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1 answer
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How to calculcute variation and compass deviation in this CDMVT problem?

Usually I can solve CDMVT problems, but sometimes I feel I'm missing something important. For example: I'm able to solve: Given WCA -012, TH 125, MC 139, DEV 002E. What are TC, MH and CH? ...
Mandal Vomva's user avatar
0 votes
1 answer
98 views

Why are shockwaves allowed different angles at different distances from a body?

It's been (well) established that a shockwave can only be at the angle of the Mach cone. (I now understand this part). However, in this picture: you can see that the shock is at 2 angles. I also ...
Wyatt's user avatar
  • 2,676
0 votes
0 answers
36 views

Are the spring constant and damping coefficient of landing gear publicly available?

I'm trying to find the spring constant and damping coefficient for a Cessna 172. I looked through the POH, but couldn't find them anywhere. Are these values available publicly in some design document ...
cph2117's user avatar
  • 245
3 votes
1 answer
252 views

Dyke Delta dynamics?

I recently came across the Dyke Delta, designed by John Dyke. It is a delta wing (more like diamond planform) homebuilt. I'm curious about how this airplane handles, considering delta wings have some ...
Slick Tires's user avatar
0 votes
2 answers
56 views

Why will a slower moving parcel of air above a wing create drag in non-inviscid flow?

This answer explains why a thicker boundary layer will cause a type of form drag. It uses inviscid flow to explain this. It is a great answer, but I can't seem to see how this applies in a real world ...
Wyatt's user avatar
  • 2,676
3 votes
1 answer
150 views

What percentage of airliners today operate with unaugmented GPS equipment?

Responding to this question there was some discussion on GPS equipment and whether it used augmentation (WAAS/SBAS/GBAS) or not. What percentage of airliners operate with unaugmented GPS equipment? ...
Pilothead's user avatar
  • 20.7k
4 votes
2 answers
140 views

ILS Designated Operational Coverage (DOC)

During a standard Instrument Landing System (ILS) approach, I typically arm the VOR/LOC (Boeing 737) to capture the localiser1 once on an intercept course. Upon clearance for the approach, I then arm ...
tedioustortoise's user avatar
1 vote
4 answers
308 views

How do the landing gear support so much mass?

The first thing that one notices after seeing an aircraft, is that it's quite a heavy flying machine. And so, one would expect monumental tires on these vehicles, yet they don't exist. How is it that ...
Aerospace_Nerd's user avatar
1 vote
1 answer
169 views

How are military aviators call signs made?

Military aviators always have a call sign that they are referred to as. I would like to know how they are picked? Is it their personality, surname or what?
James Bolus's user avatar
22 votes
2 answers
5k views

Why do airplanes sometimes turn more than 180 degrees after takeoff?

Why do sometimes (at least in commercial flights) airplanes do a more-than-180-degrees loop after takeoff, in order to aim at the target direction? See image for an example. I guess that it is part of ...
Riccardo Ceccon's user avatar
10 votes
1 answer
158 views

Is there any version of CFM56 with can combustors?

This lamp is sold online: They claim it's made from a CFM56 combustion chamber. It looks like a can combustor, and I read everywhere that CFM56 uses an annular combustor. Is there a version of CFM56 ...
Evariste's user avatar
  • 203
4 votes
1 answer
350 views

Which underwater crash sites of medium to large aircraft have been captured in sonar imagery?

For which crash sites of medium to large aircraft are sonar images available ? Scope: The crash site should already be confirmed (not speculated). For the purpose of this question, let's define "...
summerrain's user avatar
  • 3,474
1 vote
0 answers
90 views

Twin engine or single engine with parachute, which is safer?

Statistically speaking, if we compare two airplanes: a twin engine (like the Beechcraft Baron) VS a single engine with a parachute (like the Cirrus SR22), if we add up all posible emergency events(...
Gabe's user avatar
  • 3,337
3 votes
1 answer
87 views

Flying N-registered Aircraft in the EU (as an EU resident)

Until recently, I believed what the old, wise men of my local flying club had been telling me for years: You can fly N-registered aircraft in Europe... as long as you have an FAA license. I recently ...
Wasserwaage's user avatar
  • 1,704
2 votes
1 answer
62 views

How does a thickening boundary layer create form drag?

Imagine a normal wing with flow over it, and to simplify things it's at 0 AoA. Drag is being made mainly because of form drag and skin friction drag. I'm not sure on this, but I don't think there ...
Wyatt's user avatar
  • 2,676
3 votes
2 answers
166 views

A question on stalling and flat spin - in gliders

Very short version: Do gliders do stalls, and flat spins, as aerobatic tricks (as do say aerobatic biplanes). -- As I understand it, with an aerobatic plane, a pilot can and does, for "fun" ...
Fattie's user avatar
  • 1,932
3 votes
1 answer
154 views

What's the precision difference between ILS and GPS(LNAV/VNAV)?

What is the precision/accuracy difference between both GPS (LNAV/VNAV) and ILS?
Gabe's user avatar
  • 3,337
21 votes
1 answer
3k views

Vintage photo, Seatac airport

I’m spending the night in a hotel at Seatac Airport in Seattle, Washington, USA. The vintage photo below is hanging on the wall of my room. I recognize the airport as Seatac, circa 1950’s. The photo ...
Stu Smith's user avatar
  • 521
5 votes
1 answer
151 views

How did the Concorde’s glide ratio vary from takeoff to supercruise?

I can't seem to get straight numbers on its glide ratio. One source claims 4:1 at takeoff and 12:1 at transonic speeds. But what about the supercruising phase that it's flight was optimized for?
Kevin Kostlan's user avatar
6 votes
4 answers
2k views

How do planes deal with excess lift at high speeds?

If I understand correctly, wind force increases quadratically as airspeed increases. Therefore, all other things being equal, lift should also increase quadratically. Does that mean, a plane going ...
CaptainCodeman's user avatar
3 votes
1 answer
182 views

What limits automated direction finding from working over oceans?

Automated direction finders are only reliable in relative close proximity to NDBs, due to various adverse effects. In particular, the night effect limits their useful range for navigation ...
lxgr's user avatar
  • 261
5 votes
2 answers
114 views

Do vtails need twin horizontal trim tabs?

Do vtails need twin horizontal trim tabs? As vtail aircraft don't have a separate horizontal tail, do they need a trim tab on both rudervators?
Fred's user avatar
  • 1,393
7 votes
1 answer
2k views

Was radio navigation used for oceanic crossings before GPS? If not, why not?

As far as I understand, before the availability of GPS and other GNSSes, airplanes crossing large distances over water, beyond the range of ground-based navigation aids such as VORs and NDBs, largely ...
lxgr's user avatar
  • 261
-2 votes
1 answer
125 views

How does the air molecules provide wing lift force when only wing is moving or when only the air is moving?

We use to calculate lift force of a wing as function of air speed squared. We can imagine 2 different situations: 1 - the wind has speed thus kinetic energy and momentum while the wing is stationary 2-...
user avatar
0 votes
2 answers
99 views

How do you communicate with atc and how can they communicate with you when you change frequency?

How do you let atc know that you are going to a different frequency and how will you be able to talk to them if they need to talk to you will they go to that frequency that you went to?
User9993454's user avatar
-3 votes
1 answer
132 views

What's gonna be the physics behind building 'futuristic' airplanes? Use physics formulas or even theories to answer this question [closed]

After thinking about these 'futuristic' airplanes, I wonder if there's any special physics theory or law behind them. I wonder how faster they can be, persevere more and fulfill the aviation's lover ...
Aviation Club Aviators's user avatar
0 votes
1 answer
162 views

What aircraft used this compass?

I was wondering if anyone had any info on this compass I have.
Atropine242's user avatar
1 vote
0 answers
154 views

Why don’t closed wings eliminate tip vortices?

It’s clear that tip vortices never really can be prevented, but why doesn’t a closed wing do that? There is no ‘tip’ on a closed wing so where does the air go to make a vortex? On a normal plane the ...
Wyatt's user avatar
  • 2,676
1 vote
1 answer
153 views

What frequencies can you freely speak on? [duplicate]

Are there any frequencies that you can use to communicate with your family at home when you are flying and for a wokie talkie I am wondering if there are just any frequencies that you can speak freely ...
User9993454's user avatar
13 votes
2 answers
6k views

Is it possible to tell what aircraft this is?

On a flight a few years ago, I got this picture. Is it possible to tell the aircraft by just this image? I’ve found a few similar but they are a bit different than this one. Someone I was with said ...
Wyatt's user avatar
  • 2,676
6 votes
2 answers
189 views

When ATC tells you to climb or descent now, do the speed restrictions on SIDs and STARs still apply? (EASA)

I am flying the ELSUP 1H departure. After taking off, I get told to climb to FL100. Do I have to comply with the speed restrictions? Is it the same for a STAR?
standel's user avatar
  • 63
-1 votes
1 answer
257 views

Why would the F-16 pilots chasing Flight 93 on 9/11 have needed to ram the airliner?

I realize that this is an old topic, and some elements seem to have been answered in the question below. However, one of the two F-16 pilots who scrambled to intercept United 93 just retired from the ...
ProfessorE's user avatar
1 vote
2 answers
100 views

How to determine dihedral angle?

How to determine dihedral angle for a high wing ga aircraft with 12' wing span? While there are formulas for determining size of the vertical and horizontal tails, I have yet to find a simple formula ...
Fred's user avatar
  • 1,393
0 votes
0 answers
33 views

What is the size of a clam shell drag rudder compared to a conventional rudder?

What is the size of a clam shell drag rudder compared to a conventional rudder? This is for a ga aircraft.
Fred's user avatar
  • 1,393
1 vote
1 answer
96 views

Why does the Varieze need a metal wing connector?

Why does the Varieze need a metal wing connector? If the Varieze has Fibreglass wings and a center spar, why is the connector made of cast metal?
Fred's user avatar
  • 1,393
2 votes
1 answer
233 views

Do airline pilots prepare and are aware of possible emergency landing sites around airports they are taking off in case of complete engine failure?

Do airline pilots prepare and are aware of possible emergency landing sites (like farm fields, wide highways, lakes etc.) around airports they are taking off in case of complete engine failure at a ...
MangoPanda21's user avatar
4 votes
1 answer
141 views

How are cockpit warning sounds recorded/chosen?

I know that during an emergency, sounds in a cockpit such as "TERRAIN PULL UP" are played or in some planes the stick shaker takes place during a stall. But how are such warning sounds and ...
Aerospace_Nerd's user avatar
7 votes
1 answer
1k views

Gap between F22 ailerons and flaperons

You can see in the below picture that there's an F22 on approach (I think) and this is almost a perfect bottom view of the plane while it's going straight, it isn't banking. There's gaps between the ...
Aadiraj Anil's user avatar
3 votes
2 answers
96 views

Lateral Stability- Why aircraft will not return of its own accord to the original heading after a sideway gust?

I am reading the Stability section of FAA it says: If an aircraft is flying in a straight line, and a sideward gust of air gives the aircraft a slight rotation about its vertical axis (i.e., the ...
Flying777's user avatar
1 vote
1 answer
93 views

why does the bottom of a 737 - 800 engine look slightly flat? [duplicate]

The 737 - 800 is one of my favorite airliners and so I've always noticed that it's engines look a bit flat on the bottom, I haven't seen any other airliners do this so, is there any specific reason ...
Aerospace_Nerd's user avatar
-1 votes
1 answer
48 views

Density altitude difference (formula and Asa CX-3)

I am trying to figure out Density Altitude problem from the book and I get one answer by hand and another with CX-3 and cannot find the bug. So problem goes like this, Indicated Altitude 5250 feet ...
user505160's user avatar
0 votes
1 answer
49 views

Why will the flow turning angle be 0 (or close to) inside of the Mach cone?

(Disclaimer : This probably seems like my 56th question on the same topic, but this will be my last relating to Mach cone angle and shock angles, as I think I understand most of the topic) So the ...
Wyatt's user avatar
  • 2,676
-1 votes
1 answer
159 views

Circling aircraft [closed]

Hi guys I'm a newbie here, so apologise if this has already been answered. I'm in The UK and since 2020 RAF aircraft have been circling my city, and have noticed after that it is happening in other ...
YorkshireRover's user avatar
1 vote
1 answer
53 views

Why are some of the boxes with VOR information thick (like IST VOR) but some of the boxes are thin (like UHM VOR)?

Why are some of the boxes with VOR information thick (like IST VOR) but some of the boxes are thin (like UHM VOR)?
pilot162's user avatar
  • 2,217
1 vote
2 answers
108 views

If sweep angles are high enough can supersonic wings use thick, rounded airfoils?

In lectures on aerodynamics, it's always emphasized that the effect of sweep is to lower the Mach number normal to the leading edge. In the context of supersonic flow, this ensure that the leading ...
interested22's user avatar
0 votes
2 answers
122 views

Meaning of “G” in aviation [duplicate]

The Singapore Ministry of Transport just published the preliminary report for SQ flight 321 yesterday (https://www.mot.gov.sg/news/details/transport-safety-investigation-bureau-preliminary-...
Kim Leung's user avatar
6 votes
4 answers
3k views

What is a "rapid changes in gravitational force"

I've been reading an article on the BBC Website about the 21/May/2024 incident on Singapore Airlines. According to this article: "The rapid changes in G over the 4.6 seconds duration resulted in ...
Stormcloud's user avatar
4 votes
2 answers
263 views

How does rudder braking work? [duplicate]

I've always been unable to understand how rudder braking/toe braking works and how you steer while using rudder braking. Hence I came to this website with possibly the most knowledgeable people I ...
Aerospace_Nerd's user avatar
5 votes
2 answers
195 views

Could a propeller system for airplanes with automatic, cyclic blade-pitch control that is designed to counter p-factor be practical?

Considering that P-factor is a result of differing angles of attack of the blades on an airplane's propeller, I would imagine that if there was a design that could control the pitch of each individual ...
Ryan Mortensen's user avatar
3 votes
2 answers
678 views

What if the onboard airspeed sensors fail? [closed]

I've a simple question regarding the rare case of the failure of all airspeed indicators (ASI) including the co-pilots's indicator. Say the airspeed indicators were to fail during rotation, what would ...
Aerospace_Nerd's user avatar

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