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Why does the U.S. have so many general-aviation aircraft? In a comment on my previous question about the paucity of South Korean general-aviation aircraft in the 1990s, @Pondlife pointed out (in response to my comparison between the numbers of GA aircraft per capita in South Korea and the United States) that, in the...	The USA is a wealthy country that has been that way since the invention of flight. In addition, gasoline is much less expensive here than in western Europe so the operating costs will be lower.
Has there ever been an airliner design involving reducing generator load by installing solar panels? Has there ever been a trial/project/design, in which solar panels were incorporated in the design of a commerical airliner (e.g. on the wings), with the aim to reduce fuel consumption by lowering the generator workload?...	Solar supported airliner isn't out of the realm of possibilities, just solar tech isn't there yet.
What is the meaning of "Steer 1-2-0" in WWII texts? I am reading some texts about WWII and English operators tell the pilots to "Steer 1-2-0". Can anyone help with the meaning of 'steer' here? Is it a synonym of 'direction', 'heading' or 'vector'? <Q> To "steer" means to change the aircraft's track (the direction of mo...	to steer ' = 'to change course to', and the number is a compass heading.
What is the offset in a seaplane's hull? I noticed there is a little offset in a seaplane's hull (highlighted in the following picture). I suppose this is useful as it exists in all the seaplanes I know. It appears to be neither a hydrodynamic nor aerodynamic feature. I could not find clue by myself as I don't know ...	That's called the step .
Do airline pilots ever risk not hearing communication directed to them specifically, from traffic controllers? I gather pilots communicate regularly with air traffic controllers within air traffic controllers' jurisdiction or airspace as they enter the space, during their time in that space and as they leave. In some ...	Normally pilots do not communicate much with ATCC between airports. Obviously, if a commercial crew with a lot of passengers goes unresponsive for so long that it requires an intercept, they are going to get in trouble.
Why isn't airport relocation done gradually? Recently Istanbul airport (IST) was relocated from Atatürk over 2 days. Munich Franz Josef Strauss (MUC) was also moved overnight from Munich Riem . Doesn't it cause chaos, since most employees are new to the place and equipment, work procedures are not well establish...	Gradually moving between airports is a living nightmare for connecting travelers.
Does an rc plane tail also have airfoil or is it just flat material? I've chosen an airfoil for the wing, now i'm confused weather i should do the same for tail or just attach a flat piece of wood as tail. I'm going for conventional tail design.This is my first ever plane so sorry for the dumb question. <Q> A flat piec...	The tail's job of producing downforce doesn't require the lift coefficients or angle of attack range required of the main wing, so the actual airfoil shape is not that important especially at low speeds, even more so under the low Reynolds numbers ("thick" air) that RC airplanes work at.
Why doesn't Stratolaunch have connected tailplanes like it has connected wings? As a complete layman, the design of the Stratolaunch airplane, especially when reminding myself of its size, seems too flimsy, in that the only connection between the two fuselages is the center wing. Apart from apparently trusting their ma...	It's inefficient from the payload perspective (the payload, be it live or cargo, prefers one big tube), but the Stratolaunch carries its payload slung between the twin fuselages.
When communicating altitude with a '9' in it, should it be pronounced "nine hundred" or "niner hundred"? It sounds a little odd, but trying to understand if that's the recommended way to communicate. E.g. 9900"Nine-thousand-nine-hundred"vs"Niner-thousand-niner-hundred" <Q> In the UK, the RT rules for the ANO are in ...	In the US, NINER THOUSAND is used by most pilots, but you'll hear NINE occasionally.
Can a drone be seen on TCAS? On condition that the pilot reports to ATC, an aircraft's TCAS sees a drone in the vicinity. How can the pilot be sure that it was a drone on TCAS? What kind of symbol is shown on TCAS that can be identified as a drone? Or is it just a primary radar target pick up by TCAS? <Q> No, a drone ...	Normal drones do not have transponders, so they will not be visible on TCAS.
For length in aircraft design, and in weight and balance manuals, what measurement unit does Airbus use? What length measurement unit does Airbus use for aircraft design and in their weight and balance manuals? Meters or centimeters? Possibly they use both like Boeing does for, say, feet plus inches for overall length...	The (few) design drawings I‘ve seen were in millimeters; however I can’t confirm whether that’s the uniform standard.
Why in helicopter autorotation phase the opposing torque is eliminated? As you many know, according to Newton's 3rd law for every action there is an equal and opposite reaction, as the main rotor of a helicopter turns in one direction, the fuselage tends to rotate in opposite direction but when there is no engine power...	In autorotation, the engine and gearbox are not applying any turning force, or torque to the rotor system, so therefore there is no torque reaction in the opposite direction.
What is the definining line between a helicopter and a drone a person can ride in? When I say drone in this context I don't mean an unmanned aircraft. I'm not sure what the terminology of a drone that has been adapted to carry a person? Is this picture below considered a helicopter or what? What if it ran on petroleum?...	The vehicle in your picture is an unmanned aircraft, a drone, a helicopter, a quadcoptor, and a VTOL vehicle all at once.
An appropriate way to practice ATC communications I'm a PPL trainee and I'm looking for a way to improve my radio communication. https://www.liveatc.net/ is a great way to practice but I can't fully understand the conversation between the unit and the aerodrome. If it just had subtitles or general documentation abo...	Live ATC is an excellent way to listen and get familiar with your local airports procedures.
Why was the Spitfire's elliptical wing almost uncopied by other aircraft of World War 2? The Spitfire was one of the most successful designs of its day, with flying qualities of a similar standard to the other best designs of the era. In its decade of production from 1936 it grew bigger , stronger and faster . Y...	Elliptical wings are too expensive to manufacture.
Is it cheaper to drop cargo than to land it? Is it more fuel efficient to drop cargo onto a runway from the air en route to a final destination than to land and unload it using a more fuel efficient plane? <Q> That scenario only makes sense if your airplane stays at cruising altitude: although taxi and takeoff does use...	The only use case for commercial cargo drops seems to be if you need to deliver cargo at a number of closely spaced airports (in which case the short hops would be fuel-inefficient). You have to use an aircraft suited for airborne dropping (i.e. with a tail ramp).
Is it required to be an ATP and work for an airline to be a Captain? I'm just curious if the ATP certificate and working for an airline are prerequisites to being a Captain, or could you have such a title as a PPL or a CPL? <Q> The key phrase, legally speaking, is "pilot in command". <S> On a multi-crew aircraft the ...	The type of pilot license required for each varies by country, type/size of aircraft, and whether the flight is scheduled, charter or private.
How can I best prepare for my first lesson on stalls? I am a flight student preparing to practice stalls and stall recovery in a Tecnam P-2002. I have already done spin recovery. On top of that, what preparation techniques have others found useful? <Q> Just do some reading on stalls and really get to know the 2002's Op...	You will impress your instructor most by being eager to learn and learning quickly, and by having done book work beforehand. That being said, just read up, and really learn the manual.
What type of aircraft would fly with an orange light at night? I know planes usually fly with red lights which seem small in the sky, but last night i saw a bright orange blinking light traveling through the sky; it was bigger then a star but was orange. I thought it might be a helicopter, although I read it could have...	Others have mentioned red anti-collision beacons that might look orange in certain environmental conditions, but there's only one kind of aircraft that shows an intermittent orange light: balloons.
How useful are the AOA Indexers and indicators for jet pilots and civillians? I dont see them neccessary unless you are landing on a aircraft carrier. I just don't know a lot about them. I understand what they do but they just dont seem neccessary unless you are landing a jet to an aircraft carrier where every bit of ...	On the planes I'm more familiar with, we rarely use it at all because it's a real pain to calibrate.
May the Class-E-to-surface airspace near Eagle County Regional airport (KEGE) and Marshall AAF (KFRI) be ignored when the tower is open? May the Class-E-to-surface designation indicated by the dashed magenta lines outside the dashed blue circle at Eagle County Regional airport (KEGE) be ignored when the tower is open...	Whether there has been a mistake in the airspace designations or not, it makes no sense for the airspace within the dashed magenta extensions at these airports not to be treated as Class-E-to-surface airspace when the control tower is open.
Why are thrust reversers not used to slow down to taxi speeds? In reading this question ( Would more throttle when using reverse thrust reduce stopping distance? ), it prompted me to remember that on many of my flights (typically on 737s or CRJ type aircraft), it seems that thrust reversers are used for a few seconds a...	You can use idle reverse, which gives a little bit of braking, while taxiing if the alternative is riding the brakes and overheating them, say like a taxi along a downhill slope or along a slick icy surface where braking is marginal, and you don't want to taxi single engine, and in a pinch you may use reversers to try ...
How do carbureted and fuel injected engines compare in high altitude? I couldn't find enough information on the internet for this topic. What I found can be paraphrased as: Carburetor means easy engine start while fuel injected means manual fuel start up and carburetors are cheaper. So how do carbureted planes comp...	Carbureted engines make use of a carburetor to mix fuel and intake air prior to administrating the airflow to the engine intake manifold.
How useful is skyscrapers and high buildings lighting to get a visual reference for pilots by night? (not obstruction lights, just general lights) I would like to know how useful is skyscrapers and high buildings lighting to get a visual reference for helicopter and small planes pilots by night in cities like New York....	Buildings and their lights can be very useful to aircraft in VFR conditions at night to orient themselves regardless of the type of aircraft.
Why does the headset man not get on the tractor? As far as I can see, the pushback operation of a passenger aircraft is carried out by a similar application at many airports. It's a towbarless tractor and driver who pushes the aircraft together with a headset man connected to the aircraft walking next to the tractor. ...	He needs be able to see everything going on around the aircraft to avoid collisions with other aircraft or stationary objects.
Limitations of bird flight as an aircraft design What is it that stops man from duplicating Bird Flight as Engineering? After all, birds do not require separate propullsion! They use the same wings for propulsion and navigation. My question could be broad. Is it far-fetched ? With solar energy harnessed and electr...	Much of the early history of attempted flight is about failure inspired by bird flight.
Is the seat-belt sign activation when a pilot goes to the lavatory standard procedure? Yesterday, I took an inter-European commercial flight with a popular budget airline. Before take-off, the captain announced that the First Officer would be taking the entire flight today. During the middle of the approximately 2 hou...	In some airlines, this has been standard practice for years, because of fear of accidents suspected to be solo pilots making a horrible mistake .
Are there any current projects/plans for a VTOL passenger airliner? I was very surprised to see there's a seemingly underway project for a VTOL "business aircraft" that seats a few people. http://xtiaircraft.com , https://www.startengine.com/xti-aircraft They assert they've done a 65% scale test. I realize histo...	The amount of traffic is either too low for service by airliners or too high for not building a proper runway that makes VTOL unnecessary waste to make sense.
How can air launched UAV's be decelerated? I am working on disaster relief drones for a college project. I was thinking about having multiple set of drones launched from an aerial vehicle over the disaster prone area. That's when I came across a big challenge. How would you effectively decelerate a UAV that is air lau...	One way might be to design the UAV to be deployed with flight control surfaces folded, use a parachute to decelerate, unfold the flight control surfaces at a safe speed and release the parachute.
Planes returned to base after dumping fuel due toilet issues A colleague of mine experienced this and I was astonished. Flying KLM from PVG to AMS a couple of hours into take off toilets became full. The pilot dumped fuel and returned to PVG. All passengers were re-booked next day. Funnily, she had the same issue fly f...	An aircraft with full lavatory waste tanks can not continue on it's flight as it is a requirement to have a specified number of serviceable toilets on every flight.
What is the backup for a glass cockpit, if a plane loses power to the displays/controls? I'm assuming there is still power to the rest of the plane - maybe it's an unrealistic scenario. <Q> I'll answer this question as "If the glass cockpit instrument fail, what are the backup? <S> " <S> This answer will also be Genera...	It is required by law to have backup of essential instruments. Air Data Computer: gives information regarding airspeed / vertical speed / altitude, thanks to static / dynamic pressure informations.
How could the B-29 bomber back up under its own power? I was watching some footage of the Enola gay I was interested in the part where the plane was backing up over the bomb (starts around 18:27). It appears to be doing this under its own power with the propellers running. Could the B-29 reverse some propellers to...	All the B-29s used for the Atomic bomb missions had reversible pitch propellers.
What is an "all-weather" aircraft? I've read a few times that such-and-such a plane is an "all-weather" aircraft, for example : The McDonnell Douglas F/A-18 Hornet is a twin-engine, supersonic, all-weather, carrier-capable, multirole combat jet. This is quite intriguing and a rather odd thing to specify. A fight...	In the context of a fighter this can mean not only that the aircraft can operate safely in (almost) all weather conditions, but that it can be effective in combat in weather also.
What does the future of the weather radars look like? Planes had weather radars for a long time (Dassault Falcon and Learjet35A) which was useful since you either had to ask ATC, listen the ATIS frequency or ask the flight advisory before flight planning in order to learn the weather. But we are living at a time of tw...	I'd say that what you WILL see though (or are seeing already) is a seamless integration of airborne and ground weather radar via various data channels, as well as electrical storm activity, into aircraft displays, to provide the accurate possible presentation.
Is it possible for a person to fly with mechanical wings attached to his torso? I’ve seen several adaptations of this concept in fiction from the tales of Icarus to Falcon in the MCU. But is it possible in reality for an average human to be able to fly through the air by wearing these gadgets? If it is possible, then...	According to Usherwood, for a human to take flight on flapping wings, “your body would have to be made almost entirely of muscle.”
Does Nitrogen inside commercial airliner wheels prevent blowouts on touchdown? I just watched the first episode of Inside Mighty Machine where civil engineer-turned-host, Chad Zdenek, discussed innovations of the 747. One innovation he discussed was the increased number of wheels and trucks, along with this tidbit: ...	Also, having oxygen in the tyres will oxidize the rubber to some extent, weakening it.
What is the largest (size) solid object ever dropped from an airplane to impact the ground in freefall? What is the record for the largest single solid item that has ever been dropped from an airplane at free fall to the ground? Here, "free fall" means falling vertically, or nearly vertically falling allowing some l...	I can't think of anything dropped from an aircraft larger than the US Space Shuttle when it was dropped from a specially modified 747 during the testing phases of development.
What are some of the longest flights without modern navigation systems? Context: As a private pilot, I enjoy preparing my flights with a mix of paper charts and iPad apps. In flight, my navigation is now often very assisted by the G1000 or iPad, relegating the paper maps to backup. But I remember that, when I was only ...	This list of flight endurance record on Wikipedia lists as number 3 an endurance record of 84 hours 32 minutes between May 25th and 28th 1931. The Rutan Voyager had state-of-the-art navigation on board, including an Omega Navigation System and a GPS receiver.
Can a helicopter mask itself from radar? I have read somewhere that if a helicopter is traveling under 100 km/h and below 5 meters AGL then most radars will ignore it. From what I understand of this process, the radars can pick up things like cars and vehicles driving on the ground and thus need to ignore certain signa...	And yes, many radar installations can be set up to ignore things that don't have at least a certain speed and/or are below a certain altitude.
What could be the cause of an uncommanded roll at high speed? I have a problem with a T-38. There is uncommanded roll to the left when the aircraft flies at 250 knots. But as the aircraft speed goes up around 500 knots, the uncommanded roll is now to the right. During 500 knots we could control the plane with 15-20 ail...	If this were a model aircraft with a wide speed range (like, say, a hand launch glider), I'd expect this to be a cross-trim problem.
How can I fix the stalling of an RC plane after the addition of floats? I'm modifying a RC plane into a bi-plane with floats and it keeps stalling. I don't have a bigger battery or better motor to add so how do I fix this? This is the biggest challenge I've ever faced. <Q> Your model is based on the FX-803 Piper Cub mo...	You could try adding a fixed elevator to provide significant down force at the tail, but this will further compound the drag issue, and could also affect centre of gravity.
What happens if you do emergency landing on a US base in middle of the ocean? A theoretical situation. I fly from Honolulu International to the Bejing but my private jet gets fuel starvation and then I land on the Wake Island airstrip. What happens next? Would the military give me fuel or they would give me shelter a...	In an emergency situation (and declared over the radio) most military facilities will be helpful. If it’s a base there may be no way to actually sell you the fuel as the military is not really a retailer.
Why don't B747s start takeoffs with full throttle? Why does the 747 start takeoff with partial power and increase to full throttle later down the runway, when the A380 for example starts on full? Source This is not the same question as: Is it possible that derated thrust takeoffs are safer than normal takeoffs? W...	You don't want to push the engine to the limit of the operating envelope and then have a gust of cross-wind that causes a compressor surge by disrupting the inlet air flow, until you have enough forward speed to prevent that sort of event from happening.
Is it possible to design a GA plane with a 5' -10' wing span? We see sparrows with 6" wing span land on a dime, yet it seems there no GA planes you can buy or build from a kit with short bodies, short wing spans, something with a 20' landing/takeoff roll, something with folding wings you can drive out of your garage, t...	The simple answer is that everything comes with a trade off, there are plenty of planes with small wing spans like this one , and
How does this RC helicopter keep itself upright? I have this (cheap, beginner-level) RC helicopter: It has 3 controls: one for climbing and descending (collective throttle), one for yawing (differential throttle), and one for pitching (the tail rotor control). There's no roll control. This helicopter seems to have a...	The top rotor is a hinge offset rotor with a very serious stabiliser bar.
Could a helicopter fly like a plane this way? Could a wing be added to a helicopter to allow the entire craft to tip 90 degrees forward allowing it to fly faster like a plane using a fixed wing and leaning into the wing for lift? I understand that there would be major modifications to be made but would there be any be...	A major benefit over the tiltrotor or tiltwing is that you don't need the bearings that can support the thrust of the engines or lift of the wings.
Why don’t airliners have temporary liveries? For buses, it’s quite common to have plastic foil with advertisements on them, but I’ve never seen that on an aircraft. Looking at how aggressively some airlines try to save money, they probably already came up with the idea to sell the space on the side of their aircraft fo...	The airline tries to make it as appealing as possible, because in addition to advertising something, they are also drawing attention to their own brand. Part of the reason is cost. Ryanair is famous for eking out every bit of revenue that they can come up with, and advertise throughout the cabin. It is also common to h...
What's the name of this light airplane? The propeller of this light airplane almost looks like a triangle, so I'm interested in knowing its performance but I need help in identifying this plane because I don't even know her name. <Q> Looks like the "Homebuilt Hornet, one-off wonder plane" on the cover of the March edit...	The aircraft is a Hornet, built as a one-off by Australian Colin Jamieson.
Is it possible to fly backward if you have really strong headwind? Is it possible to fly a plane backwards if you have a really really strong headwind? I mean when you are aloft, you have positive airspeed and airflow over the wings but you have negative ground speed. <Q> Yes, certainly! <S> Example videos: from grou...	If your airspeed is lower than the speed of the headwind, the aircraft will fly backwards relative to the ground. Yes it is possible and here is some evidence Flying Backwards
Do ailerons on opposite wings move together? It seems nicely symmetrical that opposite ailerons would be locked togther, so that when the left wing's ailerons move up, those on the right wing would move down, by the same amount and at the same speed. Is this in fact generally the case on aeroplanes? Or can they be mov...	The basic principle of ailerons is that the aileron on the down-going wing will deflect up, and the aileron on the up-going wing will deflect down.
Could a person damage a jet airliner - from the outside - with their bare hands? Given just a small hammer, I'm pretty sure I could disable a large airliner with a few well-placed blows. What about with my bare hands? In other words, are there any parts of a large aeroplane that are: exposed delicate enough that t...	Putting foreign objects under or between the rotors of brake pads Opening the gear doors of some airlines exposes the air-packs, generators, converters and aux turbine with it's associated mechanisms. Any number of wire bundles & hydraulic lines in the wheel well could probably be damaged with enough determined yanking...
How can pilots sleep or rest merely 1 hour after takeoff? I screenshot this YouTube video . Because the A380 just attained FL250, the flight obviously commenced less than an hour ago. At 14:28 the relief captain ( Robert Juelicher ) leaves the cockpit. At 14:37, ATC clears the flight to climb to FL320. Doubtless, r...	I knew a captain many years ago who would fall asleep right after takeoff.
Are ham radio contacts allowed from inside an airplane? This question probably lies in the middle ground between Amateur Radio.SE and Aviation.SE . I have seen a couple of videos where ham radio contacts are made with people on board a commercial aircraft while in flight. In one of the videos , contact is establis...	If the captain says all such devices must be in flight mode at any particular moment during the flight, you are not allowed to use it and could be arrested if you do.
How strong someone should be in order to fly without "power steering"? Planes these days use fly by wire systems while older ones had a mix of hydraulics with electronic assistance like the MD-11 (And maybe 737-800?). But what would happen if you lost the electronic systems and you had to fly manually? I remember an i...	If you lose all of the hydraulic actuators, you lose the control surface. Like mentioned, in large aircraft with no measures to lighten hinge moments, the flight crew cannot practically control the flight path using manual force.
Why are Vertical tails generally tapered? I'm just intrigued to know why the vertical tail of a majority of aircraft is tapered? Is it due to aerodynamics, structural design or due to some instrumentation or multiple other reasons? <Q> The vertical tail and the horizontal tail are wings, and follow the same constructio...	The wing can be built lighter, root area is larger, torsion stiffness is higher.
Is this one of the engines from the 9/11 aircraft? I ran across an interesting set of post-9/11 photos and I noticed this picture in particular: The closest item on the truck looks a bit like an airplane engine, but I can't tell for sure. Is it one of the engines from the 9/11 aircraft? <Q> They are definitely not ...	Those are Elevator shaft motors , they're wound for high starting torque, not like most pump motors.
On a axial flow turbo fan or turbo jet engine what comes first the rotor or the stator? I've been let to understand that one stage consists of a row of rotors and stators. But I'm not sure which comes first? Does the front fan blades make the first part of the stage (rotor) with a stator section behind? And so on.. Or ...	The simple aerodynamic principle requires a compressor stage to have first a rotor followed by a stator.
Why cruise at 7000' in an A319? I was on a flight from Philadelphia (KPHL) to Boston (KBOS), after some delay and some change of route due to weather, the captain announced that we will be cruising at 7000' due to delays in the area. The history of the flight is here: https://flightaware.com/live/flight/AAL2606/histo...	It was because they could get there faster on a " TEC route ."
Why were the first airplanes "backwards"? In the question Is the location of an aircraft spoiler really that vital? the accepted answer states "Surfaces behind the CoG act as stabilisers, keeping the nose pointing forward. An aeroplane has vertical and horizontal tail surfaces at the back just for this purpose." ...	But there is also a static performance advantage when the elevator is placed forward. Lifting wings have a natural tendency to flip tail over nose because of the way the pressure is distributed.
Is it legal to bring your own survival gear aboard an airliner? Is it legal to bring your own survival gear aboard an airliner? Considering the sobering article by William Langewiesche that is appearing in the July 2019 edition of "The Atlantic", one might want to consider bringing: Oxygen canister with regulator ...	In the US you can carry approved portable oxygen concentrators on board, which would probably be of no use in a depressurization scenario. Yes, it's legal to bring a parachute, if you can fit it within the permitted carry-on limits.
Are gliders susceptible to bird strikes? Gliders don't travel at the high speeds that make bird strikes so devastating in airliners. However, they are also smaller, lighter and softer, and can still move pretty swiftly. Are they also vulnerable to bird strikes? What happens when a large bird collides with a glider? <Q...	Gliders, as every other aircraft, are susceptible to bird strikes.
Does propwash increase pitch stability? Here is a polar for a piston single-engine aircraft: (This is lifted from a Russian manual for Yak-52 , so $C_x$ is drag, $C_D$ , and $C_y$ is lift, $C_L$ ). 1 is the 'normal' case without propwash. 2 is nominal, and 3 is the max takeoff power. It is evident that the w...	The local increase in flow from prop wash increases the tail lift slope. In order to measure pitch stability in flight just measure the stick travel needed to trim different airspeeds for the fixed-stick stability or the stick force needed to trim different airspeeds (without changing the trim setting, of course!)
How does the A350 variable camber system decrease drag? Just curious how the A350 reduces drag/fuel burn by extending the flaps ever so slightly during cruise. Everything I've read about extending flaps says that extending them pushes the centre of pressure rearwards. This causes a pitching down moment, which means you...	What they actually do, in simple terms, is to optimize for induced drag and possibly control, i.e. stability and flight controls by changing the chord distribution.
How to estimate the altitude of an aircraft at a given distance from a runway? What altitude should a heavy class commercial freighter be at on a descent path 17 nautical miles from a runway? (Say SDF airport) <Q> Straight in, on glidepath, about 6000' above the runway. <S> Straight-in & fast, below glidepath at 3000 t...	Instead of estimating, one can use a flight track website such as FlightRadar 24 to get the exact height of the aircraft.
What's the difference between an airplane that stalls nose down or just mushes in a stall? What's the difference between an airplane that stalls nose down or just mushes in a stall? I understand most GA planes go nose down after a stall, but some GA planesdon't drop their nose at all, they mush (they just drop in alti...	If the wing is not producing enough lift to support the weight of the plane but producing enough lift to keep the nose in the air then you have a mushing stall situation. You are absolutely right that it has to do with the pitching moment (Cm) characteristics of the aircraft.
Why do most airliners have underwing engines, while business jets have rear-mounted engines? Why have modern airliners converged on a configuration with two or occasionally four underwing engines, while modern business jets have converged on a configuration with two or occasionally three rear-mounted engines? I am of ...	Engines mounted in pods underneath the wing reduce the upward bending moment of lift creation, and therefore allows for lighter construction. Airliners are designed for loading from elevated passageways at airport terminals.
Why are overwing engines so rare? This comment to a question about underwing vs rear-mounted engines notes the existence of a rarely used third option: overwing engines . There seems to be very few planes using those. What are the disadvantages that makes it so unpopular, and what are the advantages that made it wor...	The reason why engines are mounted under the wing is easy maintenance access and easy visual inspection.
Why do airports remove/realign runways? When looking at Google Earth, I often find myself looking for airports. I often notice that no matter what size airport, over time many of them have abandoned old runways and built new runways in different directions. It doesn't matter between rural and urban, so residential do...	In some cases it also becomes expensive to maintain a runway that may not see much use and it will be shut down.
When do flights get cancelled due to fog? When flights get cancelled due to fog, what triggers the cancellation? Fog is too thick, too wide-spread, blocks the view of tall buildings or other landmarks? Or is the problem the type of air traffic? Too many helicopters or small-ish aircraft? <Q> Other answers have addresse...	So if the departure is cancelled due to fog, it's probably because the RVR is too low (too foggy along the runway itself) for whatever procedure the crew is qualified for.
Why is a reduction in lift called 'drag'? Induced drag is high pressure air 'leaking' to the upper part of the wing (low pressure zone) creating a vortex which means the area of the wing tip with the vortex can't create lift. Drag on the other hand is the opposition to the flow of air. Why is induced drag called a drag...	Induced drag is the drag caused by producing lift.
Can a gas turbine be able to switch from torque to thrust? Can a turbine engine be switched from providing torque (like a helicopter) to the rotor to transfer power to provide exhaust thrust (like a jet plane)? Related: BV-347 upgrade this way? <Q> For example, the GE CF6 , which powers aircraft such as the 747, 767...	The main way to convert a gas turbine to provide thrust rather than shaft horsepower is to attach a large fan or propeller in place of the previous load.
What is the best option when the headwind exceeds the maximum airspeed? In a previous question, Mongo described flying his Cessna with a negative ground speed in a head wind. In this situation, what is the correct thing for a pilot to do, if there is nowhere to land downwind and upwind ground speed is negative? Oth...	If a pilot does find himself in such a situation, changing altitude by a few thousand feet, higher or lower, can very likely change both the wind direction and speed to something that is manageable.
Do helicopters need a class B entry clearance when air / hover taxiing? You're a helicopter pilot at a class B airport. You'd like to taxi to another parking spot. The ground controller could either give you a hover taxi clearance or an air taxi clearance, depending on the situation. Either way will get you off the gro...	Hover taxiing with a helicopter follows the same regulations as taxiing with an aircraft (or helicopter) on wheels.
Why are the flaperons on the 787 located so far in-board? Why are the flaperons positioned in between the outboard and inboard flaps (see 2nd picture)? Why not have them located as far outboard as possible to achieve maximum roll authority? I would think the order would be more efficient if the main flaps were both inb...	I think part of the reason for the placement of the 777 flaperon is that it moves the Fowler flaps away from the jet wash. I can't speak for the designers on the true rationale, but one of the considerations would be a balance between control reversal speeds and roll rate requirements at high speed.
Why aren't aircraft cabins pressurized to sea level pressure? From an article on WHO's website: Although aircraft cabins are pressurized, cabin air pressure at cruising altitude is lower than air pressure at sea level. At typical cruising altitudes in the range 11 000–12 200 m (36 000–40 000 feet), air pressure in ...	Because the extra air would add extra weight!
Does temperature affect dynamic pressure? Taking off on a cold day (5°C), it can take 10 seconds to reach rotation speed but on a hot day (40°C) degrees it will take longer to reach the same speed. Is this due to the dynamic pressure? How does temperature affect it? <Q> Dynamic pressure <S> q <S> $ = <S> ½ <S> \cdot...	Yes, temperature affects dynamic pressure by affecting air density: it reduces with increasing temperature.
Should I have one hand on the throttle during engine ignition? I'm training in a Cessna 172 for my private pilot license (PPL). My flight instructor recommended that I keep my checklist in one hand (so that I can keep looking outside with my peripheral vision) and turn the magneto key with the other. The other da...	Personally, my hand stays on the throttle during all parts of a flight that don't involve cruising.
What would be the impact of replacing the engines on the 737 MAX, not just reworking MCAS? There has obviously been a lot of focus on the MCAS failure following from the 737 MAX crashes. However, the MCAS appears to be a compensating control for design decisions, specifically the replacement of the CFM56-7BE engines on...	To re-engine the plane, you would basically have to re-do a large amount of the FAR 25 certification.
Consequences of stalling while sideslipping in a glider? In a glider, sometimes it's useful to do a side slip with crossed controls. However, when that happens, the pitot tube angle is out of line and the ASI goes to zero, therefore losing any indication of the current airspeed until the sideslip is interrupted. Duri...	Yes if you were to stall the airplane while in a side slip it will probably depart, or start to depart, into a spin.
Why is the UH-60 tail rotor canted? The Sikorsky UH-60 (S-70) has a tail rotor that is canted 20 degrees upwards. Why is that? Picture source <Q> John K and Koyovis 's answers are both correct. <S> However, as a former pilot of the UH-60 and a mechanical engineer here is a simpler version. <S> A helicopter must b...	You could say that it turns the machine into a sort-of quasi tandem rotor helicopter, with just a little bit of tandem-ness.
How did pilots avoid thunderstorms and related weather before “reliable” airborne weather radar was introduced on airliners? How did airline and or mail pilots avoid hazardous weather especially at night before airborne weather radar systems were in use? <Q> They looked out the window! <S> If you are talking about a...	To summarize some of the main points: Reports of winds aloft were reports of the local conditions relayed by radio from aircrews flying in the area of operations and served to inform following pilots.
What is the purpose of the fuel shutoff valve? Most GA planes have a fuel shutoff valve which I don't quite understand the purpose of. Does it cut the fuel flow with the mixture.My theory is to prevent fuel flow at earlier stage for safety reasons? <Q> It's both a maintenance and safety feature. <S> You need a way to...	Either way, fuel is cutoff after the header tank to limit the amount of fuel available in case of an engine fire that could result from a crash.
Are glider winch launches rarer in the USA than in the rest of the world? Why? I had heard before that winch-launching gliders was a relatively rare practice in the USA, while quite common in the rest of the world. My data is mostly anecdotal, but I do know gliding clubs in Europe that exclusively use winches. A rec...	At least in part because airplane fuel, as well as some other costs associated with powered aviation, are cheaper in the US than in many other countries.
What is the lowest-speed bogey a jet fighter can intercept/escort? Jet fighters are made to cruise at a high subsonic speed, even at a supersonic speed (supercruise?). It means that they can be flown comfortably at relatively high speeds. Jet fighters are often used to intercept aircraft, whatever the reason (assistan...	Some fighters are quite controllable at high AoA at speeds lower than optimal for approach, but it is unlikely that a fighter pilot would be comfortable flying formation at such a slow speed. Depending on aircraft type and weight, flaps down approach speeds for most military fighters is in the range of 120 to 150 KIAS....
Why does RPM for a fixed-pitch propeller change with an aircraft's pitch? Talking bout a C-152 - If I pitch the aircraft down, and without adjusting the throttle, the RPM would show an increase. Pitch up, and without adjusting the throttle, the RPM shows a decrease. I've been told that by pitching down you increase ...	Because airspeed influences the effective angle of attack of your propeller blades.
While waiting for a delayed outbound flight how can I guess where's the inbound plane? This summer in Mykonos our flight back to FCO was delayed and nobody at the airport could communicate reliable estimates on when it would be. In that case I managed to find the FCO-JMK inbound flight on FR24 and saw it left FCO with...	Some airports do publish the registration of flights, enabling you to find the right aircraft using a bit of investigative skills.
Why did this aircraft do a ‘spiral’ before landing? There was this WizzAir flight two days ago, from BUD to PMI, and right before landing it did a ‘spiral’ like maneuver. I’ve attached a screenshot. Why did it do that? It looks strange. <Q> The flight was on the 28th, and before orbiting it was around 12:00 UTC. <S> B...	Another reason for the 'spin' is to give time for the aircraft in front to either take-off (departure) or get off (landing) the runway.
Why don't short runways use (downhill) ramps for takeoff? This is a followup on question: Why don't short runways use ramps for takeoff? There are multiple answers to that question that answer why an uphill ramp at the end of the runway does not make sense. But what about going the other way? I would imagine a down...	Any ramp means a height difference between the ramp itself and the runway, for it to actually make a big difference I suspect a fairly long slope from the ramp to the runway is needed, and this will obstruct the runway for landing aircraft.
How and why does the ATR-72 sometimes use reverse thrust to push back from its parking position? Travelling with Czech Airlines via Prague in an ATR-72 I have already experienced multiple times that instead of pushback service the planes simply used their reverse thrust to leave their parking position, even doing a 90°...	As other answers note, for most aircraft, the risk of the engines ingesting FOD while powering back is too high.
What is the most 'environmentally friendly' way to learn to fly? As this question indicates, I've been thinking recently about the environmental impact of flying (since when automated cars are the only means of ground transport, aviation will be responsible for most greenhouse emissions). So, as an amateur, novice p...	Running the simulator is definitely more environment friendly than running even a small aircraft. By using as much simulator time as possible.
What is it exactly about flying a Flyboard across the English channel that made Zapata's thighs burn? CNN's French inventor makes 'beautiful' flight across Channel on hoverboard reports that: "French inventor Franky Zapata has successfully crossed the Channel on a jet-powered hoverboard for the first time, after a ...	Do a mile long run at high speeds and you really feel it in the thighs.
Why do private jets such as Gulfstream fly higher than other civilian jets? I heard in a TV show that private jets such as Gulfstream can fly at about 50,000 ft, higher than other civil jets. Is it an aerodynamic reason (lighter aircraft to be sustained in a less dense air) or does it depend on the fact that a smaller...	Private jets have better power to weight ratio than commercial jets so it is easier to ascend to greater heights.
What accidents have had crew accustomization to warnings among their causes? A non-answer on this question claimed that: the idea that maneuvering with the stall warning activated will somehow damage us, causing us to ignore its warning when the chips are down and AOA is up, is just silly which sounds wrong to me...	Just last year the crash of an Air Niugini flight was directly related to pilots ignoring warnings The captain and first officer ignored a total of 17 audible warnings that they were flying too low. A Valan Air Cargo An-26 crashed in Cote de Ivoire on the 14th of October, 2017 , while performing a charter flight.
How much does it cost extra to fly with one additional passenger? How much does it cost to fly an airplane (like a Boeing or Airbus) when there's one extra passenger there, at an average speed of 475–500 knots (880–926 km/h; 547–575 mph)? That is, about 100kg extra, including clothes and luggage. <Q> I am basing the f...	As a rule of thumb (based on fuel consumption data of a major airline), I've been working with 4 to 5% per hour of flight time (for jets).
Does a 4 bladed prop have almost twice the thrust of a 2 bladed prop? Does a 4 bladed prop have almost twice the thrust of a 2 bladed prop? As a general rule, I'm told GA planes generate 4 lbs of thrust per horsepower. (Source: Zenith School of Airplane Design, Flying on your own Wings) So if you use a 4 bladed prop,...	So a specific 4-bladed propeller might very well give more thrust than a 2-bladed propeller on the same engine, depending on how well-matched it is to the engine and the design details of the propeller.
What are the abandoned technologies in aviation industry And technologies has come to end of to their life cycle Especially technologies that developed for aviation. This could be a manufacturing technology or an engine rather than avionics or sensors. <Q> The biggest one that comes to mind for me is Cathode Ray Tube ...	Rockwell Collins (called something else now) has ceased production of CRT displays and users of Proline CRT Primary Flight Displays, Secondary Flight Displays and EICAS systems are in a scramble to replace the CRTs when they wear out. Another one could be navaids like Non Directional Beacons that are starting to go the...
What determines a plane's range? When a planes maximum range is specified, is fuel [capacity] the only constraint or what else is taken into account? Would it always or ever be the case that a greater fuel capacity will increase range? Interesting long-flight story of 64 days in the air, but it doesn't get too techni...	The airplane's published range will be based on distance that can be flown in still air (excluding winds in other words) with full fuel, departing at max gross weight, when flown at some optimized cruise speed or mach#, at a specified flight level, with normal IFR fuel reserves (fuel to go from A to B, fly an approach,...
Under which condition is a forward CG most critical? This question is from CFI written exam. (6824) “Under which condition is a forward CG most critical?” The answer is “Forward CG is most critical during landing. If it is too far forward, the elevators may not have enough power to get the tail down for a proper app...	If the CG is within limits or even 'on' the fwd limit then the airplane should have no problems with elevator effectiveness. When the CG is too far forward, it can't push down hard enough to hold the nose up at the normal landing speed, and has to go faster to do so.
Are any jet engines used in combat aircraft water cooled? Are any jet engines used in combat aircraft water cooled? If they are not, and instead are air cooled, how can the engine ensure consistent cooling? Wouldn't the airflow passing through whatever radiator implementation it has be greatly affected by the airspeed...	The extended range variant uses an alcohol-water injection system for takeoffs at high gross weights in certain environmental conditions in order to provide cooling for max thrust at takeoff.
Does taking a long time to solo mean that I'll take a long time for training in general? I have a fairly high (in my research - 80hrs and counting) flight hours and still no solo, with landings having been a major reason. There is definitely progress - but I am not convinced I'll solo before 100. I am 43 in decent shap...	If you have 80 flight hours logged and no solo, unless there is some unusual extenuating factor (e.g. those 80 hours were spread over many years), something is seriously wrong.

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