Question For The Experts - Use Of Flaps.
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The last pilot that I saw "reconfiguring" their flaps close to the ground, destroyed their aircraft. It was repaired, but it wasn't cheap. Everything in front of the firewall tore off. They released the flaps in a go-around and belly-flopped into the ground. They exited the aircraft by stepping out where the windscreen was 
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Turnback successful from 400 feet, and had to use full flap! We may have made it from less 
These tests were done at 45 degrees AOB.
As soon as Chuckles edits the video I am sure he will upload it.
Disclaimer: not all aircraft will be capable of doing this.
These tests were done at 45 degrees AOB.As soon as Chuckles edits the video I am sure he will upload it.
Disclaimer: not all aircraft will be capable of doing this.
Last edited by Jabawocky; 1st Feb 2011 at 12:39. Reason: attempt to keep T28D happy....
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A turn back from 400 ft in any aircraft is irresponsible and I hope there are no young people learning who read this that ever attempt such a patently risky foolhardy manouver.
400 ft and silence , land straight ahead and give the aircraft to the insurance company.
NEVER turn back at low level.
400 ft and silence , land straight ahead and give the aircraft to the insurance company.
NEVER turn back at low level.
Grandpa Aerotart
Rather absolutist there T28D - do you include Gliders in the statement 'in any aircraft is irresponsible'?
You'd be aware that glider pilots are required to demonstrate a turn back from <300' (if memory serves) in the event of a broken tow rope before they are allowed to solo?
That being the case it would seem to me that its merely a matter of how good a glider you're flying. The RV10 is an exceptional glider. Mr Vans designed one hell of a wing.
Jaba was curious and so was I. I strongly suspected the RV10 would do it with ease and that was how it panned out. After some practice at a safe altitude to blow off the cobwebs (its been decades since I was taught how on an Instructors Rating course - and not long after did one in anger in a C182) we did a couple on takeoff from 06 at YCAB.
Negligible wind. The first time we 'failed' the engine at 500' and we were so high lining up on 24 it would have required aggressive sideslipping with full flap to not over run the end of the runway.
The second time we 'failed' the engine at 400' and still managed to comfortably get around and land on 24. With a little headwind and 15 degrees of flap I reckon 300' would be quite doable. From 600-700' we could have turned left or right and after a short downwind leg turned a further 180 degrees and landed on 12/30.
We allowed a couple of seconds 'reaction time' on each occasion although I fall into the 'surprised when the engine doesn't fail' category and in any of the real engine failures I have had I certainly didn't sit there dumb founded for several seconds.
When I have had time to edit/format the vid I will post it.
You'd be aware that glider pilots are required to demonstrate a turn back from <300' (if memory serves) in the event of a broken tow rope before they are allowed to solo?
That being the case it would seem to me that its merely a matter of how good a glider you're flying. The RV10 is an exceptional glider. Mr Vans designed one hell of a wing.
Jaba was curious and so was I. I strongly suspected the RV10 would do it with ease and that was how it panned out. After some practice at a safe altitude to blow off the cobwebs (its been decades since I was taught how on an Instructors Rating course - and not long after did one in anger in a C182) we did a couple on takeoff from 06 at YCAB.
Negligible wind. The first time we 'failed' the engine at 500' and we were so high lining up on 24 it would have required aggressive sideslipping with full flap to not over run the end of the runway.
The second time we 'failed' the engine at 400' and still managed to comfortably get around and land on 24. With a little headwind and 15 degrees of flap I reckon 300' would be quite doable. From 600-700' we could have turned left or right and after a short downwind leg turned a further 180 degrees and landed on 12/30.
We allowed a couple of seconds 'reaction time' on each occasion although I fall into the 'surprised when the engine doesn't fail' category and in any of the real engine failures I have had I certainly didn't sit there dumb founded for several seconds.
When I have had time to edit/format the vid I will post it.
Thread Starter
XXX:
I agree, not a good idea. However what I'm talking about was retracting flap on approach at 1.3 Vs. That should provide a slight pitch up and a better glide angle.
Whitts flying has this to say:
http://www.whittsflying.com/web/page...e_of_Flaps.htm
I would add that no one has ever taught or shown me that, and I ain't tryin it on my own.
The last pilot that I saw "reconfiguring" their flaps close to the ground, destroyed their aircraft. It was repaired, but it wasn't cheap. Everything in front of the firewall tore off. They released the flaps in a go-around and belly-flopped into the ground. They exited the aircraft by stepping out where the windscreen was
I agree, not a good idea. However what I'm talking about was retracting flap on approach at 1.3 Vs. That should provide a slight pitch up and a better glide angle.
Whitts flying has this to say:
Flap Emergency (Instructor)
A simulated emergency-landing situation that deserves instructional attention is that of engine-failure on short final. Create the following situation on a 5000' or more runway. Arrive at short final with full flaps, at least 1500 RPM and the slowest approved approach speed. At 400' take off the power. The student should immediately remove all flaps and use the yoke to maintain the same approach speed. The initial reduction of power should make it obvious that the aircraft will be unable to reach the runway in its full flap configuration. The immediate removal of flaps will cause a sink of nearly 200'. These negatives are soon seen to be offset by the flatter glide and extended glide path made possible by the absence of the flaps. When done smoothly, touchdown should occur about 2000' down the runway. Introduce this procedure shortly before solo. In 35 years this knowledge has prevented at least two off-airport landings by my soloing students at Concord CA..
A simulated emergency-landing situation that deserves instructional attention is that of engine-failure on short final. Create the following situation on a 5000' or more runway. Arrive at short final with full flaps, at least 1500 RPM and the slowest approved approach speed. At 400' take off the power. The student should immediately remove all flaps and use the yoke to maintain the same approach speed. The initial reduction of power should make it obvious that the aircraft will be unable to reach the runway in its full flap configuration. The immediate removal of flaps will cause a sink of nearly 200'. These negatives are soon seen to be offset by the flatter glide and extended glide path made possible by the absence of the flaps. When done smoothly, touchdown should occur about 2000' down the runway. Introduce this procedure shortly before solo. In 35 years this knowledge has prevented at least two off-airport landings by my soloing students at Concord CA..
http://www.whittsflying.com/web/page...e_of_Flaps.htm
I would add that no one has ever taught or shown me that, and I ain't tryin it on my own.
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I "may" know of someone who practices their EFATO and Glide Approaches by switching the engine off. Seems to work well for them. The added pressure of not having an idling engine appears to be directly proportional to making it onto the ground safely!
It's all good practicing it until you have 30 knots headwind - things change rapidly then!
It's all good practicing it until you have 30 knots headwind - things change rapidly then!
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Chimbu, yes Glider turn backs on cable release or break is 300 ft so is the base turn in a normal circuit. Also cct is flown very close in and the glide ration of the average training glider is twice that of a conventional powered aircraft.
Absolutist maybe, I was referring to powered aircraft and people turning into instant test pilots initiating low level turn backs.
The fact that you "got away with it" is testament to the existence of an element of lucky bravado, to celebrate that is in my view irresponsible.
Absolutist maybe, I was referring to powered aircraft and people turning into instant test pilots initiating low level turn backs.
The fact that you "got away with it" is testament to the existence of an element of lucky bravado, to celebrate that is in my view irresponsible.
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I don't think Chimbu's post displayed any elements of "lucky bravado".
The blanket “don’t turn back” is a good one to teach in my view, because it is very dangerous, and if you haven’t trained for it you’ll be putting yourself in a very poor situation. However, in the situation Chimbu described a logical series of steps were followed beginning with high altitude trials and progressing to a realistic situation.
This seems to me to give them the knowledge of under what weather conditions, at what height, and in what manner a turn back can be accomplished in their aircraft.
The blanket “don’t turn back” is a good one to teach in my view, because it is very dangerous, and if you haven’t trained for it you’ll be putting yourself in a very poor situation. However, in the situation Chimbu described a logical series of steps were followed beginning with high altitude trials and progressing to a realistic situation.
This seems to me to give them the knowledge of under what weather conditions, at what height, and in what manner a turn back can be accomplished in their aircraft.
If your aircraft has very good glide performance a turnback may be possible. As has been said gliders, PC-12 and some light aircraft with either good rate of climb after take-off or very high aspect wings will have a chance.
The problem has been those that have thought it possible in a Lance, Bonanza or similar that have stalled and crashed as a result. Some have been over open cattle country at the time which was little worse than a poorly maintained grass strip. The ATSB has many unfortunate acounts of attempted turnbacks which have resulted in loss of life. There are also many occurances of off airport landings which have been sucessful (light injuries with no loss of life).
Two major issues with a turnback are;
1. The much greater risk of loss of control.
2. Increased groundspeed at impact if any headwind was used on take-off.
In the case of the 30 kt headwind your ground speed at impact would be 60 kts greater turning back, that's assuming you were under control and used full flap and minimum touchdown speed. In a trainer your groundspeed at touchdown landing ahead in these circumstances would be less than 20 knots, even if you hit things it would be survivable.
Agreed
Its also good to remember that even in your aircraft a lot of things can change, especially if damage causing additional drag or airfoil deformation occured with the failure. Attempting a high wing loading maneuvre at low speed with damage to the airframe could result in anything.
The problem has been those that have thought it possible in a Lance, Bonanza or similar that have stalled and crashed as a result. Some have been over open cattle country at the time which was little worse than a poorly maintained grass strip. The ATSB has many unfortunate acounts of attempted turnbacks which have resulted in loss of life. There are also many occurances of off airport landings which have been sucessful (light injuries with no loss of life).
Two major issues with a turnback are;
1. The much greater risk of loss of control.
2. Increased groundspeed at impact if any headwind was used on take-off.
In the case of the 30 kt headwind your ground speed at impact would be 60 kts greater turning back, that's assuming you were under control and used full flap and minimum touchdown speed. In a trainer your groundspeed at touchdown landing ahead in these circumstances would be less than 20 knots, even if you hit things it would be survivable.
The blanket “don’t turn back” is a good one to teach in my view, because it is very dangerous, and if you haven’t trained for it you’ll be putting yourself in a very poor situation. However, in the situation Chimbu described a logical series of steps were followed beginning with high altitude trials and progressing to a realistic situation.
This seems to me to give them the knowledge of under what weather conditions, at what height, and in what manner a turn back can be accomplished in their aircraft.
This seems to me to give them the knowledge of under what weather conditions, at what height, and in what manner a turn back can be accomplished in their aircraft.
Its also good to remember that even in your aircraft a lot of things can change, especially if damage causing additional drag or airfoil deformation occured with the failure. Attempting a high wing loading maneuvre at low speed with damage to the airframe could result in anything.
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Just a little check on the mathematics, if you were to take of into wind ( normal practice) and say the wind was an average 15 knots at ground and given some shear say 18 knots at 500 ft.
So a take off at 60 knots will give a ground speed of 45 knots and then there is an acceleration to climb performance as the aircraft accelerates, then silence at 500 ft, now you have to contend with a turnback to a downwind of initial say 18 knots and if you make it on final of 15 knots into a very shortened available bit of runway at a ground speed of 75 knots assuming the approach was stable at 60 knots.
You are most assuredly in test pilot country, if you make it onto the runway , then you have to stop using a well out of spec braking system and potentially difficult runway surface.
On a 1000 metre bitumen runway this would be hazardous in the extreme, onto an 800 metre gravel ungraded strip tantamount to suicide.
This is all without considering Density altitude which could cramp your style much further and considerations of whether or not you are close to AUW.
So a take off at 60 knots will give a ground speed of 45 knots and then there is an acceleration to climb performance as the aircraft accelerates, then silence at 500 ft, now you have to contend with a turnback to a downwind of initial say 18 knots and if you make it on final of 15 knots into a very shortened available bit of runway at a ground speed of 75 knots assuming the approach was stable at 60 knots.
You are most assuredly in test pilot country, if you make it onto the runway , then you have to stop using a well out of spec braking system and potentially difficult runway surface.
On a 1000 metre bitumen runway this would be hazardous in the extreme, onto an 800 metre gravel ungraded strip tantamount to suicide.
This is all without considering Density altitude which could cramp your style much further and considerations of whether or not you are close to AUW.
Grandpa Aerotart
Lotta **** being posted on this thread - about par for the course for Pprune whenever a technique/technical question has been asked.
For starters any instructor that insists light piston engined aircraft should be flown on 'stabilised approaches' in the same vein as a heavy jet (fully configured at 500') needs belting around the ear 'ole.
A 'stabilised approach' in a Cessna/Piper/Beechcraft is one where the aircraft is slowly decelerating all the way around base/final, with configuration changes taking place at the ideal altitude/speed so that you arrive at 50' at 1.3vs minimum. Maybe a little faster for all the usual reasons.
Final flap selection should take place around 200-300'. If you don't need full flap land at partial flap - if for no other reason than curiosity
Power setting should be a lot less than is seen in 98% of flying school circuits.
Final approach path a steeper than a Papi/Vasis/ILS.
If you're teaching fully configured/1.3vs at 500' STOP INSTRUCTING.
If your instructor is insisting on anything like the above change instructor - if the new one is the same take your $ somewhere else.
The mere fact that above is recommended in a CASA document should be warning enough - most remaining CASA employees are unemployable career failures - the good ones give up and leave. They are the LAST people we should look to for guidance on how to fly light aircraft.
At ANY point on base/final you should be able to make the runway after an engine failure by no other expedient than merely NOT configuring ANYMORE.
That is what is meant by 'not taking the last stage of flap until you KNOW you can make the runway'. Mid base/750'/flaps 10 you should be able to make the runway if the engine fails. Base turning final/flap 20/500' you should be able to make the runway if the engine fails. Mid final/flap 30 you should be able to make the runway if the engine fails.
If a student is truly incapable of selecting a stage of flap, making a slight pitch adjustment and trimming at any altitude above 200' seriously suggest he take up kite flying.
I am serious. You instructors are there to teach people to FLY not manage (in the airline sense of 'manage') especially pre CPL training.
As to turn backs - well don't ya just love the twits who start spouting numbers that suggest its impossible.
"Well if you were taking off into a 30kt hwc..."
Ok hands up who has EVER taken off into a 30kt HWC let alone lately. I have 15000hrs and apart from the odd BIG day during the SE Tradewinds at Port Moresby I don't think I have ever. How did you manage to taxi your C172 to the runway without taking out a hangar/tied down aircraft?
If you did takeoff off into the teeth of this gale you would be still over the runway at 500' and, yes, if you turned back you would likely crash somewhere back along the final approach path for the runway...and I would laugh at you, ridicule you and call you a moron to your face.
If you killed yourself I would feel great satisfaction that you have removed yourself from the gene pool while feeling genuinely sad for any people you took with you.
If you try and turn back in an aeroplane you don't ABSOLUTELY know will do it - or without training and lots of practice - or in conditions where straight aheadish is a better bet - on the spur of the moment - or an engine failure after takeoff is a total surprise - or despite the fact you're incapable of consistently doing a gliding 45 degree bank angle turn at +/- 2-3 kts of the correct speed, just on the first nibble of buffet, at low altitude, BALANCED then see my gene pool comment above.
Seriously.
MOST pilots SHOULDN'T attempt a Turn Back in MOST aircraft MOST of the time.
But SOME aircraft can do it and a properly trained pilot with the requisite skills in one of THOSE aircraft should, I believe, have it in his bag of tricks. Jaba has only sat and watched (he did fly a few at altitude)...one day he might be in a position to add it to HIS bag of tricks. One day he MIGHT find himself in a situation where its an appropriate choice.
Knowing what I know about the Rv10 and with my general experience gliding this aircraft (not just yesterday) if I was departing YRED 07 and had an engine failure would I turn back or put the aircraft into Deception Bay?
You tell me. Note the first approach is a 'normal' glide approach from downwind at 1000'. On each glide approach, including the turn backs, the only things I am changing after engine 'failure' is prop pitch and flaps.
Sorry for the poor quality - youtube reduces the quality and it was late in the day with low light.
For starters any instructor that insists light piston engined aircraft should be flown on 'stabilised approaches' in the same vein as a heavy jet (fully configured at 500') needs belting around the ear 'ole.
A 'stabilised approach' in a Cessna/Piper/Beechcraft is one where the aircraft is slowly decelerating all the way around base/final, with configuration changes taking place at the ideal altitude/speed so that you arrive at 50' at 1.3vs minimum. Maybe a little faster for all the usual reasons.
Final flap selection should take place around 200-300'. If you don't need full flap land at partial flap - if for no other reason than curiosity
Power setting should be a lot less than is seen in 98% of flying school circuits.
Final approach path a steeper than a Papi/Vasis/ILS.
If you're teaching fully configured/1.3vs at 500' STOP INSTRUCTING.
If your instructor is insisting on anything like the above change instructor - if the new one is the same take your $ somewhere else.
The mere fact that above is recommended in a CASA document should be warning enough - most remaining CASA employees are unemployable career failures - the good ones give up and leave. They are the LAST people we should look to for guidance on how to fly light aircraft.
At ANY point on base/final you should be able to make the runway after an engine failure by no other expedient than merely NOT configuring ANYMORE.
That is what is meant by 'not taking the last stage of flap until you KNOW you can make the runway'. Mid base/750'/flaps 10 you should be able to make the runway if the engine fails. Base turning final/flap 20/500' you should be able to make the runway if the engine fails. Mid final/flap 30 you should be able to make the runway if the engine fails.
If a student is truly incapable of selecting a stage of flap, making a slight pitch adjustment and trimming at any altitude above 200' seriously suggest he take up kite flying.
I am serious. You instructors are there to teach people to FLY not manage (in the airline sense of 'manage') especially pre CPL training.
As to turn backs - well don't ya just love the twits who start spouting numbers that suggest its impossible.
"Well if you were taking off into a 30kt hwc..."
Ok hands up who has EVER taken off into a 30kt HWC let alone lately. I have 15000hrs and apart from the odd BIG day during the SE Tradewinds at Port Moresby I don't think I have ever. How did you manage to taxi your C172 to the runway without taking out a hangar/tied down aircraft?
If you did takeoff off into the teeth of this gale you would be still over the runway at 500' and, yes, if you turned back you would likely crash somewhere back along the final approach path for the runway...and I would laugh at you, ridicule you and call you a moron to your face.
If you killed yourself I would feel great satisfaction that you have removed yourself from the gene pool while feeling genuinely sad for any people you took with you.
If you try and turn back in an aeroplane you don't ABSOLUTELY know will do it - or without training and lots of practice - or in conditions where straight aheadish is a better bet - on the spur of the moment - or an engine failure after takeoff is a total surprise - or despite the fact you're incapable of consistently doing a gliding 45 degree bank angle turn at +/- 2-3 kts of the correct speed, just on the first nibble of buffet, at low altitude, BALANCED then see my gene pool comment above.
Seriously.
MOST pilots SHOULDN'T attempt a Turn Back in MOST aircraft MOST of the time.
But SOME aircraft can do it and a properly trained pilot with the requisite skills in one of THOSE aircraft should, I believe, have it in his bag of tricks. Jaba has only sat and watched (he did fly a few at altitude)...one day he might be in a position to add it to HIS bag of tricks. One day he MIGHT find himself in a situation where its an appropriate choice.
Knowing what I know about the Rv10 and with my general experience gliding this aircraft (not just yesterday) if I was departing YRED 07 and had an engine failure would I turn back or put the aircraft into Deception Bay?
You tell me. Note the first approach is a 'normal' glide approach from downwind at 1000'. On each glide approach, including the turn backs, the only things I am changing after engine 'failure' is prop pitch and flaps.
Sorry for the poor quality - youtube reduces the quality and it was late in the day with low light.
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pc-12 turnback clarification
The RFDS only teach turnbacks from 1000' agl. Below that your landing ahead. Personally if I can, I depart away from my destination so I set course overhead. Then if the engine fails on departure I have a chance of making it back.
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So this doesn't degrade into a Pissing Contest, I make this observation in support of my "Absolutist" position.
Can a turn back from 500 ft be successful, yes it can under very controlled circumstances by very experienced pilots who are current on type.
Should turn backs from 500 ft be done, a whole different argument and to that I say the answer is NO.
Can a turn back from 500 ft be successful, yes it can under very controlled circumstances by very experienced pilots who are current on type.
Should turn backs from 500 ft be done, a whole different argument and to that I say the answer is NO.
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theory is for girls
All you experts can keep your advice,
I think ill look at the number of engine failures on final vs number of incidents due config changes/ runway overruns
and then make my own mind up on whats important.
Mouse
I think ill look at the number of engine failures on final vs number of incidents due config changes/ runway overruns
and then make my own mind up on whats important.
Mouse
