Stalling in Landing Configuration...?
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A few of us Private Pilots got into flying via Gliding, and for every winch launch you have ever done you have to be very quick to lower the nose. At the end of the launch, when you are 1400ft agl, the glider has a nose-up attitude of about 25 degrees, The cable back-releases, as it is supposed to do. Then you simultaneously give the cable-release a precautionary two tugs, and lower the nose to below the horizon. It is only when you get to fly powered aircraft, that the application of power is also required.
If you fly anything larger, with tonnes of inertia, then that is a different problem, but after all this is the Private Flying Forum.
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If you fly anything larger, with tonnes of inertia, then that is a different problem, but after all this is the Private Flying Forum.
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Moderator
but after all this is the Private Flying Forum.
It is only when you get to fly powered aircraft, that the application of power is also required.
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There is no difference between dealing with a stall be it a RC aircraft, glider, microlight, SEP,MEP, turboprop or Jet be it BAe 146 or a swept wing 747. (we won't get into super stalls with T tails)
All of the above will unstall without changing the power setting by reducing the AoA.
If a pilot is trained from the outset that Stalling has absolutely nothing to do with airspeed and is only a function of angle of attack then stall recovery is very simple logic.
If they think stalling is to do with airspeed then logically they want to apply power thinking they are going to increase it and stop descending.
I might add the airspeed theory was the first one for RAF pilots in WW1 and the procedure if the plane stalled was to put the power high and pull back on the stick as hard as you could. This was universally fatal. Then someone allowed the nose to drop either by accident or on purpose. They survived and then tried it again and survived. They went and told the powers that be what they had discovered and got Court Marshalled for disobeying flying instructions. By WW2 they had dumped the airspeed nonsense.
All of the above will unstall without changing the power setting by reducing the AoA.
If a pilot is trained from the outset that Stalling has absolutely nothing to do with airspeed and is only a function of angle of attack then stall recovery is very simple logic.
If they think stalling is to do with airspeed then logically they want to apply power thinking they are going to increase it and stop descending.
I might add the airspeed theory was the first one for RAF pilots in WW1 and the procedure if the plane stalled was to put the power high and pull back on the stick as hard as you could. This was universally fatal. Then someone allowed the nose to drop either by accident or on purpose. They survived and then tried it again and survived. They went and told the powers that be what they had discovered and got Court Marshalled for disobeying flying instructions. By WW2 they had dumped the airspeed nonsense.
Interesting statements,
But without an A of A device I actually do watch the ASI like a hawk when slowing down and making turns from downwind to base & finals.
I usually improve my chances at these lower speed over stall margins by having a couple of flap stages too.
So in a real world "stall speed" is a truism.
mike hallam
But without an A of A device I actually do watch the ASI like a hawk when slowing down and making turns from downwind to base & finals.
I usually improve my chances at these lower speed over stall margins by having a couple of flap stages too.
So in a real world "stall speed" is a truism.
mike hallam
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Interesting statements,
But without an A of A device I actually do watch the ASI like a hawk when slowing down and making turns from downwind to base & finals.
I usually improve my chances at these lower speed over stall margins by having a couple of flap stages too.
So in a real world "stall speed" is a truism.
mike hallam
But without an A of A device I actually do watch the ASI like a hawk when slowing down and making turns from downwind to base & finals.
I usually improve my chances at these lower speed over stall margins by having a couple of flap stages too.
So in a real world "stall speed" is a truism.
mike hallam
A stall and a wing drop at that moment will probably end your flying career.
SND
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A few of us Private Pilots got into flying via Gliding, and for every winch launch you have ever done you have to be very quick to lower the nose. At the end of the launch, when you are 1400ft agl, the glider has a nose-up attitude of about 25 degrees, The cable back-releases, as it is supposed to do. Then you simultaneously give the cable-release a precautionary two tugs, and lower the nose to below the horizon. It is only when you get to fly powered aircraft, that the application of power is also required.
If you fly anything larger, with tonnes of inertia, then that is a different problem, but after all this is the Private Flying Forum.
.
If you fly anything larger, with tonnes of inertia, then that is a different problem, but after all this is the Private Flying Forum.
.
Also, as said, engine power is not required to unstall any aircraft.
Unfortunately not many light aircraft have an angle of attack indicator, so the only reference we have is the ASI, or the shoogly stick.
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But without an A of A device
Every aircraft is fitted with an AoA device its called a window. instructors don't look across the cockpit to know your airspeed is off. We just look at the attitude.
There are also a huge number of collisions at that same point a trimmed aircraft will keep the same speed if the pilot doesn't annoy it. So if you attitude is set and your trimmed, the speed is going to be good. If the runway is going up in the screen you put some power on if its going down you take some off, if its staying in the same position you leave it alone.
So look out to me look out carries more priority. While doing the look out you have access to the aircrafts speed via the window and the attitude. Nose high your slow, nose low your fast.
Some of us made our students do circuits without any instruments at all and usually the student was spot on the speeds required and height all done by attitude and sound of the engine definitely more spot on and consistent than the ones that had got used to needle chasing.
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I don't know why I'm bothering to reply to this, but I was always taught, release before the thing back releases because otherwise you have passed the overhead the winch and if there is little or no wind you will drop a 1200ft pile of high tensile spaghetti all over the winch.
- Release at pilots discretion
- Release at the winch drivers discretion: The winch driver will release the tension on the cable. This can be felt in the airplane, so you release the cable
- Release by flying over the winch and let the safety mechanism do its work
Which method is used depends on the local culture. But it also depends on the prevailing wind direction and strength. With a strong headwind the chance that the cable drops on, or behind the winch is virtually nonexistent, so the winch driver can continue the launch until the aircraft releases itself through the safety mechanism - which is almost dead overhead the winch. OTOH with light winds, winds 90 degrees cross to the launch direction, or even with a slight tailwind (yes it happens), the winch driver needs to signal the pilot to release a lot earlier in order to avoid the 1200' spaghetti.
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A few of us Private Pilots got into flying via Gliding, and for every winch launch you have ever done you have to be very quick to lower the nose. At the end of the launch, when you are 1400ft agl, the glider has a nose-up attitude of about 25 degrees, The cable back-releases, as it is supposed to do. Then you simultaneously give the cable-release a precautionary two tugs, and lower the nose to below the horizon. It is only when you get to fly powered aircraft, that the application of power is also required.
If you fly anything larger, with tonnes of inertia, then that is a different problem, but after all this is the Private Flying Forum.
.
If you fly anything larger, with tonnes of inertia, then that is a different problem, but after all this is the Private Flying Forum.
.
At the gliding club where I learned as a teenager they taught that the pilot should release, the gliding club where I get to spend not enough of my time take the same view, they see it as poor airmanship due to the lack of thought for the winch driver.
SND
Unless you are flying with a retrieve cable, as at the Long Mynd. Standard practice is to let the back release pull the cable off, after the main winch driver has cut the power.
There is an interesting paper on this subject at:
Brunel University Research Archive: Evaluating a set of stall recovery actions for single engine light aeroplanes
(The full docx report is downloadable from near the foot of the page referenced above.)
One type of aircraft did not recover from a stall using elevator alone - power was necessary.
The CAA technique is in "HANDLING SENSE LEAFLET 2: STALL/SPIN AWARENESS"
https://publicapps.caa.co.uk/docs/33...09webHSL02.pdf
Brunel University Research Archive: Evaluating a set of stall recovery actions for single engine light aeroplanes
(The full docx report is downloadable from near the foot of the page referenced above.)
One type of aircraft did not recover from a stall using elevator alone - power was necessary.
The CAA technique is in "HANDLING SENSE LEAFLET 2: STALL/SPIN AWARENESS"
https://publicapps.caa.co.uk/docs/33...09webHSL02.pdf
This paper considers four alternative sets of actions that a pilot may use to recover an aeroplane from the stall. These actions: Those published by the UK CAA and the US FAA, as well as a power delayed sequence and a pitch delayed sequence, were evaluated on 14 single engine piston aeroplane types. In a limited number of types (five in cruise configuration, two in landing configuration) the pitch delayed recovery gave a safe response and least height loss, but in a greater number of types (six and eight in cruise and landing configurations respectively) it resulted in further post-stall uncommanded motion. The other sets of actions all gave a consistent recovery from the stall, but the least height loss in recovery was also consistently the CAA sequence of simultaneous full power and nose-down pitching input, which normally resulted in approximately two thirds the height loss of the FAA's pitch first then power method, which in turn resulted in about 90% of the height loss of the trialled power delayed recovery. Additionally the CAA recovery gave the least variation in height loss during stall recovery. It was also found that all of the aeroplane types evaluated except for one microlight aeroplane of unusual design, displayed a pitch-up with increased power in the normal (pre-stall) flight regime. Reducing this to separate components it was therefore shown that pitch control is of primary importance and should be used to provide immediate stall recovery. The thrust control can additionally be used as early as possible to minimise height loss, but if the thrust control is used before the pitch control in the stall or post-stall flight regime, there is some risk of subsequent loss of control. Finally, from the discussion on stall recovery methods, questions for Regulatory Authorities are put forward that should address the current practices. © 2014 Royal Aeronautical Society.
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nice study.
table 4 is particularly impressive with the delayed pitch
Yep that's what a tramahawk will do if you try and power out.
That really didn't surprise me but there were a few others that surprised me how much they bite if you do power first.
The BTW the aircraft that doesn't recover without power is a microlight with a high C of G push engine on the back and caniars doing pitch on the front. I will defer to those that know, but I suspect it wouldn't pass certification these days.
table 4 is particularly impressive with the delayed pitch
Severe right wing drop which may have been an incipient spin but recovered from this immediately the stick was moved forward
That really didn't surprise me but there were a few others that surprised me how much they bite if you do power first.
The BTW the aircraft that doesn't recover without power is a microlight with a high C of G push engine on the back and caniars doing pitch on the front. I will defer to those that know, but I suspect it wouldn't pass certification these days.
The Goldwing is pre Sections S, and has a whole bunch of stuff that wouldn't get approved these days. It was approved in the late 80s on the basis of grandfather rights and partial compliance with the airworthiness standard. It was used as part of the opening discussion, and not actually tested for the paper.
G
G
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Was yourself involved?
It was a very well written study and also practical.
If any of the owners are reading that donated hours on aircraft... thank you very much they were not wasted at all.
The controllability post 1st stall is always an issue even in the works machine. When people do them both at the same time its a rare person that can control the pitch to just enough and not give it huge pitch changes. When they do the roller coaster starts. Thankfully at work they have standardised on the pitch pause power recovery. Just like I concluded worked the best teaching ppl years ago.
BTW I was taught the power out on my ppl but even at that stage it was pretty obvious it was nonsense and asking for trouble. I will admit I have some 900 hours teaching on PA38's which tends to focus an instructors mind on avoiding anything that's likely to throw you into a spin. And its stood me in good stead ever since. A calm 1-2-3 recovery looses less height and everything is back under control quicker than shoving both hands forward and then trying to sort the resulting dynamic situation out.
To note for the twin drivers. I have also be made to do single engine stalls in the sim to try and show that its a bad technique to slowly apply full power keeping the wings level and yaw under control. Yes I did loose loads of height.... but at least I didn't have a Vmca rollover like my colleague did doing it the way the TRE wanted it. I lost 600ft over 4 seconds he lost 3000ft in about 2 seconds and then we had to have a break because the sim went into a sulk.
It was a very well written study and also practical.
If any of the owners are reading that donated hours on aircraft... thank you very much they were not wasted at all.
The controllability post 1st stall is always an issue even in the works machine. When people do them both at the same time its a rare person that can control the pitch to just enough and not give it huge pitch changes. When they do the roller coaster starts. Thankfully at work they have standardised on the pitch pause power recovery. Just like I concluded worked the best teaching ppl years ago.
BTW I was taught the power out on my ppl but even at that stage it was pretty obvious it was nonsense and asking for trouble. I will admit I have some 900 hours teaching on PA38's which tends to focus an instructors mind on avoiding anything that's likely to throw you into a spin. And its stood me in good stead ever since. A calm 1-2-3 recovery looses less height and everything is back under control quicker than shoving both hands forward and then trying to sort the resulting dynamic situation out.
To note for the twin drivers. I have also be made to do single engine stalls in the sim to try and show that its a bad technique to slowly apply full power keeping the wings level and yaw under control. Yes I did loose loads of height.... but at least I didn't have a Vmca rollover like my colleague did doing it the way the TRE wanted it. I lost 600ft over 4 seconds he lost 3000ft in about 2 seconds and then we had to have a break because the sim went into a sulk.
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An RAeS award to the people who did the work, not for amazing fakery flying a vintage biplane to nice places. It’ll never catch on 😜😜
SND
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Twas a long time ago though, K13s in those days.
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That was what I was taught, drop the nose and release.
If you hung on too long the winch driver cut the power and the back release went, considered bad practice.
Also K13 days, when the pilot was trusted to control his own launch perhaps?
If you hung on too long the winch driver cut the power and the back release went, considered bad practice.
Also K13 days, when the pilot was trusted to control his own launch perhaps?
Yes, that's the case with only one cable, but the cable from the retrieve winch has quite a lot of drag, and as soon as the driver on the main winch cuts the power, the cable back releases, then both winch drivers wind cable in until the two cables (joined near to the cable parachute) land. Then the retrieve winch driver pulls the cable back to the launch point.
It's actually easier for everyone if the main winch driver controls the launch speed and release, and the pilot controls the attitude.
It's not quite the same as with a single cable. In that case the pilot normally releases the cable, after releasing the stick back pressure.
I did spend a season driving a winch with the retrieve system described, so have some slight idea how it works. I'm in current winch launch practice from the glider end, too.
It's actually easier for everyone if the main winch driver controls the launch speed and release, and the pilot controls the attitude.
It's not quite the same as with a single cable. In that case the pilot normally releases the cable, after releasing the stick back pressure.
I did spend a season driving a winch with the retrieve system described, so have some slight idea how it works. I'm in current winch launch practice from the glider end, too.
Thread Starter
I think we all now realise that each airplane may have a 'best recovery method', but back in my model flying days, I had a high wing model with dihedral, that would fly a very stabilised Dutch-Roll. I had to set about 80% power, hold the elevator way back, then it would fall off to the left, followed 2 seconds later by a fall off to the right, and would keep this R/L/R/L/R going for as long as I held the controls set... All without loosing any height, or deviating from a straight course.
The model was called a 'Jumper' and I don't think it was modeled on any full size aircraft.
It would be interesting to know if any 'spam can' needs no alteration of the controls at the first sign of a wing-drop.
Also from Model Gliding, I found out that the in-built pitch stability of the aircraft will get them out of most stall conditions. I would set the up-elevator trim so that the glider would just start to porpoise, without any inputs from me, indicating it was near its stall speed. Then I would add 3 or 4 clicks of down elevator, and the glider was then at the correct speed to go thermal chasing all on its own.
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The model was called a 'Jumper' and I don't think it was modeled on any full size aircraft.
It would be interesting to know if any 'spam can' needs no alteration of the controls at the first sign of a wing-drop.
Also from Model Gliding, I found out that the in-built pitch stability of the aircraft will get them out of most stall conditions. I would set the up-elevator trim so that the glider would just start to porpoise, without any inputs from me, indicating it was near its stall speed. Then I would add 3 or 4 clicks of down elevator, and the glider was then at the correct speed to go thermal chasing all on its own.
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Last edited by scifi; 24th Apr 2018 at 10:45. Reason: time constant