Stall Warning

[dchuwa]

Hello Guys ?
i just want to understand this !
1 . Is it good to land with stall warning in such a/c like piper 28 or any other training a/c ? just help me guys

[Hakeem]

@ dchuwa

Hi mate,

Actually its good to have stall warning just before touch down as long as you are not flaring too high.

But basically it depends on the pilot, Whether he is flaring at the right height or not......

This what my idea about it.....

[DB6]

Not if it's been going for about 10 seconds, but for it to be just sounding as you touch down would imply that the aircraft is flying about 5 knots faster than the slowest speed at which it can fly in that configuration, which is just about perfect for landing.

[Molesworth 1]

I never do, but not to say it's wrong. As long as there is no damage to the aircraft or to the crew and passengers it's a good landing. Might help the tyres last longer.

[Piper.Classique]

Not if it's been going for about 10 seconds, but for it to be just sounding as you touch down would imply that the aircraft is flying about 5 knots faster than the slowest speed at which it can fly in that configuration, which is just about perfect for landing.

Quite correct, assuming a good calibration of the stall warner. I would expect the stall warner to do its thing in the hold-off. You might want to try some slow flying in your approach configuration to check this. Some can be a few knots out. As ever, talk to your instructor

[Gertrude the Wombat]

I do warn my passengers that if they hear that noise during the last couple of seconds of landing it's perfectly normal.

[Johnm]

In a Pa28 if it's not sounding as you touch down you are probably landing too flat and/or fast and putting unwanted load on the nose wheel.

[Pull what]

The best procedure is to cross the threshold at the correct speed and round out at the correct height. The stall warner is to warn of the approach to a stall not for landing advice.

[Johnm]

The best procedure is to cross the threshold at the correct speed and round out at the correct height. The stall warner is to warn of the approach to a stall not for landing advice.

Very true and if you do that in a PA28 the stall warner will likely chirp just before you touch down

[Pilot DAR]

The stall warner is to warn of the approach to a stall not for landing advice.

I don't entirely agree. Generally, in light aircraft, a well accomplished landing is a result of a well controlled near stall, just above the runway.

Therefore, if you get a stall warning just above the runway, I would say it is additional useful information about the progress of the landing.

Alternatively, for those aircraft types where a near stall condition at toughdown is inadviseable (Lake LA-4 during water landing, and some taildraggers, for example), a stall warning during the landing is probably an indication that immediate intervention is required. Good advice to be getting at that moment!

Either way, the stall warning is providing useful information for a good landing, if correctly interpreted.

[rjay259]

Sorry but why would you want to hear a stall warner just above the runway?
To me it says that you are not flying the aircraft correctly at such a critical stage of flight.
Whats to say a gust of wind will not catch you at that very moment and lift you five or so feet. For the inexperienced that will cause damage to aircraft and/or people.
Fly the aircraft onto the runway at the correct speed (not forgetting the flare obviously).

When there is more experience behind the pilot then maybe but if you are starting out/ half way through, fly it onto the deck (with flare).

The cost of a tyres compared to new wing spars/root and or aircraft are incomparable.

[Piper.Classique]

Sorry but why would you want to hear a stall warner just above the runway?
To me it says that you are not flying the aircraft correctly at such a critical stage of flight.

Well, RJAY quite a lot of aircraft will bounce right back into the air if you fly them on to the ground with excess speed, not to mention flat landings with broken nosewheels, or a glorious balloon due to pulling a bit with excess speed, or yet a wheelbarrow landing. I fly mostly a taildragger (Pa18-150) without a stall warning device, but a fair bit as well in a DR400. Neither of them appreciate being shoved onto the ground at high speed, though the cub will take it better than the robin as long as I keep the tail well up. If you have got a stall warner, it is usually considered rather a good thing to hear it in the hold-off, which is or should be only a few inches above the ground. The idea is after all to land without any lift remaining....otherwise you should still be airborne, yes? We call this a hold-off, or if you are in France, 'un palier de de-acceleration' ie a level slow-down, which I think explains it rather well. And all my students have to be able to do this before doing any flying on their own. BTW, I am currently instructing on three axis microlights, but I have a reasonable amount of instructing on SEP in the past.

[Pilot DAR]

Fly the aircraft onto the runway at the correct speed (not forgetting the flare obviously).

Not the best technique in my experience. I have never seen a "correct speed" published for flying and aircraft onto a runway. My experience with flight manuals has been that phrases like "reduce speed until tochdown" or "touch down a low speed" are the common way of expressing this. A number is not. Added to which, you really don't want the pilot "head in" during the final stage of landing, so watching the ASI is bad. Stall warning systems generally provide appropriate anagle of attack information to pilots, with a suitable margin of safety, and "head in" not necessary.

if you are starting out/ half way through, fly it onto the deck (with flare).

I do not agree. Learn it right, from the beginning, don't practice porr habits, with the intent of changing later. If the "flare" is not an effective pitch change to both arrest the descent, and cause a reduction in speed, it will probably do neither adequately. When an aircraft contacts the ground with a reserve of speed, returning to flight is possible, and likely. If, during this "overspeed" contact with the gorund, the descent rate has not been arrested, returning to flight (bounce) is certain. The second (or subsequent landing attempt (assuming a go around was not executed), will end up being a full stall landing, and will be much less under control than were it to have been planned that way from the start. Unless you are flying an aircraft with very high wing loading, and/or lift defeating devices such as spoilers, it is very hard to contact the ground at much over 1.3Vs, and get a good landing out of it.

The cost of a tyres compared to new wing spars/root and or aircraft are incomparable

Well, yes, though I have never seen damaged wings, or any other structure, resulting from a full stall landing inches over the runway. I have very certainly seen damaged aircraft resulting from being "flown on" to the runway (and generally either bouncing badly, or running off to on side due to wheelbarrowing). I have seen aircraft damaged from being dropped on from high, after stalling with no energy after a bounce. The stall was okay, it was the zero energy, and high (many feet above the runway) altitude which were the problem. I have seen expensive damage of all types to nosewheel asemblies, resulting from three pointers in tricycle aircraft. The most extreme being the guy who ran off the end of the runway, and during the invesigation, the non-pilot witness asking the invesigator: "Don't the main wheels have to be on the ground also, for the brakes to work?".

When a GA aircraft is fully stalled, you have full control with the rudder, and adequate control with the ailerons. Keeping it straight down the runway should be no problem. If you have a negligible descent rate inches above the runway, and are slowing down under control, you're going to have a good landing. Even a gusty day, within reason for the aircraft type, should not make the aircraft beyond controllable for a landing with a peeping stall warning horn. Full on blaring... I agree, not a good thing to attempt. Main reason: likely tail strike, and that is more expensive than rubber!

Deccelerating in the air just over the runway is free, and more effective than using brakes.

Everything within reason, but planning to get the plane on the ground much before you hear the stall warning, has the potential result in a not so good landing. You certainly can get a good landing without hearing the stall warning, but avoiding actuating the stall warning at touchdown is a poor idea. A pilot demonstrating this to me, would not get to fly my plane without some additional training.

Pilot DAR

[ChrisVJ]

When I learned to fly, roughly 47 years ago, it appeared there was just one way to do things. Pretty well all schools and instructors taught the same thing.

Whether it is a failure of passing down the wisdom or that too many people have too much time on their hands or . . . whatever, it seems these days that every Tom, Dick and Harry has a "brand new, all singing, all dancing theory" about a 'new way of doing things." Some of them make no sense at all and some of them are downright dangerous. The old teachings may have been marginally incorrect but the practices that stemmed from them worked, day in day out. Some of the new teachings are just downright stupid, eg, I have seen it written on an aircraft site that it is the vortices that keep an aircraft in the air. Hmmmm.

Personally I am against overbearing regulation and for free speech but one has to wonder if our authorities should insist that only proven theories and practices are taught and lay down just exactly how.