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34

As far as I can tell, NASA has never given a straight-forward answer to this question. The theoretical stall AoA is likely in the 33-40° range (see reason for that guess below). However, at operational airspeeds, the orbiter becomes aerodynamically unstable at a lower angle of attack than the stall angle. Therefore, the stall angle never mattered for shuttle ...


-3

The minimum speed is 110 knots in level flight pattern .http://www.dailysabah.com/turkey/2017/01/25/turkish-aerobats-break-slowest-airspeed-record-in-breathtaking-show


2

It depends on the weight of the F-16. If weight is below afterburner thrust the F-16 can fly vertical, without having to worry about any lift that the wings are generating. At airshows it passes by straight and level with the nose pointing almost straight up. So its stall speed in that situation is Not Defined: even at speed zero there is no stall.


12

The other answers have already correctly stated that lowering the nose is the first action, and that you do not fiddle with the configuration when stalled. I'd like to add a point relating to smaller propeller aircraft: when flying at the edge of stall, or even stalled (some GA planes are surprisingly docile even under full stall), you do not want to ...


6

The priority is to unload the wings: which means lower the G load on the wings because the stall speed increases with higher G loads and reduces with lower G loads until reaching 0 with 0 G. So an aircraft can stall at any speed really, it all depends on the G factor it is subjected to. That's why when you stall the first thing you should do is to lower the ...


1

I interpreted the values as follows: The angle of attack at which the specified propeller airfoil generates zero lift The change in lift coefficient per change in $\alpha$ in radians The same as 2, except that it is this value around the stall angle (it is mostly a safety factor for numerical calculations I think, small but non-zero) Maximum $C_l$, which is ...


29

The instinct drilled into a pilot's head from the beginning as the primary response is "lower the nose" to lower AOA. If you learn in a glider, that's the only option, so it's easy to drill the instinct into peoples' heads (one reason that glider training before power is so good for pilot skills later). In a power plane, it's lower the nose and add as much ...


4

The priority is to reduce the AoA. This can be done in several ways (changing the attitude by lowering the nose, changing the chord line by lowering the flaps, thus reducing the effective AoA, increasing the airspeed by opening the throttle, thus lowering the effective Aoa...) The choice depends on the flight conditions, and it's the pilot's choice...


3

No, it would not have helped by itself. What could prevent a stall or recover the aircraft from an incipient stall would be a counteracting movement of that canard surface, but that would need to be commanded by the pilot. It makes little difference if that control surface is ahead or behind the wing as long as it has enough lift potential left to produce ...


0

NO, the Wright British Patent No. 6732 appears to deal with post stall control of the aircraft. Though 1904 A.D. is a long time ago, a modern wings center of lift still shifts backwards to the center of the wing after it stalls. Even their curiously proto laminar/Davis design thin undercambered wings had a center of lift further forward at lower AOA "...


0

What they had was a further called canard configuration with the horizontal stabilizer ahead of the wing. They stated that the stabilizer is angled negatively and not loaded in normal conditions. The center or pressure is located 1:3 of the wing cord towards the leading edge. For this reason in flight the wing has a tendency to tilt up, pitching the nose of ...


1

They are describing the Flyer's canard configuration. The canard surface is the "horizontal rudder". The wing airfoils they and others were using at the time had very strong pitching moments at stall AOA (due to the constant curvature or arc of the profile as you can see in the sketch), that would overpower the downforce of a horizontal tail, or even cause ...


2

Sounds similar to the De Havilland Comet 1's other problem. On 26 October 1952, the Comet suffered its first hull loss when a BOAC flight departing Rome's Ciampino airport failed to become airborne and ran into rough ground at the end of the runway. ... Both early accidents were originally attributed to pilot error, as over-rotation had led ...


2

There are a couple I can think of off-hand from the last couple of decades (in addition to the ones already listed in other answers): 1. National Airlines Flight 102 I suppose whether this one counts depends on exactly what definition of "airliner" you're using. Certainly, the 747-400 is normally considered an airliner, though this was its cargo variant. I ...


1

The 1972 crash of BEA flight 548 in Staines, near Heathrow Airport, London, was, and remains, the most lethal flying accident (excluding terrorism) in the UK. It was a significant incident with respect to raising issues of crisis management in the cockpit, and in bringing about the use of cockpit voice recorders. The proximate cause was a decrease in the ...


4

Two other catastrophic accidents during takeoff phase occurred on flight testing for transport category aircraft, though both of them are business jets: 1. Bombardier Challenger 604, 2000, Wichita Aggressive takeoff rotation led to fuel migration and shifted the aircraft CG aft of the allowed limits. The combined effect of the large initial rate of ...


3

Several examples on Skybrary One of the most notorious cases is arguably Northwest's MD-82 On 16 August 1987, an MD-82 being operated by Northwest Airlines on a scheduled passenger flight from Detroit MI to Phoenix AZ failed to get properly airborne in day VMC and, after damaging impact with obstacles within the airport perimeter after climbing to ...


13

There are two fairly recent airliner crashes I can think of that were the direct result of an aerodynamic stall, one is Air France 447 and the other is Colgan Air 3407. AF447 was at cruise height when the incident began, so that one does not fit with your question. Colgan3407 was landing, so was pretty much "low level" (Does "jet" permit a turboprop?). ...


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