# All Questions

14,556 questions
317 views

### What are the consequences of touching down at too low of a speed?

The consequences of a high speed touchdown / high vertical speed are very much obvious. However, what will the consequences be of a low speed touchdown? How severe are they (if any)?
174 views

### Flying coworkers with a commercial pilot's license (USA/FAA)

I will soon have my commercial pilot's license, and work full-time in a company and role unrelated to aviation. As a private pilot under FAA part 61.113b, I know that I can fly myself to conferences ...
151 views

### Can a turbofan engine have less noise so that it doesn't disturb our ears?

A few years back I have seen that Pratt and Whitney 's Geared Turbofan Engine(GTF) has reduced it's noise levels to about 50%. But recently I was having a discussion with a friend and he told me that ...
191 views

Copyright photo by Real Photographs No 334
87 views

### Are landing gear modules interchangeable? [closed]

Are aircraft landing gear modules modular in a way where I would be able to replace the Left Main Landing on one aircraft with the Right Main Landing gear from another aircraft? Or are landing gear ...
85 views

### What are the helicopter frequencies on the LA heli charts used for?

The LA heli charts list frequencies for the different heli routes in LA: Are the frequencies used as a "CTAF" for helicopters, or is there an air traffic controller on that frequency telling ...
107 views

### In normal condition, is the Airbus A320 APU fuel supplied by the main engine boost pump only?

I have a question relating to APU fuel system. As said in material, there are 2 system supplying fuel for APU to operate. 1st one is primary and 2nd one is secondary. In the 1st system or low ...
8k views

### Do all aircraft carry depleted uranium as counterweights?

I was told that most aircraft had depleted uranium on board as counterweights. I have not seen one myself. Do all current modern aircraft have depleted uranium on board?
7k views

### Was the Space Shuttle aerodynamically neutral while piggybacking, or did the combination act like a giant biplane?

Trying to investigate this question, I see that 'Ask the Captain' says: The weight of the shuttle is calculated like any payload. The 747 produces enough lift to fly and to carry the weight of ...
66 views

### Gas Turbine engine inlet [closed]

I understand that the turbine of the engine runs the compressor and the fan of the engine. If the air flows through the compressor undisturbed, can we avoid having an inlet in the gas turbine engine ...
341 views

### How close to the White House did the Space Shuttle Discovery “fly”?

The CNN article For 747, transporting a shuttle is no heavy burden shows the shuttle Discovery on top of a "shuttle shuttle", a special 747 used to shuttle the space shuttles around. How close to the ...
58 views

### How can I calculate the velocity of air drawn by a pusher configured propeller?

I am attempting to construct a model plane using Custer channel wings. In order to calculate (or at least approximate) the lift generated I need to find the speed of the air through the channel due to ...
83 views

### Need more volume with my aviation headset (David Clark OneX). I wear hearing aids

Does anyone know of a way to get more volume out of my David ClarK ANR aviation headset. I wear hearing aids and often fly in older airplanes with older radios that are scratch/weak/etc. I select ...
243 views

### Is it legal for pilots to transport or use marijuana?

More and more states are legalizing the recreational use of marijuana. What does that mean for pilots? Is it legal for pilots to transport marijuana within states that have legalized it? Can pilots ...
173 views

### How do dry bays protect against fire?

How do dry bays protect against fire, and do civil aircraft also have dry bays like military aircraft?
232 views

### How many private jets land at Heathrow airport per day?

Heathrow airport is one of the busiest airports in the world, one would assume most traffic there is reserved for commercial airliners because they carry a much larger number of passengers. How many ...
132 views

### Why is the weather radar mounted on the left wing of the TBM?

Weather radar is mounted starboard on the Pilatus PC12 or in the Piper Meridian/M600/M500. It adds drag to the right wing, thus a right yawing moment, and helps to counteract the slipstream effect ...
216 views

### Is there a practical carbon-free jet fuel?

For example, when I want to use a small turbojet or low bypass turbofan as both the APU and bleed air supplier for blown flaps, ailerons, elevators, (like the ShinMaywa US-2 amphibious plane) and ...
227 views

### What is this white-tail, short upper deck 747 I just saw?

It was seen taking off from a US Air Force base, which is part of Air Mobility Command. A great deal of their operation is departing or returning troops from abroad, so it gets a lot of rare visits ...
75 views

### Do any aircraft have liquid-cooled brakes?

Aircraft wheelbrakes, especially those on heavy aircraft, get really, really hot during landings and rejected takeoffs, and cool down very, very slowly without active cooling. This imposes limits on ...
142 views

### What do these ramp markings mean at KIFP?

As a pilot, what do I need to know about these ramp markings at KIFP? Are they operationally significant?
28 views

### Will Thrust on Rotor (Main) increase with altitude?

Can some one please let me know,if the thrust required on the rotor head increases with the increase in altitude in an Helicopter or decreases with increase in Altitude?. Thanks in advance, Pawan
187 views

### What is the naming convention for European airways?

I know that in the U.S. low altitude airways are called Victor (below 18.000ft, e.g. V123) and high altitude routes are called Jet (above 18.000ft,e.g. J123). Can somebody explain the European ...
55 views

### E class airspace(transition area)

Extension area(E airspace) shown as shaded magenta start from 700AGL but how to measure 700AGL over the water like in this picture? Cuz there’s no land…
64 views

### Gyro Erection System

I have a hard time understanding the physics behind the pneumatic erecting system in an attitude indicator. According to my book and the linked image, the applied force is “precessed 90 degrees” (anti-...
1k views

### What is that CFM56 with a toothed exhaust on an A321?

I stumbled upon a wikimedia picture and I saw something that I have not seen before: a CFM56 with a toothed engine exhaust. Can someone explain to me what engine variant that is? Source Author: ...
198 views

### Can you be a pilot after being diagnosed with Generalized Anxiety Disorder?

Went to my primary care physician who referred me to the psychologist. Went in for two evaluations. The only thing that had been written on my medical record was anxiety, no medications of any sort ...
92 views

### Can we change light aircraft skin from aluminum to foam and fiberglass? [closed]

Can we change the skin and wings of light aircraft from aluminum to foam and fiberglass composite in zenith ch 750 ?
136 views

### Positions of drag wires in a bay

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 ...
3k views

### Can hydrogen gas be an alternative fuel source for a gas turbine engine?

I want to do research for an alternative fuel source for a commercial aircraft that will reduce the cost for flights. Will the hydrogen gas be ignited in the combustion chamber and produce enough ...
245 views

### Why was the 737 main rudder servo valve’s vulnerability to causing uncommanded reversals never discovered in testing?

As was discovered during the NTSB investigation into the crash of USAir Flight 427, the design of the servo valve inside the main rudder power control unit (PCU) formerly used on 737 Original- and ...
962 views

### How do I keep a C172 straight on the centerline during landing/rollout?

During rollout upon touching down, I'd often find myself veering off the runway centreline to the left. Every time I input rudder, I have this feeling that I am getting pulled out of the turn (while ...
98 views

### What is the aircraft in the 'Be Altitude' album cover?

In 1972, the Staple Singers released the "Be Altitude" album, which has them posing in a jet engine's intake. My question is what aircraft does that engine belong to? And why would someone let them ...
242 views

### Are modern fighter jets bulletproof and armored?

Are modern fighter jets bulletproof and armored? One would not be wrong given part of their operations is being on the receiving end of enemy ammunition shooting at them.
127 views

### What material is used for the skin of a modern fighter jet?

Modern passenger jets/airliners use aluminum 2 to 3 mm thick as their skin, their maximum speed is 900 km/h give or take. Modern passenger fighter jets travel at twice that speed on average. What ...
172 views

### Why do planes above FL290 need more vertical spacing?

At altitudes no higher than 29,000 feet, planes need only 1,000 feet of vertical separation. However, planes over FL290 need twice that, i.e. they need 2,000 feet of vertical spacing between them and ...
753 views

### Are centrifugal turbojets easier to make than axial ones?

Looking at the history of jet engines, I noticed that the British first made centrifugal-types, but the Germans went straight into axial-types. Which type is easier, if any? By that I mean, which ...
58 views

### How are these parameters derived from readings of sensors in an aircraft: angle of attack, slip angle, and airspeed?

From what I've learned, the reading comes from an angle of attack sensor and a slip angle sensor. Let's call the readings $\hat\alpha$ and $\hat\beta$ respectively. These are of either the ...
88 views

### Why are the positions of an aircraft's angle-of-attack vanes dependent on airspeed?

According to this answer to an earlier question of mine, the positions of the angle-of-attack sensor vanes on the A330/A340 are dependent not only on AoA, but also on airspeed (and, according to @ymb1'...
151 views

### Which one needs longer runway of an airplane between take off and landing for a constant weight?

Consider we have an airplane that the weight will be constant when take off and landing (in fact will be no such common airplane right now as the fuel will be less due to engine consumption. But in an ...
180 views

### ATC calling out regional airlines in traffic advisories: phoenetic or “aircraft paint” airline used?

When ATC points out traffic that is a regional airline (e.g. Compass, Envoy, SkyWest, etc.), do they use the phonetic callsign of the airline, or do they use the callsign of the airline that they are ...
220 views

### Who manages air traffic during Red Bull air races?

I'll preface this by saying I'm not a pilot so I don't know much about Air Traffic Control. How does Air Traffic Control work for Red Bull air races? Does: (1) each plane taking off need to contact ...
147 views

### How safe are sail planes? [closed]

I think sailplanes have to be pretty safe. Because if it falls it will gain speed, which will be converted to lift. So unless you do something stupid sailplanes can't just fall out of air. Am I ...
143 views

### How did shortening the 707 increase its range?

According to the Wikipedia entry for the 707-120: The 707-138 was a −120 with a fuselage 10 ft (3.0 m) shorter than the others, with 5 ft (1.5 m) (three frames) removed ahead and behind the wing, ...
5k views

### Can you help me identify a vintage airplane in a painting?

This is a recent photo of the king of Spain, Felipe VI, visiting Spanish troops stationed in Iraq. In the background there is a picture of an old plane, possibly with a propeller, that I suppose from ...
55 views

### Which airspace requires what RNP?

How do I know which airspace requires what RNP value? More specifically, can I go from NY to London with just BRNAV providing I stay above the NAT HLA?
170 views

### How is the F-22's nacelle/engine bay ventilated?

How is the aircraft skin around engine bay in F 22 is being cooled? As in F 35 there are scoop below the wings which provide ram air around the engine bay, but you don't see any scoop around in the F ...
44 views

### Meaning of XX below Slat FLap Trim on A350 with flap setting 1

What is the meaning of the 'XX' in amber below the 1 (in green) within the Slat Flap Trim section on the A350 PFD when the flaps are set to 1 with the correct speed (below 255kts)? See picture ...