texts: What is the maximum interception angle for ILS when on radar vectoring?

texts:
Some time ago when I was designing the approach radar module for the ATC simulator for HCAA, the spec was very clear that the limit had to be placed at 45 degrees. So I took it for granted and I didn't make any research of my own.

But very recently I had a discussion that made me wondering and I couldn't find any online documentation. I found Lnafziger's answer suggesting that

  Controllers may issue a heading or a course direct to a fix between the IF and FAF at intercept angles not greater than 30 degrees for both conventional and RNAV instrument approaches

So I guess this is it for FAA airspace. But I would like to know if there are any EASA regulations or ICAO recommendations that impose 45 degrees in Europe.


texts: Why are there some airports not charted as service-available when FBO provides fuel?

texts:
On FAA's Aeronautical Chart User's Guide - VFR Charts.

It says the tick-mark charted airports provide fuel service. However, at Airport KSIY and 1O5,

There are FBOs at both airports. e.g at Airport 1O5

Is there any reason why these service-available airports not charted as ticked. Do they need to satisfy any FAA requirements before charted?


texts: How can the A320 receive 3 DME signals if it has only 2 DME receivers?

texts:
How can the A320 receive simultaneously 3 DME signals (VOR1 + VOR2 + ILS) if it has only 2 DME receivers (and antennas)?
Does it multiplex them in some way? If yes, does it mean if one DME receiver fails I can still get simultaneously 3 DME values?
There is a video that shows 3 DMEs tuned simultaneously: Airbus Cockpit Views | Episode #6 | PFD View Landing STN RWY22

VOR1 (DME1) being automatically re-tuned, followed shortly by VOR2 (DME2), plus the already tuned ILS


texts: Does transition to SBAS or GBAS navigation require alignment of the intermediate segment with final segment?

texts:
I am studying how the Satellite Based Augmentation System (SBAS)  or the Ground Based Augmentation System (GBAS) affect the Instrument Approach Procedures, and I noticed that in ICAO's Aircraft Operations manual (8168, Volume II) it states:

  Part III, Section 3, Chapter 5, 5.3.1: "General. In the intermediate approach segment any sensor can be used; however, the transition to the SBAS navigation shall be made 3.7 km (2.0 NM) prior to the FAF.

  Part III, Section 3, Chapter 5, 5.3.2: Alignment. The intermediate approach segment of an SBAS procedure shall be aligned with the final
  approach segment.

  Part III, Section 3, Chapter 6, 6.3.2: "The intermediate approach segment of a GBAS procedure shall be aligned with the final approach course."

Does the above quotes imply that the intermediate segment must be aligned with the final segment 2.0NM prior to the FAF, in order for the aircraft to be able to switch to SBAS navigation?

In addition, concerning both SBAS and GBAS, I would like to make sure if the rule concerning the alignment of the intermediate segment with the final segment implies that the whole segment (each leg of the intermediate segment) has to be aligned with the final, rather than only the last leg.

Could someone point me in the right direction?


texts: Are there any NACA airfoils that resemble the X-29's wing?

texts:
As a part of my project, I am trying to perform structural and aerodynamic analysis of a forward swept wing on an aircraft, specifically the Grumman X-29 (pictured below).

I am assuming that information on the airfoil and wing of the X-29 is proprietary information. So, are there any open source airfoils and wing dimensions (NACA or otherwise) that closely resemble the X-29 wing?


texts: What are the difficulties and dangers faced by low flying aircraft?

texts: Aircraft could fly low for various reasons,  Common reasons for low flight are sightseeing, photography, crop dusting, staying below Bravo/Charlie airspaces, flybys, and "just cause I felt like it".  What are the  difficulties and dangers faced by such aircraft?


texts:
It seems that flying a plane in a slip can make passengers uncomfortable.

What is it about that configuration that is unsettling?


texts: Why is the CFM56 produced with two different thrust reverse options?

texts:
According to Wikipedia, the CFM56 could support several reverse thrust options, and it appears that it has actually been built with 2:

Boeing seems to prefer the cascade type
Airbus seems to prefer the pivoting door type

Is this a simple case of catering to customer preferences, or is there a more in-depth reason for having multiple reverse thrust options?


texts:
Is lower wing loading safer?

Looking at the ultralight specs in Canada, they call for a max wing loading of 12psf.  In fact, amateur built aircraft in Canada cannot have a wing loading over 20psf,I'm told.

While in the US, we see aircraft like Rutan's Boomerang at about 42psf.

Seems many GA aircraft seem to be stuck at 14-17psf range

With VG's or slats and flaperons  (full length flaps) and then slatted
(junkers flap(?)), Zenith is getting a nice cl of about 3.0, about double a typical ultralight

Why not higher wing loading?  This would lead to smaller wings, better aspect ratios, less drag, which means smaller engines, which means more affordable GA aircraft.

In fact, Rutan's motorglider (solitaire(?)), had a top speed of about 200(?) mph, with just a 4 cycle 18hp industrial engine ( rated for continuous duty), the kind you can buy at a big box store for $500.

I understand M. Coulumban, the designer of the cri-cri, just switched to low cost industrial honda engines as well.

On a saturday morning 1,000 mile cross-country trip ( pretty routine for the long-eze crowd)and have engine problems? No problem. Just go to a big box store and buy a new one and install it in an hour. Might as well make it an inline twin for that low of an engine price. Rutan's twin Defiant could take off from either engine alone, or both.  Seem's pretty foolproof to me.

Seems like pretty good economics for GA aircraft in my mind.

So..... why limit ultralights to 12psf.  I assume lower wing loading means it's safer.  Lot's of wing means it's harder to stall.

Is this correct?


texts: Does the wake from horizontal stabilizers merge with the wing wake?

texts:
There is already a long series of questions about the downwash and tip vortexes with nice images, but I'm going to add another one...

Large airliners (A380, B747-8) have horizontal stabilizers competing with small Boeing wings, and definitely larger than business jet wings.

Source

How does the tail wake look like when the horizontal stabilizers produce significant lift? Does it merge with the wake from the wing or is there a second wake above the first one?

Edit: I've found this image:

Source

Which shows the tail vortexes below the wing vortexes, and apparently larger than them.


texts: Can I file a VFR flight plan for a training flight?

texts: Let's say you are going to do some maneuvers in a practice area, make a few touch and go landings at a non-towered airport, then return to your home airport...is it possible to file a VFR flight plan for this?


texts: TCAS II - bottom omni-directional antenna

texts:
I know that the TCAS II system has a lower antenna which can be either omnidirectional or directional.
How does the functionality of the system change? If the antenna is omni then I think / assume that it cannot know the bearing of an intruding aircraft and therefore can not provide data to position it on a display. Is it only used for transmitting interrogation and/or receiving other data?

Thanks,

Ori


texts: What are the rules for flying drones in National Recreation Areas?

texts: National Recreation Areas allow powerboats on lakes and roads for vehicles, so can drones fly in this area? Can model aircraft fly in this area? Can model boats be used on the lakes or rivers? Can rafts be used in the rivers?


texts: How do you write 'to', 'then', or 'via' in IFR clearances shorthand symbols?

texts:
Although there are NO restrictions about the usage of shorthand symbols, still it would be useful when I fly with another person together, so I studied those symbols and got some doubt points.

If someone wants to write 'N123 is cleared to AAA airport'
I assume it would be 'N 123 C AAA A', so shall I exclude 'to' in this sentence?

How about 'via B departure then as filed'?
It seems that I can write 'via' as 'VIA', But I can't replace 'then' with '>' or '→', since each of those means 'before' and 'cruise'.

I referred to the site below, about symbols :
https://nova.aero/repository/IFR/IFR%20Clearance%20Shorthand%20Symbols.pdf


texts: How would a Flying Fortress behave if it lost its empennage mid-flight?

texts:
The 1990's movie "Memphis Belle" depicts a Flying Fortress having the whole tail cut by a fighter impact on the rear part of fuselage, as a razor or chainsaw will do, the bomber airplane enters a flat descent with all 4 engines operating.

Is this type of accident possible? How would such a bomber behave with the empennage cut? Is there any way or chance to survive such an accident?


texts: Where can find Service Ceiling of an aircraft?

texts:
I would like to figure out the service ceiling for Cessna 172N and I couldn't find it anywhere in the POH.

Where can I find it? In POH or somewhere else? If in POH, please post a snapshot of it.


texts: how to know about designed airways above my house

texts:
Newbie here.
I hear quite a lot airplanes and helicopters and all kind of weird flying things above my head, at least one every 2 or 3 minutes, so I started tracking them with ADS-B.
There's a commercial airport in the region (MXP), not extremely close, but it seems that my house sits on some kind of airway (? not sure about the correct word) because everything leaving and approaching that airport to/from east just passes over my head making a lot of noise and I do not notice the same thing when driving nearby.
So my question is: is there a publicly available information about these routes? Are they static? I tried to check skyvector but I can't understand those.
Is there some kind of altitude limitation flights must comply? Just for fun, I'd like to compare those with ADS-B received data.

Edit: screenshot attached, on the left there's the airport, on the right two planes and an helicopter that just passed above my head.
Highlighted one is almost above my house.


texts: How could the Helios 522 passengers have survived so long without oxygen?

texts:
I've noticed some strange inconsistencies regarding the documentation of Helios Airways Flight 522.

So first:

  Autopsies on the crash victims showed that all were alive at the time of impact

But then:

  The emergency oxygen supply in the passenger cabin of this model of Boeing 737 is provided by chemical generators that provide enough oxygen, through breathing masks, to sustain consciousness for about 12 minutes

So, the oxygen masks in the passenger cabin automatically deployed at 18,000 feet, probably around 09:20. The aircraft did not impact until 12:04. 2 hours, 44 minutes later. Obviously the oxygen masks didn't keep them alive for that long, so:

How could they have survived so long?


texts: What does scheduled departure time exactly mean?

texts:
I am trying to understand the (sometimes subtle) differences between various terminologies concerning flight schedules. What I find difficult to understand is how exactly the scheduled departure time is defined. My initial thought was that it refers to the time where the aircraft leaves the gate, after the boarding of passengers. However, I noticed that this definition is closer to the term "Target Off - Block Time".
ICAO ATFM TERMINOLOGY AND COMMUNICATIONS, page 7:

Target Off - Block Time:
The time that an aircraft Operator or Ground
handler estimates that an aircraft will be
ready to startup/pushback immediately upon
reception of clearance from the tower.

Could someone clarify this issue?


texts: Is locking the cockpit door from inside is a normal procedure when one pilot leaves?

texts:
When a pilot leaves the cockpit to go to the toilet should the second pilot lock the door?

For me it's mandatory in case of the other pilot is taking in hostage and is forced to tap the code.

So can the pilot still in the cockpit can have locked the door and then lose consciousness?

Imagine the pilot goes to toilet and a problem occurs, the plane start to stall for example, and he can't reach the cockpit leaving the other alone to manage the situation.

For me the only situation is 3 pilots or never let him goes outside in small trip.


texts: Is wing sweep needed on supersonic aircraft?

texts: Area rule states that bodies with the same crossectional area distribution have the same drag. Does that mean I could use a straight wing on mach 1.2 aircraft with performance as high as sweep winged plane as long as they have the same area distribution?


texts: Can you jump out of a crashing plane just before impact to improve your chance of surviving?

texts:
Let's say a plane is going to crash and all people on board know this.

Why can't they jump from the aircraft when the plane is near the ground?
They would have higher chances of surviving, right?


texts: What is the difference between buffeting and fluttering?

texts: As I understand, both are dynamic effects of aeroelasticity - however, what is the exact difference between buffeting and flutter?


texts: Has someone with no experience at all ever taken off in a plane? Could they?

texts:
I was watching Mystery Science Theater 3000 and their showing of 1970 TV movie/pilot San Fransisco International.  One of the plots in the movie involves a twelve (or so) year old boy, who, alarmed about his parents' imminent separation, wanders across the tarmac, hops into the cockpit of an Aircoupe, and flees his mother by starting the plane and taking off before anyone quite knows what's happening.  After he unsteadily flies it a bit (the best part of the movie is some stunt pilot making the Aircoupe swerve through the air like a drunken eagle), Bonanza's Adam Cartwright talks him through a safe landing.

Plenty of questions have been asked about the possibility of planes being landed by someone with no experience at all, and, of course, talk-down landings are a real thing, even if they're rarely done by anyone with zero experience.  But I'm curious about the first part, where the kid turns a key, taxis away, and is up into the California sky without even having played Microsoft Flight Simulator.

Naturally, a civilian getting into a cockpit at SFO without being stopped seems patently absurd in the security-conscious present, but times have changed.  Has anything even similar to this ever happened?  And if not (if this doesn't over-broaden my question) could a layman get a plane, single-engine or otherwise, into the air without any experience?


texts: Turbofan engine 2 spool - Turbine drives the compressor or Starter drives the compressor

texts:
I have read somewhere regarding turbofan engine 2 spool that says

"LP or HP turbine will drive the LP or HP compressor"
"During engine starting, the starter will drive the HP compressor via the gearbox"

So I'm confused on whether the turbine or starter drives the compressor. Is it only during starting the starter will drive the HP compressor and after that turbine will take over?

Thanks


texts: Is anti-icing a small area of the windscreen (hot-plates) adequate for the full flight or only an interim solution?

texts:
I asked this question about what "the thing on the windscreen of some Piper aircraft is". It came out that it is used as small anti-icing.

The user Jules asked following in a comment of an answer:

  Is de-icing this small an area generally beneficial for longer flights, or is it "just good enough" for a landing at the nearest airport if the ice buildup is starting to seem hazardous? (Asking as a non-pilot)

I also think it's a good question, but unfortunately the author of the answer didn't answer.

Thank you!


texts: What makes the "howling" sound from airliners?

texts:
Quite often I hear a kind of "howling" sound coming from airliners when I'm at a general aviation airport, which is located at 13nm from an international airport.
Normally these airliners overfly the general aviation VOR at around 10.000ft and then keep descending while flying towards the international airport.
Does anyone have any ideas about what could be the cause of such a weird noise? Could it be associated with any aerodynamic effect?


texts: Do 121.5 MHz ELTs have to be replaced with 406 MHz models?

texts:
There has been a lot discussion about replacing 121.5 MHz emergency locator transmitters (ELTs) with 406 MHz ELTs, since 121.5 MHz ELTs are no longer monitored by satellite.

Are private planes required to have 406 MHz ELTs for operation? Is there a deadline for conversion? Since this is a country-by-country regulation, I am interested in

Canada
U.S.
Mexico
Bahamas
Europe
Australia
(other countries, if information is available.)


texts: What is the purpose of the black and white stickers on test aircraft?

texts:
I want to ask what is the purpose of black and white stickers used on test aircraft.

The following is a picture:

I have seen variations of such stickers. Does anyone know what is reason for their use ?


texts: Why is the phrase “infinite energy” used by this (alleged) ATSB investigator?

texts:
In the Air Crash Investigation episode, “Titanic In The Sky”, a Quantas Airbus A380 suffers an uncontained engine failure which partially cripples the plane. In the investigation part of the episode, an “ATSB Investigator” says that:

  […] the fragments [from the rupture of the fanblade] are released with an infinite energy, which means that there's nothing that can stop the engine pieces¹.

Did he forget to add virtually, or is the ATSB just not very accurate when they talk about these incidents on TV? Or is this terminology actually used in aviation contexts?

If you accelerate an engine blade to have infinite energy, hydraulic failures would be the least of your worries².

It should be noted that I cannot find unlimited or infinite in the preliminary ATSB report.


texts: What is the reason for this route while flying from USA over Cuba?

texts:
I was flying from Canada to Jamaica, and just past Florida the plane turned 90 degrees towards Nassau. It then continued over Cuba. Is this because of the situation between Cuba and the United States? It appears the plane must enter Cuban airspace from international airspace. But I have heard some planes can enter Cuba via corridors from the US. I am confused over this situation.

This was flight TS0373 on 17Jan2016.


texts: What are these lights above the panel in a Blue Angels cockpit?

texts:
I found the following picture on the Blue Angels Facebook page:

What is the purpose of the lights over the pilot's panel? (The two on the top are green)


texts: Advantages of inverted Delta, straight leading edge?

texts: The advantages and features of a Delta wing have been very well described here, but this arrangement of an 'Inverted Delta' differs; also, it would be good knowing more about performance of a Canard foreplane with an ordinary and inverted Delta wing.


texts: Is "passenger loading bridge" a synonym to "contact stand"?

texts:
In a master plan of an international airport, which is already approved by the client, I face some confusion between the terminology of the PLB and the contact stand.

Sometimes they're mentioned just as the same component, not like other locations. I assumed a sort of a conflict in the master plan but I'd like to confirm this please.

Is there any  benchmark like ICAO or IATA that defines such components, e.g., the gate, rotunda, PLB, contact stand, etc.?


texts: Why are the controls of transport category aircraft much heavier than light aircraft?

texts:
Anyone who has transitioned from light GA aircraft to large turbofan airliners will notice the difference: the control column on a large aircraft is much heavier. While still within limits of a healthy adult, it takes a considerably larger force to move the controls.

Why is this? Is this intentional, or just a by-product of the early days mechanical linkages? Airbus has shown that even on airliners, the controls can be made as light as simple joystick. So why can't the controls of a Boeing 747 feel the same as a Cessna 172?


texts: What aerodynamics forces are acting on a jet fighter during slow flight demonstration?

texts:
I have long been contemplating the forces involved in certain maneuvers in an aeroplane and some of those maneuvers begin to break down my understanding of the forces that specifically oppose gravity. Typically this is described as lift and that is how it is explained in ground school, but they did not go over other forces that can be involved keeping a plane in the air (i.e. a non-horizontal component of thrust etc.). They probably didn't go over this as it doesn't apply (significantly) to the type of planes you're one would fly right after basic ground school.

One of those maneuvers I've thought about is a "slow flight" when performed at an air show by a jet where the jet appears to be going slower than their stall speed and at a very high angle of attack. It seems that a portion, if not all of the force keeping the airplane airborne is coming not from the wings in the form of lift but rather the thrust produced by the turbine. (Example:

            )

Is my understanding accurate?
Is there a good, well known reference to aerodynamics that does not gloss over the entire gamut of forces involved during a wide range of flight situations?


texts: How did a Soviet SA-3 missile manage to shoot down the F-117 Nighthawk?

texts: This question is about the F-117A that was shot down in 1999. How did an obsolete missile like the SA-3 shoot down such an advanced aircraft for its time? This question has nothing to do with how aircraft have become more stealthy. It is specific to the 1999 incident. I am just curious as to how an aircraft this stealthy could have been shot down.


texts: Have there been any cases of collision/airprox of small drones with manned aircraft?

texts:
Small civilian mini-drones such as the DJI Phantom or professional surveying drones are becoming increasingly widespread, raising concerns about the potential collision/airprox with manned aircraft (especially GA where flight altitude is typically relatively low).

Have there been actual cases of collision and/or dangerous airprox reported so far? What were the consequences?


texts: Can commercial airliners fly over hurricanes?

texts:
When Patricia was making landfall yesterday I opened up Flight Radar 24 to see if there were any planes flying around or near it.  As I had expected, there were a couple of storm watching planes near the hurricane, but what surprised me is that there were some commercial flights that seemed to be going over portions of the hurricane...

So, I'm curious, can commercial aircraft go high enough to simply fly over a hurricane, assuming they take off and land at airports that are not effected by the storm?  Or perhaps they can only safely fly over the fringes and need to stay away from the eye?

Basically, can airliners fly over hurricanes, and if so can they fly over all of it, or just parts?


texts: Do the drag force (D) and the drag coefficient (Cd) vary with altitude?

texts:
And also how is it related to Reynolds number?

Image source

Edit: Consider two airplanes, one flying at sea level and the other at altitude and both are at the same angle of attack and true airspeed. Will the drag force experienced by both of the airplanes differ? And also what about the coefficient of drag at the same angle of attack and true airspeed?


texts: Wake turbulence: crossing under a final approach path VFR

texts:
Flying VFR around the Bay Area I’ve had two experiences recently that made me a bit nervous, but I haven’t been able to find recommendations that fit the situation.

The first was flying (C172) north along the east bay hills somewhere between OAK and LVK, around 3500’. We saw a 737 descending towards OAK ahead and above us, crossing right to left. 2 or 3 minutes later, long after I’d forgotten about it, I think we crossed the descending wake: we felt a single very sharp bump, hard enough to feel like we’d hit something.

The second time, I was crossing the bay just east of SQL on a northeast heading. ATC pointed out an A380 on final to SFO ahead of us. They passed in front and above us, and I turned to cross their path at 90 degrees, thinking this would be the right strategy for minimizing the risk of being rolled by the vortices. When I later checked the flightradar data, they were about 1000’ above us where our paths crossed. We never felt a bump, though the controller who watched this asked me how the turbulence was, so he evidently thought we were taking a risk.

Of course I know the mantra about wake turbulence is to just avoid it. But in practice, in a situation like this, I might have to divert for 5 minutes or so to try to fly “around” the wake area (e.g., in this case turn SE paralleling the flight path in reverse before turning back on course) and it seemed to me that crossing a wake at 90 degrees seems like a reasonably safe thing to do, a couple of minutes after the plane had crossed (though I couldn’t really judge the vertical separation).

I can’t find anything in faa docs on this situation. They’re all about takeoff and landing. And the bad stories about planes being damaged/destroyed by wakes seem to always involve a near 0 or 180 relative heading (i.e., flying along the vortex line so the two wings see a large force difference).

I’m curious what others think about this.


texts: Advance ratio formula for drone propeller in vertical climb

texts:
According to this wikipedia article. There are two expressions for advance ratio:

For propellers:
$$J = {V_\infty \over nD} \tag{1}$$
For helicopters:

$$\mu = {V_\infty \over \Omega r} \tag{2}$$

We know that: $\Omega = 2\pi n$, so by substitution in (2):

$$\mu = {V_\infty \over {2\pi nr}}= {V_\infty \over \pi n D} = {J \over \pi}$$

So $\mu \neq J$

My question:
In case of a helicopter in a vertical climb (no forward velocity) with constant velocity $\vec v = (0, 0, u_z)$, which expression should I use for advance ratio? $J$ or $\mu$?


texts: Is there an engine database that would include information on number of HPT blades per engine?

texts:
I am attempting to compile information on the number of high-pressure turbine blades across a wide range of turbine engines. Currently, I have only been able to find this information through brut force searching and I wanted to know if an engine database with this type of granular information exists?

Additionally, I have searched through Jane's but wasn't able to locate the appropriate information.

Thanks in advance for any help.


texts: Do I need Customs clearance to fly an N-registered aircraft from Italy to Switzerland?

texts:
I need to fly from Italy to Switzerland in my aircraft with N markings.
I've been told I need a clearance from a customs office within an airport prior to crossing the border. Is this true?


texts: What are the differences between types I, II, and III emergency doors?


texts: Is it always the case that any one STAR leads to all the runways?

texts:
I was making an addon for a flight simulator and I am having a problem figuring this scenario out:

Let's take CYOW - Macdonald Cartier international.

It has 6 runways: 04, 07, 14, 22, 25, 32.
It has 5 STARs : CAPTL4, DEANS8, LEAMY3, MEECH1, RIVER2.

For this specific airport every STAR can be used to approach runway 07,14,22,25 and 32. (Runway 04 isn't used for arrivals at all.)

I was wondering if this was the case for every airport or is it different? I'm not sure if my wording was right. I'll try to clarify it to the best of my abilities if further clarification is needed.


texts: How close do you have to be to an underwater black box to detect it?

texts:
The news keeps talking about the black boxes on aircraft that end up in water, and one thing that keeps coming up is the underwater locator beacon that transmits a signal for 30 days if it gets wet.

What kind of signal does it transmit and what kind of range does it have?  I'm guessing that the depth of water that it is in will affect how far away that it can be detected, but by how much?


texts: How do I explain what makes an airplane fly to a non-technical person?

texts: As an engineer I can explain in very technical terms exactly what makes an airplane fly, however, it isn't easily understood by non-technical people.  How can I explain it to a non-technical person, or a nine year old, in a way that isn't really incorrect but is far less technical than what we learn as pilots?


texts: Was the colliding object in the Guadalajara accident ever identified?

texts:
In December, four months ago, a 737 landing in Guadalajara apparently hit an object and damaged its nose. At the time it was suggested that it might have been a small drone.

Has the object been positively identified?


texts: What are the factors that determine the speed flutter appears on wings?

texts:
I'm doing a study on the flutter phenomenon of airplane wings. I'm interested in factors that influence wing stability, and how one can increase the speed where flutter starts.

What are the parameters that determine this speed?


texts: What is the "one-in one-out" FAA rule for IFR traffic landing or departing at an airport without a tower or at an airport with a closed tower?

texts:
Does the rule say that only one IFR aircraft may land or depart at an airport at one time? I'm having trouble finding the official rule in an FAA document.

What about other VFR traffic that may be flying in the traffic pattern doing practice touch-n-goes? Would that activity be affected by the rule?


texts: What does the balance ball actually indicate?

texts:
Given answers and comments from a previous question, I realize that I need to clarify what the ball actually measure. I think it does not measure side slip but sideways acceleration, but I'm not quite sure.

Let's say, I put a ball in a roller coaster. Whatever the maneuver performed, there can't be side slip (no wind, the roller coaster is basically a train). Those maneuver include:

boat turns (the ball should be on the external side of the turn)
straight horizontal trajectories (the ball should be centered)
straight trajectory with a bank angle (the ball should be on the lower side)
a simple roll

How does this differ from in flight situations? Given what the ball actually measures, what makes it reliable to be used as a side slip indicator?

bonus question: if I take a long aircraft (e.g. a AN-225) and put a ball in several places in the aircraft, will all those indicator concur in a not coordinated turn?


texts: Why can a plane land in zero visibility conditions but not take off in zero visibility?

texts: After waiting hours for a flight departure delayed because of heavy fog, I wonder why planes can perform an instrument landing with no visibility, but cannot take off without a minimum visibility.


texts: Can the Master Caution illuminate without the System Annunciator Panel on the 737NG?

texts:
Does the master caution light illuminate only with the System Annunciator Panel?
Or is the master caution illumination also connected to the related system panels?
I mean if there is an indication on a system panel and the System Annunciator Panel is inop due to some issue, does the master caution illuminate alone?


texts: Does runway 32/33R at Madrid actually have a kink in it?

texts:
In this satellite image of Madrid airport (MAD/LEMD)...

Source:Google maps satellite view
Alternate link from maps.google.nl still renders incorrectly for me, but appears fine for others...

...it appears that there is a very noticeable left kink in the landing area of runway 32/33R.

According to what I can interpret from Jeppesen's airport data, there doesn't appear to be any indication of this kink:

Page 50 of Jeppesen hosted by uvairlines.com.

Is that kink actually there, or is it an artifact of Google's processing of  different images? There is obviously something going on, as you can see both RWY32 & RWY33 markings in the image, while Jeppesen clearly identifies it as 33.

If that kink is actually there, what impact does that have on a pilot landing? I believe the touchdown target is the two long, solid bars at the top left of the image, which excludes the kink, however, there is enough rubber to indicate that touchdowns have occurred much closer to the threshold than that.


texts: Why is the assumed Lift-to-Weight-Ratio for the limit drop test for heavy aircraft (FAR-25) higher than for small aircraft (FAR-23)?

texts: The FAR-25.725 assumes a Lift-to-Weight-Ratio L/W = 1 for the landing gear drop test while the FAR-23.725 assumes only L/W=0.667. This factor affects the load inertia factor n which is also needed for structural analysis. Does anybody have an explanation for the lower assumed Lift-to-Weight-Ratio for smaller aircraft?


texts: How can I calculate distance based on altitude and glideslope angle?

texts: How do I calculate the distance to touchdown when the glideslope angle is different from 3°? For example, you are 670ft AGL on a 3.2° glideslope approach; what do I change in the formula to calculate the distance?


texts:
https://en.m.wikipedia.org/wiki/Aircraft_fabric_covering
This article states several early aircrafts that successfully used cotton as wing skin including Wright flyer.  "Colditz Cock" glider had its wingskin made from bedsheets plus this guys

             used bedsheets to make their wingskin and the plane kinda took for like 2 seconds.
Can a  good,strong bedsheet successfully replace tedlar in an airplane without any problem?


texts: Is there a reason for a jet liner to raise the nose wheel early during the take-off run?

texts:
This video shows a 727 apparently rotating too soon.

The take-off run starts at 2:00 minutes and at 2:11, you can see the yoke is pulled back by the elevators rising.

It seems to me that this is no mistake and that the early pull, held until the main wheels leave the ground and accelerating with the nose wheel held off, is very deliberate.

Is there a solid operational reason for doing this?


texts: Why choose to ditch in the sea over bailing out?

texts:
I recently watched the film Dunkirk (I highly recommend watching it).

Without wanting to give away too much information about the film, a Spitfire pilot is flying over part of The Channel. They lose their engine and state the sea looks calm and opt to ditch over bailing out.

Why would a Spitfire pilot choose to do this? Is ditching in the sea really safer than parachuting out?


texts:
I was wondering how ailerons work on fighter jets. I came across this after hours of research.

Is that how fighter jet ailerons work? Is their a better picture or image that would be better. If there is please post it to help me understand. I've researched for so long on this subject with no avail except this picture that helped me understand it. Thank so much!


texts: Does an airfoil drag coefficient takes parasite drag into account?

texts:
Im trying to understand why does L/D MAX, (the top of the polar curve that computes CL & CD ratio for any airfoil) is also the lowest point of the total drag curve.
Im guessing the reason is that CD curve is not just about induced drag as I thought.


texts:
What is the difference between azimuth and heading?

I understand heading, track, radial, course and bearing but I don't know what azimuth is. I rarely hear it used. The Wikipedia definition is a horizontal angle measured clockwise from a north base line or meridian. How does that differ from heading?

Bonus question: when atc tells you there's a plane at your 2 o'clock, is there a word for that?


texts: How does the ICAO VOR separation apply to reciprocal radials?

texts: If two aircraft are on VOR radials that are apart by 15 degrees or more and one aircraft is at least 15 DME out, they are considered laterally separate. I read this rule in ICAO documents but my question is what if radials are 180 degrees apart and one aircraft is 15 DME out? Would they still be considered separate? I don't think so because they would be reciprocal to each other in this case. Then what are the limitations of above mentioned VOR separation rule?


texts: Why does the 747 have 4 engines instead of 2?

texts:
If the 747 can fly with two engines, why does it have four engines?

What is gained by adding another 2 engines?
Flights over the ocean?
Fuel savings?
Safety?


texts: How do I calculate the Reynolds number of a wing with wing chord,1.2m and speed of 60km/h


texts: What does it mean when an aircraft engine is de-paired? e.g. the PW1000g engines being de-paired because of issues in the LPT or the Rolls Royce Trent 1000 engines due to excessive corrosion on some of the turbine blades?


texts:
I've read many accident reports, and seen reconstructions, where instrument failures, disagreeing sensor sources and auto pilot faults have led pilots into believing that they are over speeding when they are not (think AF447), are descending when they are actually climbing etc.

It seems that in all cases where this has led to a stall, the stick shaker has activated but the PF does not take the correct immediate action for stalls, instead continuing to believe the erroneous information they are being fed.

I understand the psychology of why this might be but is does strike me that many lives would have been saved if power up nose down had been applied.  I've not found a case yet where the shaker was wrong. This leads me to wonder...

How reliable are stick shakers?  Should they always be trusted?

Some older types even had an automatic stick pusher but this does not seem to be present in modern designs.  Is this a consequence of shakers not being infallible?


texts:
Take a good look at the small dots • on the bays of this two spar wing.

My question is:

Are the drag and anti drag wire as seen in bay 1 supposed to connect to the root of the compression tube
Or to the intersection between the wing spars and compression tube as seen in bay 2 or
are they supposed to connect to the wing spars as seen in bay 3?

In other words, which bay is set up correctly? 1, 2, or 3?

This is the point I'm at in my project, your answer will be much appreciated.


texts: What data is displayed on civilian ATC radar screens?

texts:
I am developping an ATC radar for a simulation.

I don't think there is any standard for radars to show aircraft data on radar screens.
But there should be general data to show on radar screens.

For example:

CALL SIGN
ALT ASSIGNED ALT
SPEED HEADING

Can the data shown be changed on the clients?
Is there a difference between ground radar and air radar displayed data?
Is there any standard or can you give me any examples?


texts: Is it possible to take off on an elevated short field by "falling"?

texts:
I understand this may be a dumb question to ask, but - in the opening sequence of Golden Eye - James Bond chases after a plane that has rolled off the side of a cliff in his motorcycle, and then somehow (movie magic) climbs into it and pilots it away.

I am not asking about the physics of the motorcycle stunt - except keeping it to the aircraft part:

Is this something that can happen in real life - that is, an elevated airfield so short, that the plane has to "fall" to obtain enough speed to gain lift?

Has something like this ever been attempted, even if simply as an exercise in flight dynamics?


texts: Is airframe heating a concern at subsonic speeds?

texts:
It is a well-established fact that airframe and skin heating due to air friction is a significant concern with supersonic aircraft.

However, below Mach 1 (i.e. typical commercial aircraft flights at normal cruising altitudes), is there any sort of measurable heating to the airframe/skin that can be observed or needs to be dealt with in some manner?


texts: What were the make and model of the engine that failed in flight Southwest 1380?

texts: Regarding the tragedy of Southwest 1380 flight on 2018-04-17 involving an engine failure, what company manufactured that engine, and what engine model/type was it?


texts: What extreme measures might a pilot take to avoid extreme weather?

texts: What kind of extreme weather would justify a pilot of a commercial airliner taking avoidance measures to the point of likely stall?


texts: Why is there conflicting nomenclature for the 1,000 ft runway markings?

texts:
The two thick solid lines on runways at 1,000 ft from the end of the threshold are called "fixed-distance markers" in some documentation, and in others, it is called the "touchdown zone marker".
Are they two different things, is one right and the other wrong, or are they truly interchangeable terms?
Airman Knowledge Testing Supplement for Instrument Rating, page 116

AIM 2-3-1 from FAA.gov

Both of these above examples are Precision Instrument Runways.


texts: What is decalage and how it affects airplane performance?

texts: What is decalage in airplanes and how important is it in respect to  airplane performance?


texts: How are wood and canvas wings able to sustain damp and bad weather?

texts:
Small aircraft have used and still use at least for wings, and perhaps for fuselage, material like wood and canvas, as visible on the bottom side of this wing:

Robin DR400, source: aeroVFR

Which kind of fabric / which treatment are used? What are the limits:

Are such structure able to withstand bad weather, rain, hail...
Refresh periodicity
Maximum wing load / aircraft size


texts: Why don't small planes use turbine (turboprop) engines?

texts:
Turboprop engines are more fuel efficient1, lighter for the same power, mechanically simpler and consequently more reliable.  They are also slightly easier to operate (no need to fiddle with mixture) and burn cheaper fuel. As a result they replaced piston engines in all transport aircraft long ago. So why didn't they find their way into small GA planes (basically everything above 8-10 seats uses turboprops, but in the 4-seat category, nothing does)?

1Actually looks like I was mistaken. Reciprocating engines seem to be more efficient.


texts: Do modern airliners have a higher Gust Load Limit than an older airliner of the 50's or 60's?

texts: I ask this because the BAC 1-11 had a Gust Load Limit of ~66 fps, and it had a structural failure in a thunderstorm. Many websites say aircraft design has improved since then, so has the Gust Load Limit been changed, and if so, to what?


texts: How does a wing mounted jet engine on a supersonic airplane prevent the interference in the flow due to Shock?

texts:
Wing mounted jet engines face the free stream at Mach number 1 or above, and they work perfectly for Mach numbers below 1 as well, even though the free stream characteristics change a lot after Mach 1.

How do the engines manage to work despite the fact that after Mach 1, the Shock waves would try and disrupt the normal airflow?
If the engines are optimized to work at above Mach 1, does this cause any trouble for them to work under subsonic conditions?

Don't confuse with "Why cant jet engines work with supersonic flow?"


texts: What aerodynamic data exists for the Yak-130?

texts:
This is one of 3 question in "series" - one question split up in 3 to better reward those responding about each aircraft. Other questions: A-10 L-159

Yak-130 is one 3 planes that are used in the ArmA 3 combat simulator, but its aerodynamics modelling currently lacks significantly. I'm planning on writing a short "essay" to developers regarding what and how can be specifically fixed in the flight model, but I'd like to back my research with some hard data. Specifically, I'm interested in any of the following:

L/AoA
D/AoA
Side lift/SA (Slide angle)
Max G/velocity
Flight envelopes

Torques can well be left out - it's not a full fledged simulator, but the above data can give quite a good estimation of high level characteristics already

Are there any good sources on any of the above data? Low-mach data is good enough for me.

I understand this is a tall order, but, well, SE is for expert answers - maybe a wonder happens and someone here has it? :)


texts: Why do aircraft cockpit displays use uppercase fonts?

texts: I've seen many images of aircraft cockpit displays and instrument or control labels that all seem to use uppercase lettering, even though there seems to be a lot of evidence indicating that mixed case lettering has superior readability. Why is that?


texts: Do services still apply foam carpet on belly landings?

texts: From decades I have been reading that, fire services would spray foam on the runway, in order to avoid fire, on a belly landing. Is this procedure still being used? If not, what would be the safest procedure?


texts: Will manually removing nicks from compressor blades significantly affect the operation of the compressor?

texts:
I've recently found a channel on Youtube where a jet engine technician goes into great detail about the work he does on maintaining and repairing jet engines

In this particular video (and also an older prequel to it), he demonstrates removing nicks from compressor blade leading edges and subsequently smoothing out the leading edge. One thing that caught my attention was the tools he used: files and 100- and 400-grit sandpaper. He basically went over the leading edge by hand, removing a small amount of material in the process.

With the tools and the method, there is obviously no precision.

Is it actually acceptable to modify compressor blades that way? To what extent does it affect the operation and efficiency of the engine, if, say, some compressor blades are missing a millimetre off their chord, or have lost their twist by a few degrees?

I guess a related question is - what precision are compressor blades designed and built to?

Thanks to ymb1 for pointing out a related question, but I'm more interested in a quantification or analysis of the impact to the engine performance. It seems that the linked question explains the term blending (which is mentioned in the video as well), but did not go into details about performance impact.


texts: What happens with the avionics if in midair there is loss of power or fuel flow interrupted?

texts: What happens if in midair there is loss of power, how will the avionics perform in such a situation (cockpit display, flight plan)?


texts: Why does pressure remain constant in the boundary layer?

texts:
From Fundamentals of Aerodynamics by JD Anderson.

It can be shown experimentally and theoretically that the pressure
through the boundary layer in a direction perpendicular to the surface
is constant. That is, letting pa and pb be the pressures at points a
and b, respectively, in Figure 1.47, where the y-axis is perpendicular
to the body at point a, then pa = pb.

But, there exist a velocity gradient on the boundary layer. Doesn't this violate Bernoulli's equation? Does this assume pressure remains almost the same in the viscous region or I am missing something?


texts: What year did the seat belt sign come in to use?

texts: What year did commercial airlines start using a lighted seat belt sign?


texts: Could landing gear weighing scales be used to detect lack of lift?

texts:
There have been several crashes due to ice on wings destroying lift. One of the issues with this is that you can't detect that you don't have sufficient lift until you're already in the air, way too late to abort.
Some aircraft have weighing scales in the landing gear. Could these be used to verify the expected lift, and abort if an anomaly was detected before $V_1$?


texts: How do you properly enter the NDB34 published approach at Friday Harbor (KFHR)?

texts:
I'm having trouble figuring out the correct procedure to enter an approach such as:

Let's say you are cleared from ISLND for the NDB approach.  How do you maneuver safely and legally to the the outbound leg once you reach the IAF?

My guess is the correct way would be a turn to the outbound course from the NDB.  Then a right turn direct to the NDB and a direct entry to the outbound course, then proceed as charted.


texts: Where is this VFR reporting point ("Water Tank" near Thousand Oaks, CA) in real life?

texts:
I was looking at the VFR sectional near Thousand Oaks, California. The chart has a "WATER TANK" labeled, but I see many water tanks in Thousand Oaks on the Google Maps satellite view.

Does anyone know which water tank they are referring to on the sectional? And why would they choose something so easily confused with other "water tanks"?

(skyvector.com)


texts: Is this statistic about the fatal accident rate correct?

texts:
This link says that:

  fatal accidents occurred once every 200,000 flights in the 50s and 60s. Now, fatal accidents only occur once every two million flights

While many sources, including this one, agree that the average number of commercial flights per day is around 100,000.

If that is the case, then we should see a fatal accident every 20 days or so (2 million flights), but in 2017, there were no fatal incidents on commercial flight at all.

What is the explanation for this? Is it just that the first link is plain wrong?


texts:
Posted it here originally.
There are keys (push buttons) on the front panel of an avionics device that fits inside the aircraft cockpit. I need to know the material of which those key-tops are made from.

I can guess the material is some type of clear transparent plastic and then its painted with black color. The text on it is un-painted key surface. There is green light under the keys (buttons). That green light glows the text (due to transparent plastic) on the key-top as green in color.
This cockpit device is from a very old aircraft model of 1950's so we can say it is not using any modern high performance thermoplastic or composite material. How can I best identify the material of these key-tops?
Edit: How do I know if the key-top material is compatible with NVIS (Night Vision Imaging Systems)?


texts: Why does part 135 require a maintenance log on board the aircraft, but part 91 does not?

texts:
During a dispute within friends, it came to my attention that in 135.65 the maintenance log copies must be present in the aircraft, and that 91.407(b) and 91.417(c) have similar rules, but, meanwhile, as indicated in 91.203 the "maintenance logs" are not necessarily maintained and be present in the aircraft. Why is this?
Why didn't a school provide the maintenance logs in the aircraft, but only the airworthiness certificate?
I don't understand the reason behind this; if it must be present in the aircraft for 135 operations (air taxi) why it is not present in 91 operations? Safety wise speaking, I think any pilot who commands a plane, abused by many different people, would want to know what was in the maintenance logs?
I tried to understand the reasoning: maybe the regulators think that it will create another responsibility for PIC? Or maybe this added responsibility will diminish the part 91 owner/operator responsibility? If anybody can explain the underlying rationale for the legislation ıt will be great.


texts: Is if safe/legal for an aircraft to return to cruising altitude after passenger oxygen masks have been deployed?

texts:
I was reading reports [1,2,3,4] about a recent Air China flight where one of the pilots was allegedly smoking and, in an effort to prevent the smoke circulating to the cabin, accidentally de-pressurised the aircraft. The passenger oxygen masks were deployed and the crew performed an emergency descent. Eventually the problem was rectified and, after the cabin re-pressurised, the plane climbed again and completed the flight.

The bolded parts of this story are what I'm asking about. If the oxygen masks have been deployed and the plane returns to cruising altitude, then there is no supplementary oxygen available for passengers in the event of a second de-pressurisation incident. This seems unsafe. (I recall reading that the oxygen supply only lasts 12 minutes and is intended only to last for the duration of an emergency descent.)

What are the rules around this situation? Can an aircraft safely/legally climb again after passenger oxygen masks have been deployed?


texts: Why don't FMCs automatically include up-to-date oceanic route definitions?

texts:
In modern FMCs, flying an oceanic route requires inputting coordinates directly, often in obtuse formats (which are arguably prone to typos, but following proper procedure and a step through the route map generally prevent this being an issue).

Working with an example: North Atlantic Tracks, or NATs, are a set of roughly parallel airways in the North Atlantic, generally spanning from Canada's maritime provinces in the West to the Irish coast in the East. Because of frequently changing conditions in the North Atlantic, these routes undergo changes every few days, which are conveyed to pilots before each transatlantic flight.

Having said all that: modern FMCs are pretty clever, and they can (and regularly do) pull down data from the network, including in-flight weather data, for example. Why don't modern flight computers use this to also download oceanic route definitions if manual input is required rather than using a company route?


texts: How do airlines replace a pilot at the last minute if they're unable to fly?

texts:
I would like to know what decision do the commercial airline carriers take when there is emergency case of a pilot who cannot fly the plane because of personal emergency conditions?
Emergency conditions could be the pilot falling sick with a medical emergency, family member, close relative death etc.
The event has happened just a few hours before the final plane departure.
Does the co-pilot fly the plane in that case? Do the specific airline carriers always have pilots in reserve?


texts: Is this paper's description of ATC services over the internet actually practical?

texts:
I read this paper recently; it's titled ATC over the World Wide Web,
a case study and prototypical implementation. The paper says:

  "In the context of radar surveillance for regional airports DFS
  (Deutsche Flugsicherung Air Navigation Service) must provide a
  possibility for the controller to monitor and control the dedicated
  airspace in a safe manner without the need for a complex and locally
  installed radar surveillance system. In other words: The aim is to
  provide the controller in the tower with a PHOENIX Controller Working
  Position (CWP) over the World Wide Web (WWW). The CWP receives the
  surveillance data over the Internet. This approach allows the usage of
  a standard PC connected to the internet in a standardized manner (e.g.
  DSL)."

The PHOENIX is a Radar Data Processing System (RDPS) for air traffic control that's been developed at the Deutsche Flugsicherung (DFS).

My question is: why does a client need to send their ATC over the Internet for this? DFS still has to set up the hardware in the client tower. So, why doesn't the client use the conventional method to transmit/receive ATC and then, if needed, send the ATC through the Internet (on the ground) to the vendor (DFS) for real-time processing?


texts: What is the speed limit in European airspace?

texts:
In Did this aircraft illegally exceed 250kts below 10,000ft? it was mentioned that unlike here in the US, EASA does not have a 250 kt. speed limit below 10,000 ft.

So does this mean that are we allowed to go as fast as we want?

Mach 8? ;-)

What is the maximum indicated airspeed specified by EASA when operating in the European Union?


texts: WAAS LPV approaches can have decision altitudes as low as 200 AGL, the same as many Cat I ILS approaches. Previous opinions on the Internet have quoted the FAA as saying LPV is considered a non-precision approach, but many of these entries were made more than seven years ago, when the technology was much less mature. Does anyone know if this is still the FAA's position, and are there any RECENT references to their position?


texts: How to properly enter a holding pattern?

texts:
Once ATC have assigned me a holding pattern, how do I determine where to intercept it?

And once that I have determined the intercept point, how do I proceed?

I have heard about the teardrop and the parallel entries, are there others? How do I select the most appropriate entry?

During the intercept maneuver, can I assume[1] that the appropriate airspace is free (since ATC told me to intercept that hold) or there is high risk of coming close to other aircrafts?

[1] this does not mean that I will not look at the radar/out of the window, is just to know the level of attention that I have to pay to this aspect.


texts: May I fly with passengers on a homebuilt experimental airplane with only a simple PPL?

texts:
So I’m in the market for a small two-seater. I see a lot of homebuilts and experimentals listed that are perfectly priced. I have my private pilot certificate but that’s it.

Would I be able to fly an experimental with a passenger?

Do I need something special if I wanted to buy one of these planes?

Currently I live in Ohio, United States.


texts: Why is the flow ahead of a shock wave chaotic?

texts:
Here is the image of a shock wave on a cone in a small supersonic wind tunnel, the white lines are the condensations formed in the test chamber due to flow expansion.

Why are the condensations so chaotic ahead of the shock wave?

I know that the flow shouldn't fall down on the cone but still, why is it so chaotic?

Note: the chamber is 4-5 cm long.


texts: What trajectory do I fly if bearing angle is constant?

texts: Let's suppose I am flying at constant bearing (initial and final heading are equal and constant) relative to the geographical north pole; what kind of trajectory would I be flying?


texts: Vector to final on RNAV approach with the Intermediate and final segments are not aligned

texts:
Consider the RNAV 30 approach to C83 (Byron, CA),

On a recent training flight requesting vectors for the approach, ATC pointed us to the MOVDD IF before cutting us loose (informing us that we would be getting a vector to that fix). The segment between here and the FAF is 11 degrees off from the final segment. On a GTN650 at least (and I assume other similar Garmin devices), selecting “Vectors” as the approach method gives you the FAF line with your deviation from it & sequences from the FAF. This seems not correct for flying this particular approach. The best my CFI & I could come up with was to enter the approach as being flown from the IAF (SMONE) then select “Direct to MOVDD” sometime before reaching it (such as when ATC gives the last turn), after which the GPS will sequence to the intermediate-to-final segment. But this seems non-standard. What do others do in this situation?


texts: Why does wake turbulence seem to move upward on touchdown?

texts:
Source of the first photo

I saw this photo of business jet touching down (first picture) and the smoke of tires forming wake turbulence . as I have provided other pictures (second and third) of "what we have seen and know about the theory of wake turbulence" , you can see this strange upside down form of wake turbulence . simply what is the reason ?


texts: What is garbling in the context of radar?

texts: Garbling is a problem known to affect secondary surveillance radar (SSR). What is it and why is it a problem?


texts: Is seating distribution planned in airliners or is it left to casuality?

texts:
One thing I have always wondered when taking intercontinental flights is the way passengers are distributed in an aircraft. It seems to me that in some way people of different ethnicities are purposely mixed. I have the strange idea that this is preset and done mostly for security reasons.

Seeking for clarification on this matter. Please do not get me wrong as I am not trying to classify different types of people!


texts: How do I get attention on a busy radio channel?

texts: As I understand it (I'm not a pilot), radio communications are a more-or-less first come first served proposition. If I'm in busy airspace with near constant communication between ATC & aircraft, how do I break in to make contact with the ATC for whatever purpose necessary (establishing comms to enter airspace, or whatever the situation may be)?


texts: You can tracks planes, automobiles and boats on Internet, but does tracking technology exist for drones and if so, can you follow them online?


texts: To receive an SVFR clearance, does the airport need to be reporting IFR conditions?

texts:
If conditions at a towered airport are not IFR, can pilots request a special VFR clearance? For example, at a Class D airport, ceiling 1300 broken, 10 sm visibility is technically too low to remain in the pattern (assuming a 1000 foot AGL pattern and maintaining at least 500 feet below clouds), yet it is not IFR.

With a Special VFR clearance, the pilot would be able to maintain a 1000 foot pattern and remain clear of clouds. If the pilot requests SVFR, will the tower grant it?


texts: Does kerosene have a higher octane value than gasoline?

texts: One of my coworkers says his chemistry teacher told them (a long time ago) that kerosene has a higher octane value than gasoline. My understanding was always that aviation gasoline has octane value above 120, but it is really gasoline, while kerosene is more like diesel fuel. What is the truth?


texts: What are the EU-equivalent terms of the FAA ATC tower, TRACON, and center in radio calls?

texts: Does ATC in the EU have equivalents to the US FAA tower, TRACON, and center facilities? What are they called?


texts:
Airplanes are routinely launched from ocean going vessels, namely carriers.

Missiles are routinely launched from submarines.

Has an airplane ever been launched from a submarine?

From questions about what qualifies:

Manned or unmanned is ok, but payload mass has to approximate a least a small person
One way trip is ok
Airboat dropped in the water is ok
Airbreathing primary propulsion required, rocket assist for takeoff is ok
Wings for lift are required, control fins alone do not qualify


texts: Is it possible for two aircraft to have the same MSN number,  I was under the assumption the an MSN was a unique identifier for an aircraft


texts: What is this instrument that has "PACK" written on it and a temperature scale?

texts: All I know right now is that it’s made in 1973. Another instrument I have is from a b727 and is dated 1982. This one I have no clue. Serial number- H 2590. The brand is Amphenol. That’s all the info I can find. I have some pictures.


texts: How tight should passengers wear the seat belt?

texts:
How tight should a passenger wear the seat belt?

During takeoff and landing and other moments the seat belt sign is on, I usually pull the belt as tight as possible. This is little uncomfortable, so I loosen it a bit when the seat belt sign is off. I think that one or maybe two fingers might fit between the seat belt and my body.
Is this a good idea? Would wearing the belt as tight as possible give a greater risk of crushing my pelvis bone or something?

Please specify whether there is a difference between a situation where the seat belt sign is on and a situation where the sign is off.


texts: Is there a formula to compute the elevator angle to stabilize takeoff?

texts:
I'm building a ground effect vehicle, but I'm failing to stabilize the lift-off. At a certain speed, the lift force is equal to the weight force, so the vehicle lifts off. But this implements a change in angle of attack, so also an uncontrolled change in lift, as can be seen in this video.

I know that I can solve this with an elevator that can oppose the change in angle of attack. Now I'm searching for an equation to calculate the elevator angle to get a stabile and controllable lift off.


texts:
I've heard that the engines on a commercial air transports are typically mounted with 2 or 3 bolts. Is this true? If so, how big are these bolts and what are they made of?

I'm optimizing a bolted joint for my FEA class, and I'd like to check my results against reality.

PS: The Factor of Safety on such a bolt would be nice too!


texts: How do I get an airworthiness certificate for a prototype aircraft?

texts: If I were to build a plane of my own design as a prototype for possible sales, what steps would I need to take to get an airworthiness certificate from the FAA? If it's truly a certified aircraft and not a homebuilt?


texts: Why are highly cambered airfoils rarely used in propellers or wings?

texts:
Highly cambered airfoils like the Seligs and Epplers are hardly ever used in propeller or wing sections. Why?

Does their performance reduce at high Re? Are they only adequate at low Mach, low Re?

The question only regards the aerodynamics. Ignore fuel storage and structural elements.


texts: How to differentiate two flights with the same flight number that arrive on the same day?

texts:
I'm currently working on a piece of software that includes flight information. I have access to flight schedules and I'm making each days flight unique based on flight number and the date that it arrives.
I've hit a problem trying to differentiate flights that arrive on the same day though.
Example:

On Sunday, Flight LS1494 leaves at 19:50 and arrives the next day at 00:25.
The next day, on Monday, LS1494 leaves at 16:40 and arrives at 21:15, making it arrive twice in one day.

Is there a standard way to differentiate these? I have one source of data that includes an "Operational Suffix" of "B" for the flight that originally left on Sunday but I'm not sure if that is actually relevant.
I could include the actually arrival time to identify them however sometimes that scheduled time changes and doesn't get updated immediately which can cause problems.


texts: Why have different flights with the same flight number?

texts:
It's not uncommon for two distinct flights to have the same number.  For example, DL10 consists of a narrow-bodied jet flying from Denver to Minneapolis–St Paul and then, two to three hours later, a wide-bodied jet flying from MSP to London Heathrow1; AA55 splits Manchester–Chicago–Orlando. This question gives another example and asks how ATC would deal with the situation where one of these flights is delayed leading to both being in the air at once.

But that begs the question of why one would give the same number to two flights in the first place. I understand that, historically, it was common for a long-haul flight to make several stops for refuelling but it's a long time since that was common and, here, we're talking about completely different aircraft and not just a refuelling stop.

What advantage is there to an airline in assigning the same number to two flights like this?

1 At least, it did when I posted the question in early October 2017. Now, a month later, it's a narrow-body from Kansas City to Minneapolis and then a Minneapolis–Heathrow flight. On some days, there's about 45 minutes between the two; on others, a little over three hours.


texts:
I frequently fly within India as part of my work and every time I am sitting in an airliner preparing to take off, I observe a lot of differences in each crew handling the take off or the ground crew procedures.

I would like to understand if there is any board that certifies these crews and airlines for safety, like the FAA for the US, if these information are released to the public, like a certificates that are issued for public information.


texts: Are there any drawbacks to requesting progressive taxi every time?

texts: Unless you know the airport like your own backyard, it seems like requesting progressive taxi would always be the safest option to essentially eliminate the possibility of taking a wrong turn or busting a hold short. Aside from the risk of slightly annoying the folks in the tower, are there any drawbacks to requesting progressive taxi as standard operating procedure?


texts: Do I get two different certificate cards if I earn both a pilot and an instructor certificate in the US?

texts:
I would like to know if one will be receiving two separate licenses in case he/she earns a pilot certificate as well as a ground instructor certificate in the US.

Do the certificates come separately on two different plastic cards? If yes, does the certificate number change between them, or do they have the same number?


texts: If I fly a balanced turn long enough, will the AI show I'm level?

texts:
Attitude Indicators are essentially gyroscopes. Mechanical gyroscopes have a "rigidity in space" property, which allows them to preserve their orientation when the support rotates. However, like spinning tops, gyroscopes will also slowly right themselves up due to gravity; otherwise the AI will show pitch down as the plane travels forward.

If I keep an airplane in a balanced turn long enough, is it possible that the gyroscope will right itself to the fake gravity, and show that I'm straight and level?

What about ring laser gyroscopes?


texts: Is there a difference in use of external lights for taxi in/out or takeoff/landing?

texts: Will there be a different light pattern (like turning on/off different exterior lights) between taxi in and taxi out, and between takeoff and landing?


texts: Do aircraft manufacturers like Airbus or Boeing charge the airline, when they assist in aircraft accident investigations?

texts: Most of the time, when an aircraft crashes or has an accident, the manufacturer also assists in the investigation. Is this a pro-bono kind of effort on part of the manufacturers, or do they charge the airline for it?


texts: Suppose that you dropped an uncontrolled, dummy glider into the air. You want it to always face into the wind by design. Would it be possible? If so, what would such a plane look like?


texts: What problems would the early F-16 have if they were to fight during night?

texts:
From Wikipedia:

  Designed as an air superiority day fighter, it evolved into a successful all-weather multirole aircraft.

There is no citation for this, so I suppose first asking if this is even true should be the first order of business. However, my real questions are the following.

Assuming the quote above is true, what difficulties would early F-16s (F-16A?) have with night operations when encountering enemy aircraft?
What is it with modern F-16s that make them better suited for engaging enemy aircraft during the night? Obviously I know they have more modern avionics, but specifically, what is the difference in this night fighting context?


texts: How are the system development and integration procedure separated for Integrated Modular Avionics?

texts:
I'm reading this paper about IMA (Integrated Modular Avionics) and I don't get the splitting of the development and integration procedure. In page 4 it says:

  Airbus has to modify the conventional development processes and responsibilities. The IMA system development and integration procedure is split between

  the Avionic Module Supplier
  the Aircraft System Manufacturer
  Airbus

Who is the Aircraft System Manufacturer? Which is its function?

My doubt is principally about this paragraph that is few lines later:

  The open IMA concept puts the assembler into the position of the IMA system integrator. The
  development responsibility for the single systems and their functions remains at the system
  manufacturers. The avionic module supplier provides “empty” IMA modules to both, the
  system manufacturers and to assembler. The system manufacturer applies the CPIOM for the
  local function implementation and qualification. The assembler, in turn integrates the own
  empty CPIOM with the ADCN on the aircraft in order to establish the basic computing resource
  for different system functions.


texts: What stops an international private airplane from landing outside of airports with a customs zone?

texts:
Let's say somebody charters a small airplane from Canada and flies into the US (after receiving clearance from the US ATC). After crossing the border, they land on a small airstrip in the middle of nowhere instead of going to an airport with a customs facility.

Would anything stop them from doing so? Would the police be notified immediately by the ATC? Is all international air traffic closely monitored until they pass through customs?


texts: Is "hacking small planes" a separate or larger problem from/than general small-aircraft security?

texts:
Apparently the DHS has issued a "hacking alert" for small aircraft:

  The alert warns if a hacker gained physical access to certain small planes, they could attach a common device to its wiring. This could provide false flight data including altitude and airspeed, as well as possible access to the autopilot system, potentially leaving a pilot unable to tell whether the reading was accurate and potentially lose control of the aircraft.

This involves physical access to the aircraft, which the FAA said "is unlikely."

Is this particularly different from other attacks not involving "computer hacking" that could be mounted given physical access to an aircraft? For example, is this in some way much less likely to be caught via a pre-flight inspection than any other attack on avionics or other equipment, or much harder to mitigate in flight?

Or is this just more Security Theatre from Homeland Security, raising what's essentially already a known mode of failure (potentially from reasons other than a "hacking attack") for which the aviation community already has procedures in place to mitigate it and continues to monitor and improve these procedures as technology changes over time?


texts: Why do shipping companies opt for the Boeing 747 instead of Antonov An-124?

texts:
Both are quad-jets, but the Antonovs can carry up to 150 t of payload and are much cheaper (\$100M for the An-124 compared to \$238M for the Boeing 747-400F).

I understand that MRO is quite an issue for Antonov, but we are talking about the freighting industry, which is less congested and less demanding than the commercial airliner industry.

Is the skepticism of buying a SSSR-era product really founded, or is there in the West a lobbying trying to maintain the Airbus-Boeing duopoly and keeping foreign products out?


texts: Why can't you just set the altimeter to field elevation?

texts: Why do you have to put the current altimeter setting in the kollsman window? Why can't you just set it to field elevation when you're on the ground? I understand why you would have to do it in the air.


texts: Is this equation for propeller thrust correct?

texts:
From dimensional considerations, and assuming that the power $P$ applied to a propeller of diameter $D$ moving at an axial speed $V$ is 100% converted to the acceleration of a mass of air with density $rho$, I have arrived to the following expression for the thrust $F$:

$F=k(P·rho·V)^{1/2}·D$

where $k$ is a non-dimensional constant.

Is that expression basically correct? I'm now editing to include below the derivation, a bit long...

We have a propeller with a diameter $D$, absorbing a power $P$ when moving at an axial velocity $V$ in air of density $\rho$. Let’s assume that there exists a function f such that the thrust $F$ of the propeller is:

$F = f(P,D,V,\rho)$

The variables are thrust $F$, dimensions $MLT^{–2}$; Power $P$, dimensions    $ML^2T^{–3}$; prop diameter $D$, dimensions $L$ and air density $\rho$, dimensions $ML^{–3}$

Five variables are too much. The system can’t be solved unless we have four, one dependent and  tree independent…  So, in place of $V$ and $D$, we take the volume $W$ swept by the spinning propeller in the unit of time, dimensions $L^{3}T^{–1}$

$W = π/4 · D^{2} · V$

There is an non-dimensional constant $k$ such that:

$k = F^a\cdot P^b\cdot \rho^c \cdot W^d$ where $a,b,c,d$ are numbers to be determined.

Switching to the dimensions:

$M^0 L^0 T^0 = (MLT^{–2})^a  (ML^2T^{–3})^b  (ML^{–3})^c (L^3 T^{–1})^d$

Then, the system is:

$0 = a + b + c\\
0 = a + 2b –3c + 3d \\
0 = –2a –3b –d$

$F$ is the dependent variable, so we make a=1

Solving the system:

$b = –1/2 \\
d = –1/2 \\
c = –1/2$

Inserting in
$k = F^a\cdot P^b\cdot \rho^c \cdot W^d$ where $a,b,c,d$
the values of the exponents, and solving for $F$,

$F = k\cdot P^{1/2}\cdot \rho^{1/2} \cdot W^{1/2}$

But $W = π/4 · D^{2} · V$

Now $k$ may absorb the constant π/4, and we get:

$F = k\cdot P^{1/2}\cdot \rho^{1/2} \cdot V^{1/2}\cdot D$


texts: What provides a higher lift to drag ratio, a thick laminar wing or a thinner wing with a vortex generator

texts:
Recent readings have shown the benefits of "boundary layer tripping devices" or vortex generators for reducing drag and maintaining attached air flow at higher angles of attack.

It seems these generators effectively increase the width of the wing by creating an energized
"fence", which further deflects the free air stream, almost acting as a lubricant to reduce friction drag on the surface of the wing and increasing the "bend" of the airstream, thereby increasing lift.

But generating these vortices comes at the expense of increased drag to create them, though they (and slats) could be made to be retractable.

Is there a clear advantage to either a thick laminar wing or a thinner one with vortex generators?  The Reynolds number for the application would be around 200,000 to 500,000.


texts: What was the flight route from New York to Paris that Air France took in 1955?

texts:
I have a photograph of me and my sister in 1955 or 1956 boarding Air France to Paris. I seem to remember the route was:

New York - Gander
Gander - Shannon
Shannon - Orly

Is that correct? I know the return flight (westbound) was that route. Does anybody know how long it took?


texts: smartphones in fligth mode when bad weather conditions?

texts:
when flying form Vienna to Stuttgart, we had a terrible weather conditions, before landing the cabin crew announced that by request of the captain, all electronic devices must be switch off, not allowing even their use in flight mode..

any particular reason for that??
maybe avoiding the selfie effect by millenials if something goes wrong by landing??

thanks is advance


texts: How much lift do supercritical airfoils produce?

texts: Compared to your regular asymmetric cambered airfoil, How much does lift do supercritical airfoils produce?


texts:
I have a question about the PAPI system. One of the first things student pilots learn during their ground school is the PAPI. You get two whites and two reds on a visual approach, you're on the 3 degree glide path. If you get three reds and one white, you're a little low. If you get four reds, then you may consider going around since you're way too low.
My question is: Can we always trust the PAPI lights? Is there no chance the PAPI lights might be wrong, so for example, when you get three whites and one red on the 5 mile final, but you are actually below the 3 degree glide path?


texts: What's the purpose of the cable connected on the top of the fin?

texts:
A321neo has on the top of the fin, backwards, a long tube, which looks like the pitot tube on the Boeing 707, but on the opposite way, and connected on it, a cable (I think because it is a test flight).
What is the purpose of each one?
Picture's credits: www.airbus.com/presscentre


texts: How do subjective experiences in the airliner cabin correlate with meteorological conditions?

texts:
There must be a better way of phrasing this, but: given the passenger's experience of riding through the air, what are the outside conditions that are responsible for that experience?

For example, if the passenger experiences a smooth, quiet ride (like driving on a smooth, newly-paved road), then the external conditions are perfectly still air.

What about the cases of:

a smooth but noisier passage through the air (like driving over a section of road with a different surface - not bumpier, just noisier)
consistent low-level but high-frequency vibration (like driving over a section of road with a regular pattern of deformation)
harder, occasional knocks and bumps (like driving over a road of variable quality)
hard, regular, sustained shaking (like driving fast over a rutted road)
repeated, irregular, harsh movements and lurches (like driving violently off-road)
a single, sudden jolt (like driving across the transition between road surfaces at different levels) - I've experienced this when crossing the transition between land and sea, and when intersecting the trail of another aircraft
a sudden very-high magnitude movement that comes out of the blue, of the kind that causes objects to fly around the cabin

To be clear, I am speaking of straight, level flight in clean configuration, in which different sound and vibration as experienced in the cabin are caused by conditions (pressure, movement, speed, turbulence, patterns of the air) outside - what are these conditions in each case?


texts: What callsigns do UK Medical Emergency Response Teams use?

texts:
I'm making a simulation game and there's a large focus on the humanitarian effort military personnel put in, putting aside the shooting and more on the story. Part of this is a Medical Emergency Response Team (MERT) landing with radio communication in the background, which obviously is using callsigns.

For the purpose of realism, I am trying to find references for what callsigns are used for these MERT aircraft/teams. Does anyone have any idea what a MERT team might be called? I'm looking specifically for UK forces however NATO is also fine.


texts: How can I know the manufacturer of the PFD (Primary Flight Display) of the current mainstream passenger aircraft?

texts:
I'm developing a computer vision software based on the photos of these PFD (Primary Flight Display). How can I know the manufacturer of these PFD of the current mainstream passenger aircraft: B737. B747, B777, A320, A330, A340?
I have tried to Google and to find documents about these aircraft, for example, I know the device reference of the PFD of B737 is G1000 made by Garmin, but for others, it's really difficult to find out the device reference of their PFD.
Here is an example of the PFD of B737.


texts: Why do the missiles on an F-16 point slightly down?

texts:
I've been wondering this for quite a while:  Why do the missiles on the F-16 point down a little bit?

I went and did a little searching and found out that the F-16 isn't the only plane that has this feature, so I'm going assume it's not the F-16s frame specifically.  I also doubt it's tactical because all the weapons are pointing down, regardless of the weapons role in combat. In fact I saw a few photos where the bombs closest to the fuselage were pretty level with the ground (and bombs pretty much always go down, so...)

Does it have to do with aerodynamics, or perhaps ease of loading?  Why is the load-out on the F-16 mostly pointed slightly downwards?


texts: How does the propeller position affect the effectiveness of control surfaces?

texts:
I've found several questions about differences between pusher and puller aircraft, but the effectiveness of control surfaces was not discussed in any of them.

Consider the following three scenarios:

A: Aerodynamic surface in undisturbed flow
B: Aerodynamic surface with a puller propeller
C: Aerodynamic surface with a pusher propeller

In what case is the lift force generated due to the control surface deflection larger? What differences are there between B and C?


texts: Is the longitudinal extremity of an obstacle limitation surface based on the threshold or the displaced threshold?

texts: In a case where a displaced threshold (DTHR) is present, should the longitudinal extremity of the obstacle limitation surfaces (for example, the conical surfaces) be counted from the threshold (THR) or from the DTHR (case of Moroccan airport)?


texts: Why is the extra allowance for wheel installation on A380 in terms of degrees instead of torque/torque percentage?

texts:
When installing a wheel on the A380, the nut is permitted to be torqued an extra X degrees if the holes do not align.

Any idea why its in degrees instead of X torque or percentage of torque value?


texts: How was the endurance test in the Cessna 172 legal?

texts: The flight in the Cessna 172 lasted around 64 days with two pilots switching to fly the plane. To my knowledge both FAA and EASA have rest periods which pilots have to follow. Also the refueling was done by a truck matching the speed and handing over a hose to refuel. How was this flight legal regarding rest periods and refueling maneuver?


texts: Does the rate of turn increase or decrease by turning at a higher speed?

texts:
It is easy to derive a formula for rate of turn in a steady banked turn as:

$$\dot\psi=\frac{g \cdot tan\phi}{v}$$

which indicates that as speed increases rate of turn decreases. This feels counteruntuitive especially given the identity for circular motion:

$$\omega=\frac{v}{r}$$

which would suggest rate of turn increases linearly as speed increases.

Can someone give me some intuition as to why speed has the opposite effect in a banked turn. Given the above I can only think that speed in a banked turn increases radius at a rate greater than it should increase $\omega$ during normal circular motion.


texts: Is this photo of an aircraft in a flood genuine?

texts:
I stumbled upon this picture somewhere on the internet:

I don't believe an aircraft would be able to take off like that; I also don't expect a normal landing be allowed if this were on a runway. I suppose, in case of emergency, it could possibly land into such water. Generally, I think that either this picture is fake or the aircraft was parked at a stand before the area was flooded.

Unfortunately, as the picture was so small, it's virtually impossible to see any details, and thus difficult to analyse for "fakeness". Could this picture possibly be real?


texts:
I recently Stumbled on this Why Planes Don't Fly Faster on youtube and it talked about how less speed is more economical for airlines and he also said something that plane above and below speed of sound will face less air drag, in the region of speed of sound maximum air drag will be experienced. I am not quite able to understand what he meant there?

Question In the first part :
1.  Why planes fly at M .8?
2.  Why there is less drag above and below M 1 ?.

Also in one of the comment someone said

  What generates the most thrust in a turbofan is the bypass air and not the turbine. Usually the fan generates around 80% thrust and the turbine generates around 20%. There are some rare cases where the turbine generates more thrust, but in most high bypass turbofans (which are the most we use today) the fan is what generates most of the thrust.

Question Here : Why turbofans generate most of the thrust with the cold flow?

And that the video is mostly incorrect, can someone guide me here, I am sort of confused.

Lastly : Is that youtube video wrong? , I want to know this because I really liked his way of explaining , and I really want video to be right, but I am confused by the some comments, if one could guide me if video is wrong or right, it would highly appreciated?


texts: Do box-wings suffer from induced drag the same way as normal wings?

texts:
Most wings suffer from induced drag due to a pressure difference above and below the wing causing air to sneak around the tip, forming a vortex. There are various methods to minimize these effects, such as winglets.

However, looking at the Synergy aircraft as an example, box wings have no wing tips. Disregarding any other parts of the aircraft, are the wings actually free from induced drag? Or are they still causing induced drag, just in a way I'm not able to think of with my limited fluid dynamics experience?

Synergy aircraft with box wings (picture source)

I've read somewhere that a traditional bi-plane design is less efficient due to the wings interfering with each other (apparently something addressed by the synergy aircraft by placing the upper wing further back or something), and the upper wing is actually more of a tail-plane, pushing down, thus further increasing the airspeed in between the airfoils if I understand correctly and eliminating the pressure differential from the top of the upper wing to the bottom of the lower wing, and both wings would of course generate normal drag by cutting through the air, but I'm only interested in the induced drag at this point.


texts: What are some first-order drag approximations for airframe/propwash interactions?

texts: What are some first-order drag approximations for airframe/propwash interactions, both for dynamic flight and for static thrust, in a traditional tractor configuration?


texts: Do US state governors have jurisdiction over their airspace?

texts: Do local governments have any control over their local airspace in the US.  Could a governor singlehandedly close or restrict the airspace above his state?  I know the FAA controls national airspace but could a local government enact local measures?  And to what extent could they?


texts: Where can I find electrical pinout of C152 microphone jack and DC bias?

texts:
Would anyone have the pinout and/or specs of the C152 passenger/pilot microphone jack? I'd also like to know what DC bias voltage, if any, the plane provides to the microphone.

Here's what I have so far, which may or may not be accurate:

              Headphone side     Plane Side
Sleeve             GND              GND
Ring         MIC OUT/BIAS IN       ???(?V)
Tip              UNUSED?            PTT?

I've dug through some Bendix/King nav/com radio manuals, but they don't tell you about what to expect on the plane side of things.

Thanks!


texts: What is an airliner pilot's first go-to if he or she doesn’t have a positive climb rate immediately after take off?

texts:
Assuming a typical transport-class aircraft, what would the pilot do if the aircraft does not have a positive rate of climb immediately after takeoff?

Would the pilot just lower the nose to pick up airspeed, then raise it back up once they’re satisfied? Or maybe retract the flaps a bit? Assuming the throttle is at 94% N1, would applying full throttle at that point even stop the decline in speed?


texts: Where can I find official definition of VFR and IFR?

texts:
I know that ICAO Annex 2 'Rules of the air' states rules such as general rules, visual flight rules, instrument flight rules, etc. And aircraft should fly in accordance with either visual flight rules or instrument flight rules, and that is VFR and IFR. If aircraft fly in accordance with visual flight rules, that must be VFR.

But apart from these rigid rules, I image VFR as a flight that should fly with outside visual reference and have responsibility to avoid and separate with other obstacles or aircraft and IFR as a flight referring to instrument to avoid and be separated with other obstacles.

I tried to find more kind explanations(rather than ICAO ANNEX 2) about it like I stated above, but failed. Of course, I could find many documents or information like wikipedia, but there was no official source such as ICAO or FAA documents.

Could you give me some source that define VFR or IFR like as I stated above?


texts: Is an ADS-B IN able to receive signal from ADS-B OUT of the same aircraft?

texts: Suppose I have an ADS-B IN on my aircraft and I am interested in receiving also data sent from ADS-B OUT of my own aircraft. Is it technically possible or are there any issues due to the relative position between transmitter and receiver or anything else?


texts: What is this c. 1948 private plane with a sliding canopy?

texts:
(YouTube)

What is this private plane with a sliding canopy?


texts: Can an Indian operator get approval for ETOPS-120 without first getting approval for a lower ETOPS rating?

texts:
If an A320 aircraft equipped with CFM 56-5B engines is certified capable of 120 minutes ETOPS by the manufacturer as per its AFM, can an Indian operator directly request operational approval for ETOPS-120 from the DGCA? Is this possible without getting approval for a lower rating first, i.e. ETOPS-75 or ETOPS-90?

Note: the request for approval would be based on (a) AFM certification, (b) ETOPS training  to flt. crew and maintenance, (c) implementation of ETOPS maintenance and operational policies and procedures (d) ETOPS CMP compliance, (e) satisfactory in-service reliabilty and operational experience of approx 10 years with a fleet of 15 aircraft on non ETOPS sectors


texts: Do all airplanes have the same turning radius when operating under the same conditions regardless of size and weight?

texts:
Would any airplane in coordinated, turning, level flight have the same turn radius at a given combination of no-wind ground speed, bank angle, and density altitude as another airplane of significant difference in size and/or weight?

For example, if a small airplane and a super heavy airplane could match speeds at the same density altitude, and they both held the same bank angle while holding altitude, would they generally be expected to have the same turn radius if they weren't slipping or skidding?

If yes, what are some examples of exceptions to this if any?


texts: Minimum distance required to turn at maximum speed of an F-16

texts:
What would be the minimum distance required for an F-16 to turn either sideways or upwards in order to avoid a collision (assume an infinitely long wall both length and breadth wise).

Also would it be better for such planes to turn sideways or upwards? Which is faster and requires less distance.


texts: Is it possible to build a paper airplane that will enter a fully developed spin?

texts:
Some students learn best when they can see aerodynamic principles in action. I'd really like to be able to show a student how a spin occurs.

Is there a way to make a paper airplane that will enter a developed spin?


texts: What is the relation between drag and weight?

texts:
Given an aircraft type and fixing its wing configuration (flaps, slats) and fixing its speed and altitude and assuming it flies horizontally, what is the relationship between the aerodynamic drag and weight of the aircraft?

Of course this relationship depends on the aircraft itself and on many other things, but what is more or less the power-law?

Say we compare two A320s, the one heavier by a factor of 1.3. Of course the heavier one will fly with a higher angle of attack, because it needs more lift. This will create more drag and the engines will run with higher power to achieve the same speed. How much more drag will it be? If the behaviour is approximated as power-law, what would be the exponent? The cross section increases when we "pitch" the aircraft. Is the aerodynamics in the design process optimised for "half-loaded" aircrafts? Also, how does this translate to fuel consumption, say on 40000 feet with the usual speeds?


texts: How to calculate the radius of wing tip vortices?

texts: Is it possible to find the radius of wing tip vortices?


texts: What is the diameter of each stage of the PW800 engine compressor and turbine?

texts:
I am an Aerospace Engineering student working to analyze P&WC's PW800 engine family--specifically, the PW814GA, for a project and we need to know some hard-to-find data.
Does anyone knows where I could found out the diameter of each stage of the PW814GA fan, compressor and turbine? Or those of any similar engines so we can guess it? Thanks!


texts: How can I certify an ultralight design as complying with part 103?

texts:
Can you help me about which procedure do I need to follow in order to have a certificate that my design is part 103 ultralight.

And as a information how long would it take to get the certificate and about how much?

What would be the first step?

Thank you.


texts: How close is X-Plane experience to real flying?

texts:
I started using X-Plane and am surprised at the easiness of flying (using a flight controller). Does this simulation software reflect how it is to fly (in any way) in reality?

From using the simulator, I understand that all I need to do is to switch the engines on, turn the brakes off and fly. Are there any additional things apart from a pre-flight checklist that an actual airline pilot has to do?

In addition, I understand that I haven't dove into the details of navigation in X-Plane as I am just wondering if the basics of the simulator software reflect real life conditions.


texts: Would large, low aspect ratio fan/propeller blades be more efficient? Why not?

texts:
With reference to this answer
We read in the above that accelerating a larger mass of air by a smaller amount is (theoretically) more efficient. This is an advantage of a larger propeller than is current practice.
However, we also read above that at some point in increasing size, parasitic drag begins to outweigh the benefits of a larger airmass.
So, what if we used propeller/fan blades with larger surface area, but did not maintain the very high aspect ratios we see today? This would increase Reynolds number, decreasing skin friction drag coefficient. In fact, large-chord fan blades are already being rolled out, though more for simplicity than the above reason.


texts:
I assume that the fuselage and tail fin can generate lift when flying sideways with a constant heading and a little pitch up (er, yaw right assuming left wing down) will introduce a vertical component to the thrust.

Is that all there is?  What else might be going on?


texts: How many African countries currently deploy Cat 3 ILS?

texts: How many countries in Africa currently operate Cat 3 ILS?


texts: Why am I getting unusually high CHT on ground operations on one engine in a Seneca II?

texts: Aircraft had sat for 3 months, and on startup the right engine CHT (Cylinder Head Temperature) was climbing noticeably higher than the left. After taxiing and run up CHT was near top of green. Redline is 460. Other engine readings are normal. Annual inspection completed, mechanic said compression is ok and CHT still in green. I had the probe changed, but the problem persists. During flight, the reading was quite high compared to left engine and compared to what it used to be. What could be the reason for this?


texts: If I get my Private Pilots License before college, how far will that set me ahead, if at all?

texts: So I am looking into getting my PPL and I was wondering if there was any benefit when it comes to college. I am wanting to go to Purdue, preferably, and major in Professional Flight. If I went ahead in getting my PPL now would that get me ahead in college? If it doesn't I don't think it would be worth spending all that money.