All Questions
24,975
questions
2
votes
1
answer
114
views
Does the pressure recovery on the rear side of an airfoil recover all of the pressure?
I was wondering if all of the low pressure created by the airfoil gets recovered on the rear side of the wing. (I know during a stall or flow separation, this doesn’t happen, I think)
My main question ...
- 435
0
votes
1
answer
186
views
What is the history life of Cessna 172 airplane?
How can i find manufacture date of cessna 172P knowing serial number?
- 1
2
votes
3
answers
483
views
How do you find the center of gravity of an Anthropomorphic Test Device
In regards to the aircraft seat testing process in which the occupant's center of gravity is required, I am quite interested to know how people calculate the C.G. of an Anthropomorphic Test Device (...
- 19
1
vote
2
answers
88
views
Type of airfoil used by Briggs, Hull, and Dryden
What airfoil do Briggs, Hull, and Dryden use in NACA Report No. 207: https://ntrs.nasa.gov/api/citations/19930091273/downloads/19930091273.pdf
They mention it a few times:
"The airfoils tested ...
- 111
1
vote
0
answers
66
views
Is there any public available documentation about Honeywell FHDB files?
I am new to aviation, my task is to read FHDB (Honeywell Fault History Data Base) files.
They seem to be kind of tab separated values but with special bytes at line start.
like: ...
- 111
1
vote
0
answers
91
views
How does more lift help during a stall (ex. flaps deployed) [duplicate]
How does more lift help in a stall? For flaps, I thought the effective increase in camber of the wing would make the wing have a higher AoA, therefore making a stall happen sooner.
Thanks!
- 435
18
votes
2
answers
9k
views
What is this little "rod" thing on the back of the F-22 for?
I was curious what this little extra surface on the back of the F-22 is for. I can't see any use of it protruding past the engine nozzles, so what is it for?
- 435
1
vote
1
answer
81
views
Static port and drain hole blocked with pitot tube unobstructed
In this situation, would pitot-static instrumentation behave as if only the static port was blocked? What about if only the drain hole becomes blocked?
Thank you
- 121
10
votes
6
answers
3k
views
Function of the compressor in a gas turbine engine
I am trying to understand the importance of having compressed air in the combustion chamber of a gas turbine engine. As far as I understand it, the reasons are twofold.
Firstly, the compressor is ...
- 103
-2
votes
1
answer
287
views
Here's another German aircraft of unknown descent?
A most unusual all-white single-engine pusher tri-plane
- 509
1
vote
1
answer
257
views
2
votes
1
answer
105
views
Why does a helicopter that uses the Coandă effect need a direct jet thuster aswell
Why does a helicopter that uses the Coandă effect instead of a tail rotor need a direct jet thruster as well. Why couldn't they just vary the pitch of the ducted fan used for the Coandă effect?
- 313
0
votes
1
answer
51
views
Why are there different bracket shapes to Class D airspace?
A Class D airspace ceiling is typically depicted with a two digit number surrounded by four brackets depicted below.
Why do some Class D airspaces have the same four brackets, with four additional ...
4
votes
1
answer
223
views
Lateral balance of single aisle planes with odd numbers of seats in each row [duplicate]
Do single aisle passenger planes with an expected odd number of seats in each row (e.g. 2-3, 1-2) where the aisle ends up not being central adjust the design of the plane overall to account for this ...
- 151
0
votes
2
answers
75
views
Are UDF/Propfan Engines Thrust Producing or Power Producing? [duplicate]
For the purposes of aircraft performance (best endurance/range speeds, Vx, Vy, etc.) would a propfan be considered a power producing engine or a thrust producing engine?
I would imagine it would be ...
1
vote
1
answer
117
views
Hypothesis: swept back propeller would reduce drag and increase thrust [duplicate]
Hypothesis: swept back propeller would reduce drag and increase thrust. Any experience with this?
- 13
2
votes
1
answer
645
views
What are FAA rules regarding FBO operations encouraging food/ refreshments for pilots?
Specifically chapter, section, paragraph relating to food services for private pilots at an FBO.
- 29
2
votes
1
answer
152
views
What is the name of the area, controls and instruments where a loadmaster sits?
In a HLA (such as an Antonov, C5M, or C17 Globemaster III), what is the name of the area where the loadmaster sits?
Also, what are the names of the controls and instruments that the loadmaster uses ...
- 21
2
votes
2
answers
353
views
Are Light Sport Aircraft: Certified, Experimental or a third separate category?
Is a Light Sport aircraft considered to be A certified or experimental aircraft? or is Light Sport a completely different third category?
- 5,732
0
votes
0
answers
61
views
Incidence angle in Sailplane
I am determining the shape of the fuselage of a sailplane and I found something that gives me a little conflict, and that is that in most sailplanes it has an inclined tip, I read that this helps ...
- 113
1
vote
0
answers
197
views
DO-178 qualified source code obfuscation
I want to to perform obfuscation on the software that will be delivered the customer as a library or executable to prevent or at least make it difficult to de-compile the product. However some levels ...
- 53
12
votes
4
answers
2k
views
How does a helicopter rotor keep spinning in the same direction when autorotating without reversing the pitch
I have read that if helicopter's engine fails, you set the pitch to minimum but not reverse pitch. The rotor would have to be tilted back to provide an angle of attack on the blades so it glides like ...
- 313
4
votes
1
answer
141
views
What are the modulation parameters of a DME?
I am having difficulties finding specific information about DME pulse pair modulation. As far as I understand, the gaussian shaped pulse pairs are modulated using amplitude modulation. The carrier ...
- 43
0
votes
0
answers
80
views
Chord Wise Load Distribution
I'm looking for some guidance on how to compute the chord-wise lift distribution of the wing using Xflr5 or OpenVsp or any analytical method. This is for designing the internal structure of the wing.
...
2
votes
1
answer
194
views
Localizer beam protection
During mixed operation, will an aircraft crossing the end of the runway affect the localizer transmission?
(Istanbul airport, source.)
For instance, when runway 17L is in use, will an aircraft ...
- 59
26
votes
1
answer
4k
views
Can you help identify this vintage aircraft?
Please help identify this aircraft. Photo taken in Rijeka, Croatia early 1900s
- 263
-1
votes
1
answer
238
views
How would a GE9X's react to ingesting a person?
Was wondering how a GE9X (or GE90/etc.) would fare after ingesting a person, at takeoff or climb thrust. (For a story.) Obviously the person is dead and the engine can safely be assumed to be a write ...
- 21
0
votes
1
answer
194
views
Are there studies to find surface treatments to reduce the drag of an airfoil?
I know that by designing an airplane or a car close to a teardrop, we can reduce the drag. My question has to do with the surface friction treatment. Some torpedoes glide in water more efficiently ...
- 995
4
votes
2
answers
197
views
Why does the turn tighten in a Spiral Dive as it progresses? Even without applying any elevator control?
Why does the turn keeps getting tighter as the spiral dive develops?
Use of elevator control makes sense as it would increase the horizontal lift vector inside the turn. But even without any elevator ...
- 609
4
votes
3
answers
4k
views
Lighter than air vs heavier than air?
I know that hydrogen balloon is an example of lighter than air aircraft while today aircraft like helicopters and Boeing 747 are examples of heavier than air aircraft.
But I want to know about more ...
- 49
0
votes
0
answers
134
views
How exactly does the startup vortex form, and why does it occur when circulation around the wing changes?
So I was wondering how exactly the startup vortex forms, why it dissipates, and where it's located in relation to the trailing edge of the wing. Also, why does a startup vortex form when circulation ...
- 435
0
votes
0
answers
94
views
Is there any API for planes with ICAO identifiers?
I'm looking for an API that I can use for images and details of all planes, preferably searched by the name of the plane or the ICAO identifier of the plane.
Right now, I've found a list on Wikipedia ...
- 315
2
votes
1
answer
163
views
For a fixed density altitude, how does climb performance depend on pressure altitude?
Below is the climb performance from the 1978 Cessna 152 POH, which I've plotted as climb rate versus density altitude. It shows that higher pressure altitude gives decreased performance even when the ...
- 12k
1
vote
1
answer
84
views
Are crosswind corrections during taildragger taxiing the same as with tricycle gear?
When doing crosswind corrections during taxiing with a tail dragger, is it the same with the tricycle gear or not?
Confused with the elevator part.
- 81
3
votes
3
answers
897
views
Taxiing with a crosswind
Let us say we have a right quartering headwind, we should “fly into the wind” so yoke to the right then that our right aileron will deflect up and left aileron down. How does this avoid the chances of ...
- 81
0
votes
0
answers
54
views
Deriving Accurate Exit air velocity of rotor
My goal is to derive the equation for exit air velocity as a function of:
Pitch angle
RPM
Rotor Radius
Constants like ρ
Assumptions:
Vc is relative velocity of air upstream, and is = 0
Inflow is ...
-1
votes
0
answers
173
views
Why are only flaps 5,10,15 recommended in windshear operations during B737-800 takeoff?
During takeoff in a B737-800 when there is predicted wind shear you can only use flaps 5,10 and 15.
Why is this? If possible to provide a reference for it.
- 81
-1
votes
1
answer
102
views
Cessna 150 Battery master switches off when ignition switched on
We have a Cessna 150 with an electrical fault. When you switch the ignigtion switch to the both magneto position, electrical power is lost. Switch the ignition switch back to either the left or right ...
- 1
4
votes
1
answer
220
views
Can new thermals be generated above a cloud layer?
Thermals rise from the ground due to uneven heating from the sun, then stop rising once they start condensing into clouds. My question is can new thermals be formed at the top of this cloud layer? I ...
- 43
3
votes
0
answers
106
views
What legacy turbojet would have detailed documentation and drawings available for free or cheap?
I am fascinated by the technology of jet engines. As a hobby, I might like to create a detailed animated 3D model of one (and publish it with a Creative Commons license). Obviously I am not going to ...
- 746
8
votes
4
answers
2k
views
Why do you land a fighter jet with AOA Units?
I currently begann learning Falcon BMS and watched some fighter cockpit landings on YT and learned the technique to land a fighter is to use your AOA and not Airspeed like you would do it on a GA ...
- 81
0
votes
0
answers
75
views
Why does Aerodynamic Center move to 50% chord when supersonic?
There are several sources available that state that when an airfoil is fully supersonic, the Aerodynamic Center will move to the 50% chord location. Some of these sources, the ANA shown above being ...
0
votes
1
answer
55
views
Can composite material be used in leading edge of airfoil instead of aluminium through Additive manufacturing?
I want to know about, is it possible to replace aluminium by additively manufactured leading edge of airfoil by changing different infill patterns to improve the impct strength from bird impact on it.
2
votes
1
answer
193
views
Where are some of the most challenging airfields in the UK?
I fly Microlights and am used to short strips, I can land at airfields such as Brown Shutters and Clench Common without much strain.
What are some of the most challenging airfields in the UK for light ...
- 12.5k
0
votes
1
answer
174
views
what speed was the "negative 4G inverted dive" in Top Gun
I realise that the "negative 4G inverted dive" described in Top Gun is a hypothetical manoeuvre, but I was wondering what sort of speed they would be flying at. I'm guessing low subsonic ...
- 1
3
votes
2
answers
263
views
Is blade flapping "fully automatic"?
I have a rather simple question just to "double check" if I understood blade flapping right. So, I understand that a helicopter, in forward flight faces an asymmetric lift. Blade flapping is ...
- 173
3
votes
1
answer
231
views
What is the reason for aircraft AC power supply neutral wire not connected to chassis GND?
In home utility power supply, AC neutral and earth GND are connected together at distribution transformer output.
Is there a reason why aircraft power supply is not following the same practice? Why ...
- 545
1
vote
1
answer
96
views
Will accidentally using 1 quart of non-mineral oil during engine break in cause engine damage or lead to increased wear in the future?
One of the aircraft I rent is a Piper Warrior (PA-28) with a Lycoming O-320-D2A. I accidentally put regular oil in it today rather than mineral oil. The engine had run 20 or so hours since its ...
- 121
1
vote
1
answer
100
views
What's the fastest atmospheric missle that demonstrated a useable radome?
I read that
DoD has stated that its hypersonic boost-glide missiles will be able to emit and receive radio signals, such as those from the Global Positioning System (GPS). That statement implies that ...
- 518
0
votes
1
answer
76
views
How to find TAS, IAS, PPH and USG?
Could somebody explain this task. I do not understand how to use this table :(
- 11