, how does a coaxial rotor helicopter achieve yaw control? Does a coax have to bank in order to turn?

The link goes to wikipedia's article, and down a ways it says:

  Rotational maneuvering, yaw control, is accomplished by increasing the collective pitch of one rotor and decreasing the collective pitch on the other. This causes a controlled dissymmetry of torque.

However, I cannot understand what it's saying. AFAIK both rotors always spin at the same RPM because the mechanical engine links are built that way and it's set in stone (correct me if I'm wrong). So I can't see how one rotor makes more torque.

EDIT: related, is this kind of yaw, however it's achieved, slower or faster than yawing in a conventional tail helicopter?


texts: Who has the authority between captain and first officer in emergencies?

texts:
Yes I know, Captain has authority over First Officer.

I was reading about Airblue Flight 202 and according to the investigation, First Officer said these words 40 seconds before crash:

  Sir turn left, Pull Up Sir. Sir pull Up.

Although many sources have questioned the investigation and its subsequent report, because of several facts including how the captain with over 25,000 hours and an unblemished flight safety record could make such mistake when he is so much familiar with the terrain etc., my question isn't about that.

What I want to know is that in case of an emergency or a similar incident of an imminent crash (as mentioned above), can a captain order the First Officer not to touch anything, or ignores his warnings or simply not listen to him at all? What the First Officer has to do or can do?


texts: How does an airplane do a Kulbit manoeuvre?

texts:
Some time ago, I came across a GIF of a Russian military airplane doing a Kulbit manoeuvre (Probably for showoff). How, in terms of control surface movement, does an airplane to the Kulbit?

Source: Reddit


texts:
I would like to know where ideally it is to be sat on an Emirates A380 to get a nice picture of the wing and wingtip as well as the outer landscape?

LHR-DXB 7:50 P.M


texts: Why autogyros use pusher-, whereas, piston-engined planes use puller-configuration?

texts:
I found that most modern gyrocopters use a pusher-configuration, whereas, most piston-engined planes use puller-configuration.

Since the pusher-configuration has major disadvantages, are there specific advantages for autogyros?

Visibility is a positive effect of pushers, but this would also count for normal planes.


texts: What is the difference between OAT, RAT, TAT, and SAT?

texts:
When I first started flying jet aircraft, I found different instruments that measure temperature in different ways and it was quite confusing.

What is the difference between Outside Air Temperature, Ram Air Temperature (RAT), Total Air Temperature (TAT), Static Air Temperature (SAT), and any that I might have missed?


texts: Relation between altimeter setting (QNH) formula and the barometric formula

texts:
I'm searching for a reliable source for a formulization of the QNH adjustment to the barometric altitude. I found this document from weather.gov that gives a formula for the Altimeter Setting, which is QNH if I'm correct. If I replace the formula's values with the appropriate constant names, it becomes this:
$Altimeter Setting (QNH?) = \left ( P - 0.3 \right )\left ( 1 + \left ( \left ( \frac{P_{0}^{\frac{L.R}{g}} L}{T_{0}} \right ) \left (  \frac{H}{\left ( P - 0.3 \right )^{\frac{L.R}{g}}}\right ) \right ) \right )^{\frac{g}{LR}}$
I also know the following formula from the US Standard atmosphere (which is identical to the ISA standard atmosphere up to 50 km):

Which can be expresses like this (for troposphere):
$P = P_{0} \left [ \frac{T_{0}}{T} \right ]^{\frac{g.M}{R.L}}$
Symbols and their meanings for extra information:

$P$: Pressure at the airport
$H$: Altitude at the airport
$P_{0}$: Standart pressure (1013.25 $hPa$)
$T_{0}$: Standart temperature (288.15 $K$)
$L$: Temperature lapse rate
$R^{*}$: Universal/ideal gas constant
$R$: Characteristic gas constant
$g$: Gravitational acceleration of Earth.
$M$: Molar mass of dry air

So, my questions are twofold:

Are these formulas actually different reperesentations of the same formula? I tried but I haven't been able to acquire the second formula from the first one.

What is the $-0.3$ for in $(P-0.3)$ in the first formula? Why is it there?


texts: What are the advantages and disadvantages of a monoplane, biplane and triplane?

texts: What are the pros and cons of a monoplane, biplane and triplane design; aerodynamics, efficiency, etc.?


texts: How do aircraft altimeters calculate altitudes accurately while airborne?

texts: While an aircraft is airborne, the local barometric pressure can change, causing an altimeter to no longer display the correct altitude. How are altimeters re-calibrated to display the correct altitude, or there are other methods to accomplish that?


texts:
Perusing through the A/FD in the United States I see that some runways have declared distances while others do not.

What is the meaning of:

TODA
TORA
ASDA
LDA


texts: When passing a waypoint, when exactly are we on the next leg?

texts:
When performing one of the procedures shown in the pictures below, when exactly do we consider ourselves to be on the next leg?

For example: for the fly-by waypoint, when do we consider that we are no longer flying from the runway to Alpha, but we're now on the Alpha to Bravo leg instead? Is it in the middle of the arc, once we finish the arc...? For fly-over waypoints, I guess it's when we pass Alpha, but I'm not sure about that either.


texts: When does the FMS in the 737NG switch to approach mode?

texts:
I fly a B737-800, and we talk about when the FMS enters "Approach mode". At this point, the FMS will command the Vref (plus additive) at the appropriate flap setting. This is helpful to know especially when there is a flap malfunction.
When does the FMS switch to "approach mode" for calculating speeds, and where do I find this information? I haven't seen it in the FCOM.


texts:
When a commercial passenger airliner suffers a rapid decompression, it is critical that everybody on board gets oxygen quickly. In the passenger rows, oxygen masks connected to chemical oxygen masks will drop. In the cabin, the flight crew will pull out their oxygen masks, which are connected to pressurized oxygen canisters. The chemical generators will last for 10-15 minutes, but apparently the flight crew's oxygen supply will last for a couple of hours.

Why would the flight crew's supply last for so much longer? If the plane isn't at a breathable altitude after 30 minutes, it seems like it'd probably be unrecoverable, and the passengers will be in irreversible comas anyway.


texts: Does a 1lb crow expend only 7.68 Watts to fly at 37 km/h?

texts:
The Wright brothers and the 1 pound crow that flies at 37 km/h expending just 7.68 W

In an 1905 letter to Octave Chanute, Wilbur Wright evaluated the power, used by a 1 lb bird to fly at 34 ft/s, utilizing a relation that can be rewritten as:

eff x Power = Thrust X Speed = Drag x Speed,

where: eff (the efficiency of the crow) = 75%, Drag/Lift = Drag/(mg) = 1/8 and mg = 1 lbf.

In consequence, Power = (1 lbf x (1/8) x 34 ft/s ) / 75% = 7.68 W.

  "The power consumed by any bird or flying machine may be figured from the formula wv/ac, in which w = weight, v = velocity, 1/a = ratio of drift to lift, and 1/c = efficiency of the screws or wings as propellers. In the case of the crow flying at 34 ft. per second, or 2,100 ft. per minute, I would fix the value of l/a at 1/8, and 1/c at 1/.75; when we have (1 x 2100)/(8 x .75) = 350 ft. lbs. per pound of weight.1 The minimum value of l/a may be rendered independent of velocity by regulating the size of the wings. The value of 1/c is about the practical limit of the efficiency of screws under usual conditions, and I see no reason for believing that wings are more efficient than screws, as propellers. It is quite incredible that, when flapping, the wing can be kept at the optimum angle at every point, as in soaring; and there are losses due to the fact that the pressure is not vertical throughout the stroke. Although I think 25 percent a fair estimate of the probable loss from both sources.
  Birds unquestionably develop power many times greater than is consumed by our Flyer, per pound weight. if you will fix in your mind the distance within which a small bird acquires full speed, say 30 miles an hour, and then figure the power necessary to accelerate its weight to this velocity, I think you will be astonished. I know I was almost dumbfounded, especially in view of the fact that the power available for acceleration is over and above that used in flying. I shall be curious to know what distance you fix upon as that within which a sparrow acquires full speed.",
  Letter of Wilbur Wright to Octave Chanute, Dayton, March 11, 1905

7.68 W/lb seems a quite low figure as long as, it's generally accepted that any model plane with less than 50W/lb is going to struggle (see The Watts Per Pound rule)

Does a crow only expend 7.68 W/lb or at least it is possible to build a model plane able to fly at 37.3 km/h (34 ft/s) developing just 7.68 W/lb shaft power?


texts: What is the difference between axial compressor blades and centrifugal compressor blades?

texts: Is there a particular difference?  The way they're overhauled is the same ? (I mean do we use the same overhauling methods ?)


texts:
I was just curious, in the past, smoking on planes was permitted.

What is the law surrounding smoking in your own private plane?


texts: Can TODA ever be shorter than TORA, under any circumstance?

texts:
I've always been told that TODA* = TORA† + Clearway.  I can't really imagine what a negative clearway would be, so that leads me to think that it is required that TODA >= TORA.  Interestingly, a colleague pointed out a certain airport (Invercargill, New Zealand - ICAO code NZNV) where the declared distances published by a certain source describe a TODA that is in fact less than the TORA.

My colleague and I are under the impression that some kind of typographical error has occurred when this source was publishing the data.  However, I can't help but think back to strikingly similar conversations we had after seeing a previously unheard of case where ASDA‡ < TORA.  As it turned out, the FAA had changed how Runway Safety Areas were considered, in such a way that it is totally possible for ASDA < TORA (and we've been seeing it more and more frequently ever since).

*TODA = Take-Off Distance Available†TORA = Take-Off Run Available‡ASDA = Accelerate-Stop Distance Available

TL;DR

I wanted to see if anyone has ever heard of any other case where TODA < TORA, under any regulatory agency.  What would the rationale be if that were the case?


texts: From an ATC perspective, what is an "arrival gate"?

texts:
I have seen reference to ATC assigned "arrival gates".
As a passenger, an "arrival gate" is something like B12 or D37, but I'm quite certain that's not what this is referring to.
From an ATC perspective, what is a flight's "arrival gate"?


texts: How long is the horizontal stabilizer on a Boeing 737?

texts: I can never find information about the length of the horizontal stabilizer all I can find is the height of the vertical stabilizer.


texts: Why does the CRJ100/200’s FMS miscalculate temperatures at altitudes in excess of 36k feet?

texts:
The CRJ100/200’s flight management system (FMS) apparently is not to be used to calculate engine thrust settings when the aircraft’s altitude exceeds 36,000 feet, due to internal calculation errors at altitudes this high:

The Pinnacle Airlines CRJ FCOM, volume 2, Performance, pages 50 through 52, dated June 2002, presented altitude and climb capability charts. Pilots were required to consult these charts anytime a flight was operating above 36,000 feet because of a flight management system (FMS) limitation above that altitude.77  [...]
[...]
77 FCOM volume 2, Operating Limitations, pages 30 and 31, dated June 2004, stated that “the FMS calculated thrust setting must not be used if the pressure altitude is greater than 36,000 feet.” The Bombardier chief pilot stated that the reason for the FMS limitation above 36,000 feet was because of the inaccurate calculations above that altitude. Further, according to Bombardier, at altitudes above 36,000 feet, the conversion from static air temperature to the International Standard Atmosphere (ISA) deviation is incorrect within the FMS, resulting in an error in the N1 indication at those altitudes.  [...]  Bombardier’s Flight Planning and Cruise Control Manual and Quick Reference Handbook contain charts that show the proper N1 indication for altitudes between 36,000 and 41,000 feet.  [NTSB/AAR-07/01, page 33 (page 45 of the PDF file); footnote numbering in original; my emphasis.]

Given that 36 kilofeet is well below the CRJ100/200’s maximum operating altitude,1 it seems surprising that the aircraft’s FMS was not programmed correctly for altitudes beyond 36k feet, that this wasn’t caught very early on, and that the FMS  software was not updated to correct this bug once it was discovered; why was the FMS misprogrammed in the first place, and why wasn’t it fixed?

1: The maximum operating altitude for first-generation CRJs is 41 kft, a full 5,000 feet higher.


texts: Why it doesn't matter if tail produce lift or downforce for neutral point position?

texts:
I am really strugle what neutral point represent and what it depends on..
In this link we can see how neutral point is calculated.Thay use wing and tail areas and distance  between aerodynamic center (L) to determine neutral point position (D).Calculation is set like tail produce lift..(So calculation is the same like you must find fulcrum at see saw..)
What if tail produce downforce(what is often case).If this tail in my example produce downforce,neutral point will move to the left,completly different position.
Does neutral point  dependt at change of aerodynamics forces at wing and tail,for example  when you change tail incidence,etc?

If I put aircraft in vertical position to eliminate torque by gravity,connect with joint so he can rotate, now must find place at plane which will not rotate(moment is zero) when is subject to airflow.
Is this place neutral point?


texts: What is this small black rubber strip protruding out of the flap track fairing of the A320?

texts: On the Airbus A320 wing there in whilst in flight a small black rubber strip protruding out of the flap track fairing. What is it please?


texts: What component of an aircraft generates its electric power?

texts:
What component of an aircraft generates the electric power to start the aircraft's engine?

For a Rotax 912 engine, I think the magneto generates the electricity, but I'm not sure; I also think about the ignition coil or electronic ignition.


texts: How do commercial pilots send distress signals?

texts:
If a commercial jet is in trouble, how does a pilot send a signal indicating distress? Does it take long?

For instance, behind reception desks in many institutions and executive offices, there's a hidden red button that, when pressed, calls security or the police. (I know this since I sit at such a desk.) Do commercial airliners have a similar switch, or do they need to radio in for help? What happens when such a transmission is received?


texts: How are winds aloft forecasts derived in the USA?

texts:
This question pertains specifically to the US NWS FB Forecast Product.

Winds aloft forecasts, technically the "Wind and Temperature Aloft Forecast (FB)", are issued 4x daily, at 00, 06, 12, and 18z. At each of these 4 periods, 3 products are produced: a 6-hour, 12-hour, and 24-hour forecast. How are the forecasted values actually predicted?


texts: Is there a way for passengers to know which runways their flight will use?

texts: When I fly, I like to see the airport when I take off and land. Is there a way I can know, in advance, which runway the plane is likely to depart/arrive from so I know which side of the plane to sit in?


texts: How much weight does a thrust reverser add?

texts:
How much weight does a thrust reverser add to an engine?

Let's take the CFM Leap 1B as an example, which powers the new version of the Boeing 737. This engine can produce up to 130 kN of thrust for takeoff, and has a dry weight of 2.78 tons. I could not find how much weight is the thrust reverser system. Closest thing I found was this FlightGlobal article which at least talks about it, but doesn't give numbers.

One purpose of this question is to compare it to old-school drag chute system. I will open a separate question on that.


texts: Is there a name for aircraft weapon load photos?

texts:
I remember as a kid I had a couple of books full of spec sheets and big glossy photos of military planes with every standard piece of weaponry laid out in front of them, something like this (c/o Tech Sgt. Robert Horstman/US Air Force via Business Insider):

Is there a standard (official or unofficial) name for this kind of staged photo?


texts: Are turn rate indicators calibrated to a certain speed? If so, what speed?

texts: Are turn rate indicators calibrated to a certain speed? If they are, what speed are they calibrated to, and why aren't all the turn rate indicators calibrated for the same speed?


texts: Can small airplanes dump fuel during flight?

texts:
Can small airplanes, such as a Cessna 172, dump fuel during flight?

My understanding is that large commercial passenger aircraft often have the capability to dump fuel during flight, as can many military aircraft.  However, is that capability available for small 2 or 4 seat planes?  How big does a plane need to be before a fuel dump capability becomes useful?


texts: Can a delta wing fighter engage an arrestor net without its main landing gear?

texts:
A delta wing fighter aircraft with underwing drop tanks while landing loses its main landing gear, but the nose wheel is extended. Is it an option for the pilot to engage the barrier net of type EP-15 or MENA-30 at the end of the runway, or will the pilot eject?

Which is the safest and why?


texts: What is the relation between aircraft descent rate and speed?

texts:
I am an ATCO working in India. I am trying to understand why an aircraft's rate of descent increases, when its speed increases. I am particularly interested in how it relates to jet engine aircraft.

Is it the same for aircraft climb rate?


texts: What's the reason for this frog finger shaped parking lots at Köln/Bonn airport (CGN)?

texts:
Most aprons of international airports are vast areas paved with asphalt or concrete. However, I noticed this structures in the south of Köln/Bonn airport (CGN) (Google maps link):

Does anyone know what's the reason behind this unusual shapes?

EDIT:

Just found the Royal Airforce Base Brüggen with lots of dispersal areas. Some with hangars, some with banks of earth like in the black/white picture in aeroalias' answer. It's also a perfect example for the conceptional layout. (And between the areas in the south, there are even typical bunkers for explosives)


texts: Why does operating the rudders in the engine slipstream offer improved rudder authority at low speed?

texts: The above question is usually presented as an advantage for H-tail configurations. How does it help?


texts: What could these possibly incorrectly translated numbers for aircraft speed have been?

texts:
Yesterday I was watching a show about Air Crash Investigation, the
Air France flight 447 case involving an Airbus A330-200.

I was watching it with Spanish voice dubbing and the weird part is that the narrator said the plane...

reached a final speed of 13,000 km/h
started falling at 7,000 km/h
crashed at 200 km/h

The only speed value that makes sense to me is the last one: 200 km/h.

My guess is that something was missed in translation. What is usually the speed measure for aircraft in the US?

I also thought about the 7,000 figure, and perhaps instead of speed in km/h it meant altitude in feet?


texts: Why is the airflow in airline cabins downwards?

texts: Air is distributed from overhead outlets and flows downwards towards the floor. Since the exhaled air is hotter than the air around, and tends to concentrate towards the ceiling, wouldn't it make more sense to pump air from the floor upwards towards the ceiling?


texts: How does the ADS-B signal transmission randomization work?

texts:
As the FAA mentions, the ADS-B messages like Identification, Position and Velocity are transmitted randomly uniquely between $ 04 \pm 02 $ sec.

How does the transmitter define that randomization? Is it standard or fixed or else who decides that?


texts: Are there any passenger aircraft with no cabin access to/from the cockpit?

texts:
Most passenger aircraft (airliners and business aircraft) have an internal door or doorway connecting the cockpit area to the main cabin; are there passenger aircraft where there is a solid partition isolating the cockpit from the passenger cabin, and passing between the two requires exiting the aircraft?

Yes, I know that many early passenger aircraft had enclosed cabins with separate, open cockpits; I'm wondering about aircraft with an enclosed cockpit and a separate, enclosed cabin.


texts: How does a jet's throttle actually work? What does it do to the pressure chamber and the fire output controller?


texts: How to start up a Lockwood-Hiller Valveless Pulse Jet?

texts:
So me and my group mates in university got a lockwood hiller valveless pulsejet manufactured, and there was one error in manufacture. We are having trouble with trying to start the engine as demonstrated in the attached link. Is there an error in the engine you can see?
One manufacturing error we identified is that the exhaust cone is slightly at an angle and is not exactly parallel to the combustion chamber+intake which looks something like the attached. Could making it parallel solve it?
Also, would putting the gas cylinder upside down solve it?


texts: What is the purpose of the extra horizontal and vertical surfaces on the tail of the Beechcraft 1900?

texts:
I am building a very large(11ft span) twin engine RC airplane that is loosely based on the Beechcraft 1900D design.

I can't help but notice the extra horizontal surfaces sticking out of the aft fuselage and the vertical surfaces hanging down from the ends of the horizontal stabilizer.

Could it be that after test flying they decided that the center of pressure needed to be moved further aft, but maybe it cost less to add new small surfaces instead of altering the design of the current surfaces?


texts: Why does ATC ask emergency aircraft about fuel on board?

texts:
From what I hear, it looks like it's a standard procedure that ATC asks about fuel on board whenever an aircraft declares an emergency. Do they need the information for their own planning purpose or just to pass it along to the fire crew so that they get prepared for possible emergency situations like a fire upon landing?

I thought the second was the correct reason, but the fact that some pilots report fuel in remaining time, not in pounds, gets me confused.


texts: Why do some canard aircraft have dihedral on their canards?

texts:
For instance, Rutan's Solitaire and Steve Wright's Stagger-EZ. What are the benefits of having a dihedral on the canard?
It seems like the canard dihedral increases yaw instability, and requires a bigger vertical stabilizing surface. Yet there are flying GA airplanes and sailplanes using canards with dihedral, and they've surely thought of this. What's the reason for that?
(My opinion-based hypothesis is that it's about very stalled AoA behavior, where canard dihedral may naturally slow down some flat spin, and help with recovering from it; still, I cannot find any references about this, and it may also be a very wrong statement as long as it's opinion-based.)

(Rutan's Solitaire)

(Wright's Stagger-EZ)

(Saab Gripen)
Edit:
Gripen also has dihedral on canard surface, however since those are full moving surfaces with high sweep angle, depending on the angle of attack, those surface viewed from the front, display either dihedral, no dihedral, or anhedral (if very positive canard AoA)


texts: Is it safe and effective to have "glider pilot mentality" when landing single-engine fixed-wing aircraft?

texts:
I am a low-time pilot, of approximately 200 hours. I trained on the DA20 and DA40, designs that are derived from the Diamond touring motor glider design(s) of the early 1990s. I anticipate getting my Glider rating this summer in the US. As I've considered getting my glider rating, I've noticed a habit that I've developed that closely matches the "glider pilot mentality" which does not seem so prevalent in my training for ASEL.

I've always preferred using a forward-slip for landing with the engine idle, as opposed to using the throttle to adjust the descent angle. I attribute this to multiple factors, such as being aware of the design history of the DA20, training with its more "glider-like" characteristics, and a general paranoia of the engine quitting on base or final.

This brings me to the following questions: What are the safety considerations for this type of approach? Are there limitations on the use of sideslip on light airplanes?

Edit: Supplement questions, for possible merge or replacement of above. (Taken from my comment below)

Instead of puttering in using throttle, why don't we use side slips all the time?
Why don't most/more GA aircraft have spoilers or dive brakes?
Is the mentality of "every landing is an engine-out landing" creating more danger than it alleviates?


texts: Can the lift equation be used for the Ingenuity Mars Helicopter?

texts:
I am currently working on a basic simulation of the Mars Helicopter Ingenuity, and I am having trouble interpreting the outputs I am receiving from the lift equation. The equation reads as follows:
L = Cl * A * .5 * r * V²
L is lift in newtons, Cl is the coefficient of lift, A is the area of the circle traced by a blade in one rotation, r is atmospheric density, and V is the velocity of the blade. Ingenuity has two rotors 1.2 meters across, each with two blades. For this example, let's assume a rotation rate of 2400 rpm. The coefficient of lift is 0.4, the average for small helicopters. Atmospheric density on Mars is 0.020 kg/m^3. The velocity is taken 1/2 way down the blade and is found by using ((1.2/2)π * rpm / 60). Plugging in the values for Ingenuity gives:
102.871 = 0.4 * π(0.6)² *.5 * 0.020  * 5684.858 * 4
The 4 at the end is added because Ingenuity has four blades, each generating its own lift in accordance with the lift equation.
Dividing the lift by the mass of Ingenuity (1.8 kilograms) gives an upward acceleration of 57.15 m/s². Unfortunately, this number is too large to be accurate. Martian gravity is only 3.711 m/s², and whatever drag that will be generated by the thin atmosphere is likely to be insignificant in relation to such a large upwards acceleration.
So, the question is, how should lift be calculated in this case? Am I using the lift equation incorrectly, or is it simply not applicable to small drones like Ingenuity? If you have any resources for calculating lift more accurately in this case, please share them.
Thank you.


texts: How to choose between BasicMed an a Class III Medical?

texts:
I'm due for a medical this year, and my last one was before the BasicMed program existed.

I'm a VFR PPL, flying small planes with 6 people or less.

Is there a clear reason to use Basic Med or Class III Medical?


texts: Is there a relation between the Mode 3/A Code and the ICAO aircraft address?

texts: I would like to know is there is any way to match mode 3/a code (which is assigned by ATC to aircraft) and ICAO address of the aircraft. I mean how mode 3/a code is assigned to each aircraft by ATC? Is that unique for that day or certain time period? Is it possible that same address is assigned to more than one aircraft? Is there any relation with aircraft's own 24 bit ICAO address?


texts: Can GPS be used in lieu of DME for instrument approaches?

texts:
Instrument approach charts list the equipment required to fly them in their name. For this example let's say we have an ILS or LOC/DME 36R approach. This approach requires an ILS receiver for the ILS portion, or both a LOC and DME receiver for the localizer only portion.

Let's also say we're flying an airplane that has an inoperative glideslope receiver and is otherwise /G equipped with an IFR-certified and up-to-date GPS. Can the GPS be used in lieu of DME in this case?


texts: Can a non multi-engine rated pilot get a complex endorsement in a multi-engine aircraft?

texts: I was wondering if a pilot with only an SEP can get his/her complex endorsement in a multi-engine aircraft? I would guess not but since I didn't find any clear info or FAR that sates you can't, I just wanted to be sure.


texts: How many hydraulic systems does the Boeing 757 series have?

texts:
How many hydraulic systems does the B757 series have, does it have a Power Transfer Unit (PTU)?

What is the operating pressure of the hydraulics in the Boeing 757?

How big is the hydraulic reservoir?


texts: If I do PPL ground school online, do I have to do all of it?

texts:
I am not doing normal ground school (I chose to do it online). I have passed my PSTAR, and will be doing my ROC-A in the upcoming weeks.

With this in mind, must I do the entire online ground school course? I do not know if my instructor (or worse, the FAA) will check if I have finished all of the online work.


texts:
A few days ago I flew on a Boeing 737-900ER. Luckily I was sitting just beside the left wing, seat 26B. I observed that the spoilers were activated (opened) just after the pilot spoke on the Passenger Address System announcing that the airplane was preparing for landing (if I was not mistaken) and began to descend. The spoilers then opened for around 3-5 minutes (picture 1) and then closed again (picture 2) until it touched down. In flight they were not as fully activated/opened as when the airplane landed.

My question:

What is their purpose? Are they brakes?
If they are brakes, does an airplane need brakes in the air?
If they are brakes, is not more efficient to reduce the engine's power rather than to keep it constant power but brake to slow down?


texts: Who first coined the phrase "aviate, navigate, communicate"?

texts:
The phrase "aviate, navigate, communicate" describes the priorities of tasks for a pilot. It is applicable to a wide variety of situations, including military scenarios and emergencies.

Who first introduced this phrase, and when did it first appear in the aviation community?


texts: Is there a way to **decelerate** significantly without an "eyeballs-out" sensation?

texts:
I'm not sure how to describe this, but the problem came about as I was computing some acceleration profiles. Let's say you want to get up to Mach 3 (939 m/s) quickly. If you accelerate at 3 g's, this will take 31.923 seconds (not bad), and in level flight would cover a ground path of 14.991 km (kind of a lot, but not really comparable to typical flight lengths).

Only problem is, when it comes time to land, you have to slow down. If you want to do that quickly too, well, 3 g's in the "eyeballs-out" direction is a little hard on the eyeballs. Doing 1 g would take 3 times longer but also cover a ground path more than three times longer because of that pesky time squared in the equation for uniform acceleration ($\Delta x = \frac12 at^2$, if initial x and inital v are zero).

So you could gradually slow down over an even longer distance, or...is there some other, quicker way that doesn't involve much eyeballs out? Could you maybe fly a circle over the airport and decelerate that way, so that you feel the g-force mostly pointing down into your seat? Is there some other way you could "cut into another plane"?

The goal is to decelerate quickly so that the average flight speed (over the whole journey) is very close to Mach 3.


texts: What is the operational advantage of starting an RNAV SID with a VI-CF leg combination?

texts:
I am examining Standard Instrument Flight Procedures, mainly from FAA's charts and Coded Instrument Flight Procedures ARINC-424 file (CIFP). I am keen in understanding the operational advantages or other criteria by which a procedure designer would choose a certain leg combination over another.

As far as I could tell by searching through the aforementioned CIFP file, the following leg-combinations are mostly used for the first couple legs of an RNAV departure procedure:

VA (Heading to Altitude) -> DF (Direct to Fix)
VI (Heading to Intercept) -> CF (Course to Fix)

The first leg can also be DF, CF or TF, as it is stated in FAA's 8260.58A Performance Based Navigation manual, in Chapter 5. Departure Procedures, section 5-1-1. General.

For an example, take BRYCC4 Departure and its respective narrative page. Takeoff from runways 16L/R uses a VA-DF leg combination ("Climb heading 173° to 5934, then right turn direct to cross MUGBE at or below 10000..."), whereas takeoff from Runway 17L uses a VI-CF leg combination ("Climb heading 173° to intercept course 127° to cross GISTT at or above 7000...").

I can understand the need for a VA leg before a turn, since the aircraft is required to climb to a certain altitude (eg. for LNAV engagement or for obstacle clearance) before the first turn. However, I have a difficulty grasping the circumstances under which a VI leg is a more preferable choice.

Could someone point me to any source material that describe the criteria on which the decision about the leg combination during takeoff is based?


texts: What are these markings on the A380 wing?

texts: There are some "markings" over the wings and the horizontal stabilizer. Could somebody explain what they are?


texts: At which angle tiltrotor's rotors generates more lift?

texts:
[Tiltrotor 1]

                        [Tiltrotor 2]

I can't name these tiltrotors. I just want to know which of the tiltrotors generate more lift considering aerodynamics and based upon the rotors horizontally tilted or vertically. I used these images just to show an orientation of rotary wings at which angle they are tilted not for differentiating these two models. And what happens to the lift generated by the rotors tilted 45 degree to the axes.

Note: Only concerned with the rotary wing either horizontal or vertical inclined but not whole aircraft design.


texts: What is this USAF transport aircraft from possibly the 50-60s?

texts:
I came across the following image (scan of a photograph) in an archive of photographs related to the 1962 Sino-Indian War.

Which particular aircraft could this be?
Update: This answer identifies it as belonging to 322d Airlift Division.


texts: Where can I place an engine in a twist morphing wing?

texts:
I am designing an electric aircraft with a wing that is completely based on the idea of biomimicry, whereas the wing has multiple winglets and can also morph by twisting. It is more like an experiment to check about the possibilities of a commercial aircraft with the ability to morph.

Where could I possibly place the engine if my wing is going to be able to twist?


texts: What do firefighters do on ordinary days?

texts:
Some not very busy airports can have no even a minor incident for years and accident probably won't happen in a major airport during several decades. Training of course is done sometimes. I don't know how often though. This has to be the most boring or the best job if you wan't nothing to do. I think you can spend all your career without putting out single real fire or doing real rescue.
So what do firefighters do day to day?


texts: Why do jets with 3-D thrust vectoring never hover nose up, but instead move slowly forward?

texts:
I've seen several impressive videos of fighter aircraft moving incredibly slowly by essentially hovering on the engines, balancing using thrust vectoring. For example:

This Su-10

This Su-37

Large RC jet aircraft often take this maneuver one step further, by coming to a complete stop in the air before accelerating away. Do airshow pilots choose not to attempt to come to a stop because it's too dangerous, or is there some hardware difference between RC jets and military jets that limits their ability to hover in place?


texts: Why is there a difference between the procedural track heading and final approach course at Fort Hood (KGRK)?

texts: Looking at the NDB RWY 15 into Fort Hood/Killeen, why is the procedural track from OKEST showing a heading of 151 degrees when the final approach course heading is 150 degrees. Is that simply a typo? The best answer I can come up is that from OKEST to the LOM is 6.3NM on a heading of 151 degrees. Is the 151 heading to GRK VOR or to the LOM using the NDB? Any thoughts?


texts: How can the F-16 remain stable when there is a loss of hydraulic power?

texts:
Edit for justification:

This question is different from If the EPU (Emergency Power Unit) on a modern fighter jet fails, will the aircraft drop out of the sky? for the following reasons:

The question in If the EPU (Emergency Power Unit) on a modern fighter jet fails, will the aircraft drop out of the sky? asks if an aircraft drops out of the sky if the EPU (Emergency Power Unit) fails, for a generic aircraft. The accepted answer only briefly touches on the F-16, and certainly not in a way to answer this question. This question is specifically about an aircraft with RSS (Relaxed Static Stability), and how this relates to loss of hydraulics and power.

Question:

The F-16 has Relaxed Static Stability (RSS) to enable a high degree of maneuverability.

This causes the aircraft to be inherently unstable and RSS is corrected for by the on-board computer in real time, as part of the fly-by-wire system.

In the event of loss of hydraulic power, the ailerons cannot be operated, the on-board computer/avionics will also fail, if there is no power. The EPU (Emergency Power Unit) will re-establish hydraulic and electrical power, but this doesn't happen instantaneously. It takes some seconds.

During this critical window, what allows the F-16 to remain in stable flight in the context of RSS?

Reading this PDF it seems that the F-16 can be unresponsive to pilot input, yet remain in stable flight.

My question is, how is this achieved? How is it possible?

My own reasoning:

Either the F-16 is not as inherently unstable as I'm given the impression it is, or, there is enough hydraulic power and electrical power left in the interim between power from main hydraulics to switching to the EPU to allow the fly-by-wire system to keep the aircraft stable.


texts: can I do my PPLA license in spain even if I live in Germany?

texts:
I live in Germany but I was born in Spain, I wpuld like as a hobby, to get my PPLA license..
but I would like to do that in Spain, if so, can I still flight in germany?

is that possible?

Thanks..


texts: Which airport is featured in this Delta commercial?

texts:
I just saw a Delta commercial with a plane taking off from a runway with a 16R designation (thus, the plane in the commercial was departing from 34L). Does anyone know where this airport is? Climbing out, there appears to be a large body of water ahead, if that helps!

I had always heard that Van Nuys (KVNY) was the only airport with a 16R/16L runway designation, but the airport in the video isn't Van Nuys.


texts: Are there international standards to Air Traffic Control procedures similar to US standands?

texts:
In regards to air traffic control, FAA Order 7110.65 is the standard for policy and procedure in the USA. Do other countries use this also?

Is there an 'international standard' for air traffic control? If so, are there any notable differences between that and the service provided by U.S. FAA?


texts: What is the difference between the NTSB's "Aviation Accident Database" and their "Aviation Accident Reports" list?

texts:
I'm trying to understand why there are thousands more records in the "Aviation Accident Database," located here:

https://www.ntsb.gov/_layouts/ntsb.aviation/index.aspx

than there are in the "Aviation Accident Reports" list, located here:

https://www.ntsb.gov/investigations/AccidentReports/Pages/aviation.aspx

For example, in 1991 there are 2,462 records in the accidents database and only 8 records in the accident reports list. What determines whether or not an accident ends up in the list of reports? What is the difference between these two data sets?


texts:
On condition that the pilot reports to ATC, an aircraft's TCAS sees a drone in the vicinity.

How can the pilot be sure that it was a drone on TCAS? What kind of symbol is shown on TCAS that can be identified as a drone? Or is it just a primary radar target pick up by TCAS?


texts: Why there so many pitch control surfaces on the Piaggio P180 Avanti?

texts:
Picture source.

I have seen that there is kind of sonic aircraft like B-1B Lancer that used elevator and canard or fins at the same time for pitch control. That quite understandable because it is fighter jet that required high precision control. There are another airplane that used canard but not elevator, like Tupelov Tu-144. But this Piaggio P180 Avanti is quite strange for me. It is equipped with elevator, canard, and also another additional device. I am not sure that propeller airplane needs what needed by the above B-1B Lancer.

Then my question are, what is that device (number 2 in the picture), what is that name, and what is that for? Are device number 2 and number 3 controllable?


texts: Can a completely drained battery be recharged via ground power on an airliner like the B737?

texts:
When accidentally leaving the battery switch or something powered by the hot battery bus on over night, an aircraft's battery could completely discharge. Normal startup, where the battery is switched on first and then external power is connected, would no longer be possible.
Is it possible to somehow connect an external power unit to the aircraft such that the drained battery is being recharged? Or would maintenance have to swap out the battery or charge it in some other way?

Details for the Boeing 737 are below, but answers for other airliners are welcome:
On the Boeing 737 NG, the batteries are charged via their own transformer rectifier units:

Battery Charger Transformer/Rectifier
The purpose of the battery chargers is to restore and maintain the batteries at full
electrical power. The main battery charger is powered through AC ground service
bus 2. The auxiliary battery charger is powered through AC ground service bus 1.

(Boeing 737 NG FCOMv2 6.20.12 - Electrical - System Description - DC Power System)
These ground service buses can be turned on independently of the main aircraft AC buses:

Ground Service
For ground servicing, a ground service switch is on the forward attendant’s panel.
The switch provides ground power directly to the AC ground service busses for
utility outlets, cabin lighting and the battery charger without powering all airplane
electrical busses. The ground service switch is a momentary push button and is
overridden when both AC transfer busses are powered.

(Boeing 737 NG FCOMv2 6.20.2 - Electric - System Description - Electrical Power Generation)
This sounds like the battery chargers could be powered via ground power in ground service mode. It is however not clear to me, if this push button would even work without any battery charge left.


texts: What is the difference between the ILS Critical Area and the ILS Sensitive Area?

texts:
What's the difference between the ILS Critical Area vs ILS Sensitive Area?

I'm getting multiple conflicting opinions online.

e.g. I can't decipher from this set of definitions how exactly they differ:

  The ILS critical area is an area of defined dimensions about the
  localizer and glide path antennas where vehicles, including aircraft,
  are excluded during all ILS operations. The critical area is protected
  because the presence of vehicles and/or aircraft inside its boundaries
  will cause unacceptable disturbance to the ILS signal-in-space

vs

  The ILS sensitive area is an area extending beyond the critical area
  where the parking and/or movement of vehicles, including aircraft, is
  controlled to prevent the possibility of unacceptable interference to
  the ILS signal during ILS operations. The sensitive area is protected
  against interference caused by large moving objects outside the
  critical area but still normally within the airfield boundary.

All I can grok is that the critical area seems some subset of the sensitive area?

Do I take this to mean no vehicles are allowed in critical area but some smaller vehicles may be allowed in the sensitive area?


texts: Does the "follow" instruction give an aircraft clearance to turn onto a taxiway and/or cross a runway?

texts:
Consider this ATC instruction from a ground controller:

  N123, continue down Alpha, turn right at Kilo, hold short of RWY36.

  N456, follow N123.

Does this instruction mean N456 can turn right at Kilo without further ATC instruction?

What about:

  N123, continue down Alpha, turn right at Kilo, cross RWY36.

  N456, follow N123.

Must N456 hold short of RWY36 and await clearance to cross the runway?


texts: Could an inflatable wing be installed on a Silent glider aircraft?

texts: Would it be technically feasible to install the Pneumagic inflatable wing on the Silent glider?


texts: What are the reasons for the particular range of VHF and UHF frequencies?

texts:
Generally, VHF frequency range is 30~300MHz and UHF is 300~3,000MHz. (according to Wikipedia). However, in ATC, VHF frequency range is 117.975-137MHz and UHF is 225MHz-400MHz.

Why is there a difference? And what are the reasons for these differences?


texts: Should I log flights on separate lines if I park the plane between legs to different airports?

texts:
I flew one leg of a cross country, landed, parked, and turned off my engine. I flew the same plane home an hour later.
Are these two separate flights and should be logged as such, or can they be logged together on one line?
Is there any rule that states how it should be logged?


texts: How can I decode Lycoming engine number?

texts:
How can I decode Lycoming engine number suffices?
What does D3G mean in o-320-D3G or D2A in o-320-D2A?
Is there any chart or tabel for decode suffixes?


texts: What are the considerations to make when altering logbook entries?

texts:
As I move through my flying experience, the possibilities for logging time change.

Before I was rated, my time with an instructor is logged as dual only.  Most of these entries were made by various CFI's.
After being rated, FBO checkouts and flight reviews were logged as PIC and dual. These entries were often made by myself and signed by the CFI.
When receiving instruction for endorsements (tailwheel, high performance, complex), entries were usually made by the CFI.  It appears that most of the time, the instructors making the entries favored the idea that until I had the endorsements, they would leave the PIC column blank and log only dual received.

The answers to This Question lead me to believe that I could indeed have logged this as both dual and PIC, since I was rated for the category and class for which I was flying.

Here is the question:  What consideration should be given before I go back and add PIC to the flights which were filled in by someone else?  Should I leave it alone or claim the time as PIC since I was both "sole manipulator" and rated in that category and class.


texts:
If a plane lands vertically in a strong headwind, what will the pilot do to exit the runway?
If he increases the speed, wouldn't that be dangerous (I mean he will fly again)?


texts: Is it possible to use variable wing geometry on a fifth generation stealth fighter?

texts: Is there any effect on the stealth features due to variable wing geometry? If not, why have such aircraft not been designed till now? Please explain the limitations using any structural principles if possible.


texts: What is the rescue arrow decal on a military jet pointing to?

texts:
I've noticed that a lot of military jets often have an arrow decal with the wording "RESCUE" pointing to a rectangle of some sort. I tried looking around for information about it but I could not find anything. What is the purpose of that rectangle the arrow points to?

The other decals seem to be much clearer: e.g. the red triangles are usually ejection seat warning labels and jet intake danger labels.

My own guess is that it is a button/switch device to trigger explosive bolts on the canopy or another mechanism. If so, what does it look like and how does it function? A close-up and a detailed example would be useful.


texts: Is it possible to access the baggage compartment in flight?

texts:
In this incident the cabin crew entered baggage compartment to find and secure a smoking suitcase. But that was in ATR-72 which has the baggage compartments on the main deck behind cockpit and aft of cabin and passage between cockpit and cabin goes through the (larger) forward compartment.

In this incident it was clearly an advantage to be able to get to the cargo. Would it also be possible in some larger planes? Is there any regulation or guideline explaining why it should or shouldn't be possible?


texts:
For a group project in college, it was required to find the data of some randomly asigned aircraft. My group received the Boeing 727-200C, of which only one was produced. Due to this, no one in my group can find any data on this aircraft, only on the 727-200 Basic or Advanced types.

Mainly we have to look for dimensions, weight, in flight performance (cruising altitude and speed, endurance and range), take off and landing distances and which engine it used.

Where should I look for data? If anyone has this data available, could you share it?


texts:
I am trying to draw the V-n Diagram for a small aircraft I built, but I am stuck in the gust envelope part. I know how it is supposed to look. However, I am having a hard time calculating it. I would like to know (1) why it's composed of four lines; and (2) how to find the slope of each line. So far, I have these three equations:

Also, (3) why do these equations describe the gust envelope, and (4) what each variable in the equations stands for?


texts: What are the communication procedures for flying from one Class D airspace directly into another Class D airspace?

texts: What is the communication procedure for descending through Class D airspace to land at a different controlled airport in a separate class D airspace that is directly next to it, such as Long Beach (KLGB) and Los Alamitos (KSLI)?


texts:
Yesterday I flew back from Tokyo down south against great head wind around 150kt at 34000’, the original flight plan was to cruise at FL240 for a while then climb up, but the captain decided to get up early, which resulted in a longer cruising time.

It became a bit confusing to me in this case,
One, The higher you go the stronger the winds, at the same time the fuel consumption is more efficient, but at what point do you say the wind factors wins over the fuel factors, ex. Take us longer to get to the destination resulting in more fuel burn.

And what are some rule of thumbs to help me develop a decison wether to cruise high or low in terms of fuel saving.

I found a wind altitude trade off in my A321 FCOM, but not too sure if the chart fits my situation, and I’m almost sure the captain didn’t take out the chart to form his decision.

Thank you for your answers on advances. Any input is appreciated.
Best regards,


texts: What are these "F,S,O" characteristic speeds?

texts: I am leaning for an avionics exam and I encountered a question asking for the meaning of F, S and O . They appear to be "Characteristic speeds", which are calculated by the flight management system (FMS):


texts: Why is the DC10/MD11/TriStar vertical stabilizer noticeably smaller than other contemporary aircraft?

texts:
Why is it that these planes had vertical stabilisers that were noticeably smaller in proportion the aircraft itself to other aircraft? I understand that they had the engines mounted on the tail but couldn't the surfaces have been made larger? Doesn't this make it more difficult to control during flight as the surface is way smaller? Maybe is had some other mechanism in the engine that could compensate for the smaller area of the vertical fin?
I've added some images of the DC10, the TriStar, Boeing 767 and A310 which are aircraft that are sort of comparable in era and age and the most interesting one is the TriStar which so small:


texts: How to best navigate around and land at KPAO (Palo Alto, CA)?

texts: Flying VFR into KPAO from the South for the first time in a Cherokee. Any advice on the best way to navigate KSJC and the SFO Bravo?  Thanks.


texts: Where does the flat plate theory in this paper come from?

texts:
The aerodynamic model cited in this paper (pdf) as "flat plate theory" was a good first-order approximation of the aerodynamics of a perching glider. I immediately saw the similarity with the Newtonian theory that works well in hypersonics, but it is only a similarity, not the same.

Around the internet I found these other two articles: (1) and (2), which make reference to this flat plate theory in the context of wind turbines.

My questions are:

Where does this flat plate theory come from?
In what textbook or article or other bibliographic reference can I find its derivation?

Edit:

Here is another article that cites this flat plate theory, now in the context of aircraft flight dynamics. This one makes reference to (1).

Here is yet another one in the context of wind turbines.


texts:
On the A320 family there are circuit breaker panels in the cabin between the exits. On the 2000VU panel there is a "camera" circuit breaker (C5 position):

Top: Source -- Bottom: A320 CCOM p165 -- Right: A320 CCOM p166

Which camera is it related to?


texts: Do you have to worry about airborne disease on an international air flight?

texts:
Flu? Pneumonia? Anthrax? smallpox? Do you have to worry about them or there are designs in place to prevent them? Like some sort of sophisticated ventilation system?

Models to work with: Most common ones: Boeing 737, Airbus A320


texts: Why are airspeed gauges labeled above Vne?

texts:
Examples:

Cessna 150L Vne = 141 knots (162 MPH), gauge labeled to 170 knots. It looks like there's room to extend the scale to 180.
Cessna 152 Vne = 149 KIAS, gauge labeled to 170.
Cessna 172R Vne = 163 KIAS, gauge to 200

Is the extra range deliberate? Is there a use for it?

Is this specific to Cessna models? I browsed instrument panel photos and didn't find a non-Cessna example. For most aircraft, it seems the range extends past Vne only to the next convenient round number.


texts: What are the differences between foward air controllers in US military?

texts:
US Military has forward air controllers that join the forces on the front line and help them communicate with aircraft on the battelfield.

I found several Wikipedia articles describing such position, but can't understand what are the differences between them.

https://en.wikipedia.org/wiki/Tactical_Air_Control_Party

https://en.wikipedia.org/wiki/Forward_air_control

https://en.wikipedia.org/wiki/Joint_terminal_attack_controller

https://en.wikipedia.org/wiki/United_States_Air_Force_Combat_Control_Team

https://en.wikipedia.org/wiki/United_States_Air_Force_Tactical_Air_Control_Party


texts: How does flying with flaps differ from flying with airbrakes?

texts:
I've got a private pilot license and learned on a Scheibe Falke SF25. For the last year however I've only been flying a C42 Ultralight.

I find flying the UL way easier for one particular reason: it has flaps where the Falke has just airbrakes.

I don't know how many hundred landings on the Falke I have done, still I have never felt comfortable. The reason is the airbrake. For some reason it scares me. With the UL I set the speed, lower the flaps and if I'm too far away I can add a little power. The flaps lower the stall speed and make the plane slower.

The airbrakes also make the plane slower, however they increase the stall speed. I see how (especially flight instructors) pull the air brake to the maximum and then do their approach. If I'm too far away with the Falke, I have to retract the air brakes. This affects the plane very directly, especially compared to adding a little power on the UL.

My questions are:

How to correctly land a plane with airbrakes? Full out or just a bit? Do you leave them in one position or do you vary during approach?
How much do they really affect stall speed?


texts: Which organisation deals with Aviation Law - IATA or ICAO?

texts: Both Organisations are involved in Aviation Regulation. But which of them deals with Law? Are directives given by both equally applicable to all aircraft & airline operators?


texts: Who is responsible for providing ATC in a TMA?

texts:
I know that TWR, APP, and ACC control ATZ, CTR, and en-route; but I'm not sure about the control service which is responsible for monitoring TMA (APP or ACC?!).

Could you please clear the case (preferably by a European reference)?


texts: What part of an aircraft design process is governed by mathematics?

texts:
I am well aquainted with the six steps of the engineering process, but what is the six steps of design specifically for aircrafts (if there is one)?
I'm very mathematical, so I would appreciate it if you could include equations that are necessary for each step.
Also, does anyone have a CFD that they would recommend? I'm building models in AutoCad, and am currently working with a CFD called Anasys.

Right now, I understand how the different components of a plane affect its flight, but I am really more interested in understanding how to design a plane using math.  I do a lot of work with rockets, which is governed by a pretty good set of written equations, but I was hoping I could do similar in the field of airplanes.


texts: Is it possible to land a 737 on an aircraft carrier?

texts: I have seen a flight simulator (X-Plane 11) video of landing a 737 on an aircraft carrier (and stopped). Is it possible to land a 737 in real life? What is the biggest aircraft that it is possible to land on an aircraft carrier?


texts: Why does Martin-Baker use a Gloster Meteor as a testbed for ejection seats?

texts:
Martin-Baker uses a Gloster Meteor for testing ejection seats, according to their website.

While it's a stylish plane, and a true delight that there are still airworthy fuselages of this plane left, it seems strange to use such an old aircraft as a testbed.

The Gloster Meteor was one of the very first turbine engine planes, made during the Second World War. In terms of electronics and structure it's a far cry from a modern fighter.

How does this make sense? Wouldn't it be better to test ejection seats in the aircraft they will be used in, with the correct structure and canopy?


texts: What plane is this, looks a lot like a BAe-146-100 or an Avro 146-RJ100, however with only 2 engines?

texts:
I saw it and took a picture. It is flying out of Phoenix Sky Harbor International Airport. It landed at about 5:27 if that matters. It is a green tail livery that extends downward. The wings are above it like on a C172 however the engines are straight under the wings. The engines are fan engines, not props. It looks like the 146-RJ100 with only 2 engines total though.

Thanks for your help!


texts: How can two planes be on the same taxiway facing opposite to each other?

texts:
Curious to know how two planes can be on the same taxiway facing opposite to each other at the same time? Please have a look at the satellite view of the following coordinates in Google Maps:

(-27.369843, 153.126482)


texts: Is the 737-800 circular PFD for AOA or RA?

texts: So, I have seen some people on the Internet showing the 738's PFD circular gauge for RA, but others show that the gauge is used for AOA(angle of attack). Which one is true? Is there a switch to change the circular PFD gauge between RA and AOA?


texts: What are the SOPs following an overweight landing?

texts:
Modern commercial aircraft are certified to be able to land at any weight providing that the runway is long enough.  The "overweight landing" QRH procedures for the 734 and A320 are correspondingly quite short, referencing mainly the approach reference and target speeds and adjusting for wet/contaminated surfaces.

This video (which by the way, deserves repeated watching - there is just so much to look at, e.g. the vortexes high above the wings and from the flap outboard trailing edges) unfortunately is clipped from shortly after the emergency response crews arrive until the aircraft vacates under its own power.

This made me curious as to how the decision to taxi clear is made.  Are there QRH/SOPs for this, either the operator or the airport?

My guess is that the fire fighters will check the bogies for any sign of fire and, coupled with the crew checking EICAS and the wheel and tyre temperatures and pressures, make a joint agreement that it is safe to vacate.

Following vacating, would the QRH/SOP be to stop when clear and allow extra time for cooling (which could be a long time) or taxi to the stand?

Wouldn't taxiing to the stand increase the risk of a fire starting even if there was none after it had stopped on the runway?

And that video, oh, watch it again.


texts: What is the angle of attack of horizontal stabilizer?

texts:
It 'appears' that in most flights the horizontal stabilizer is set for positive angle of attack.

So does this produce an 'up force' (lifting force) on tail thus making the aircraft nose-heavy?

Or does the horizontal stablizer presents itself to the relative air at a different angle of attack than the wing does (which creates down force on tail)?


texts: Are the CAA and FAA Class 1 medical certificates equivalent?

texts:
Is the CAA medical class 1 certificate equivalent to the FAA class 1 medical certificate? How so?

Or does one have to convert to the FAA license in order to achieve the medical certificate?


texts: How does a full fuselage and structure inspection happen in practice ? (for modern Civil airliners)

texts:
What are the intervals at which a full structure inspection take place ?

How much time does a test commonly take for narrow and wide body aircraft ?

Is every part in the structure manually inspected by the operator in level C Check or some parts only depending on the Structure repair manual (SRM) of the aircraft?


texts: How should night time be determined and logged in a fast westbound plane?

texts:
You take off from KFLL (Ft Lauderdale, FL) an hour before sunset in a B737. You're heading to KSEA (Seattle, WA).

4:35PM EST plus 6 hours 34 minutes is 11:09PM EST, or 8:09PM PST.  Seattle sunset was 4:22PM PST.

Since the flight went west quickly it delayed sunset. Since it went north in the winter it hastened sunset.

So how does the flight crew split their day and night flying portions?

Record UTC when the PIC declares it to be night, split accordingly
A computer just tells them the answer
The flight crew already have ATP ratings, they don't care for detailed logging anymore
Something else

All of my flying has been roughly north/south at C172 speeds, so it hasn't really mattered more than the rounding error of recording in 0.1hr increments.


texts: What is the shape of the power required curve?

texts:
I understand that when flying level, some power is required to maintain altitude, this power amount being:

Normally larger when the speed is larger, this is flying on the forward side of the required power curve.
But below the minimum required power, this amount of power needed to maintain altitude goes down when speed increases. This is flying the backside of the curve.

This can be represented like this:

Being on the backside of the curve means flying in an area of strong instability, possibly reaching the stall point if not managed correctly.

Question: What is the shape of this power required curve for a small GA airplane, and for a large commercial airplane?

I mean is the backside a small portion where it is unlikely to be without obvious pilot mistake? (left hand side below) or is it a large area where it is easy to fall? (right hand side)


texts: How (or where) do I find an airfoil optimized for low reynolds numbers (100,000~150,000)?

texts: Looking to build a RC plane. Because the span is going to be small and the speed relatively low, I estimate the R-number to be around 100,000. Is there an airfoil optimized for that range of Reynold's Number?


texts: Can all airborne aircraft be stored at their origin or destination airport?

texts:
With the progressing outbreak of the Corona Virus the IATA has recently changed its predictions about the losses to be suffered by the aviation industry

The losses originate from the reduced number of passengers and the subsequent grounding of aircraft for which there are no passengers.

The question is, can all the aircraft in the air be grounded at either their origin or destination airport. If not, where else can they be stored?


texts: Is there a specific formula or way to calculate flex temperature for an Airbus A320?

texts: I have hear of RTOW charts but I haven't seen any calculations with the runway length or slope. What is the formula or equation to finding flex temperature and V-Speeds?


texts: As a commercial pilot, can I fly my spouse for her work?

texts:
So I hold a commercial license and have a 2nd class medical.  My wife is an engineer and a product she works on needs to be altitude tested (unrelated to aviation). She was suggesting that we could rent the plane from the flying club I am a member of and she could submit the receipt and get reimbursed for the flight cost. If she wasn't my spouse and was a friend asking me to rent a plane and give her the bill I'm pretty sure this is pretty clearly not OK.

We talked about doing a "pro-rata share" but wasn't sure how that's defined cause... it's my wife - shared finances and all that.  Any experts have any feedback on whether or not we're okay to do this?  Or if we really want to do it do we just eat the cost of the flight ourselves?

EDIT: Clarifying based on comments - This is USA (CPL) and my wife and/or company wouldn't be on the bill. It would be my name because it's a flying club and they would only rent the plane to me.  So it would get charged to a credit card in my name (joint account with my wife) and she'd turn around and get it reimbursed.  I agree, I'm not "holding out" in my opinion... but just trying to make sure I keep things above board.


texts: How tough/easy is to crack a 787 type rating course? Is a wide body aircraft difficult to fly especially when you are transitioning from 737? Any tips/suggestions would be much appreciated.


texts: For any given modern turbofan engine, does bypass ratio stay approximately constant during a typical flight?

texts:
Bypass ratio is the quotient of mass flow rate through the bypass duct over mass flow rate through the engine core. Does it stay constant during the typical flight of an airliner?

If it does not stay virtually constant, what are the driving factors?


texts: I have really intense ear pain during descent in commercial flights. Would it be better or worse if I was flying a small non-pressurized plane?

texts:
Usually — but not always — after descending in a commercial jet airliner, my ears really hurt for several days, accompanied by minor hearing loss.

Nonetheless, I am still in love with aviation. I am thinking of starting my lessons to become an ultralight (UL) pilot. Could flying a non-pressurized plane actually make these problems worse?


texts: Why is autolanding ILS a thing, but not autotakeoffing ITS?

texts:
In this answer to the question of why zero-visibility landings are legal and routine but not zero-visibility takeoffs, the poster makes the following point:

When an aircraft lands in near zero visibility, it is a fully automated process that is actually done without input from the pilot. The pilots are only needed to taxi off the runway and park the aircraft. It is called "Autoland" and many of today's aircraft have it.
As of today no manufacturer has designed an aircraft with "Auto Takeoff" but I suppose it is not impossible.

(Emphasis added.)
Which seems odd, given that autolanding with an ILS is a mature technique using mature technology, and autotakeoffing with an ITS (instrument takeoff system) wouldn’t need much more on top of that (just some additional antennae on the aircraft’s tail and a couple new routines for the autopilot) - it’d mostly be pretty much an ILS running in reverse, something like this:

What’s the dealbreaker for an autotakeoff-supporting instrument takeoff system?


texts: Delta fleet plans - all Airbus? (and Bombardier)

texts:
With Delta ordering A321neos and C-Series not 737 Max 10s, A339s, A359s instead of 789's, might Delta be on their way to an all-Airbus fleet? Or going away from Boeing?
Was the 737 Max vs A321neo deal really a "P&W over CFM" deal? Or was it just "Airbus > Boeing" etc. in disguise?
Would Delta ever actually order (and take delivery of) any 787's in the future? (Maybe in like 10, 20 years or so)


texts:
What will the magnetic compass which has an Easterly deviation of 10 read when the true heading is North
Will it read 350W or 10E?
I understand that the 10E East variation means that the underlying magnet is swung 10 deg clockwise instead of pointing to true North. So it is now pointing to 10E. But I guess since the readings are done from opposite side of the compass for the end user, the reading shown will be 350W.
Help!
edit : The question is different from what is answered at How do I convert true heading to magnetic heading or the other way around? --  My question is mainly regarding how to visualize the same. - John's answer below is perfect.


texts: If I am cleared to land a couple of miles on final, may I use the entire runway to the departure end, or do I have to comply with "taxi instructions" the tower controller might give me like "turn right at taxiway foxtrot," while I am still concentrating on safely completing the landing? If he gives such a clearance, and I don't acknowledge for safety reasons, do I still have to comply? If I do acknowledge and do not comply, have I committed a clearance deviation? It's great to "help the guy behind me on final" but is this type of clearance even supposed to be given? If I slide off into the grass trying to comply with a clearance that has no relation to my landing calculations, who goofed up?


texts:
I've seen many articles that compares the risk of skydiving with other sports or activities like cycling or driving. However, they are very ambiguous in terms of how the risk was calculated (number of jumps, number of km driven, etc). Here is an example:

Image taken from here.

So, how much is the risk of a single jump?
How does that compares with a common activity like driving a car?