Recovering from a FLAT spin.
Let's start with some basic physics of the spin:
http://oea.larc.nasa.gov/PAIS/Concep...echnology.html from NASA
http://www.ozaeros.com/spin/ostivxx.html from Ozaeros
Then some data - not easy to find actual data online for the effect of power so let's start with power off. One of the classic NASA reports for indicating which aeroplanes are best to stay away from is TP 1009.
http://ntrs.nasa.gov/archive/nasa/ca...1977026167.pdf There are other reports showing the effect of aileron on recovery.
From memory, Birhle did some powered model tests in the early '80's but reports are not available electronically. http://www.bihrle.com/site/bibliography.html
Pitching moments are a lot more complex than a simple thrust or drag multiplied by a moment arm. First of all, there is the effect of the slipstream on flow at the tail. Secondary effects through gyroscopic moments effect spin rate and sideslip which further change the pitching moment per http://www.ozaeros.com/spin/Spinfig4.jpg
Interesting video of NASA's test of the Grumman Trainer showing attempts to recover from a flat spin. http://www.allaboutguppys.com/spin/spin.mpg
Finally, some training videos including the flat spin in an Extra 300.
http://www.fcitraining.com/video.htm
Back to the question:
My answer is qualified by a few assumptions - you're endorsed on spins, in an airplane approved for intentional spinning and loaded within limits. Follow the method in the POH for the type. If that doesn't work its most likely that you messed up so check everything, go back and try again. That requires explanation, better done face to face which is where greeners and 7gcbc came in.
http://oea.larc.nasa.gov/PAIS/Concep...echnology.html from NASA
http://www.ozaeros.com/spin/ostivxx.html from Ozaeros
Then some data - not easy to find actual data online for the effect of power so let's start with power off. One of the classic NASA reports for indicating which aeroplanes are best to stay away from is TP 1009.
http://ntrs.nasa.gov/archive/nasa/ca...1977026167.pdf There are other reports showing the effect of aileron on recovery.
From memory, Birhle did some powered model tests in the early '80's but reports are not available electronically. http://www.bihrle.com/site/bibliography.html
Pitching moments are a lot more complex than a simple thrust or drag multiplied by a moment arm. First of all, there is the effect of the slipstream on flow at the tail. Secondary effects through gyroscopic moments effect spin rate and sideslip which further change the pitching moment per http://www.ozaeros.com/spin/Spinfig4.jpg
Interesting video of NASA's test of the Grumman Trainer showing attempts to recover from a flat spin. http://www.allaboutguppys.com/spin/spin.mpg
Finally, some training videos including the flat spin in an Extra 300.
http://www.fcitraining.com/video.htm
Back to the question:
What actions would you take to attempt a recovery from a flat spin.
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From Flight Unlimited by Eric Muller and Annette Carson - paraphrased.
Throttle closed - most important
Stick back and 'in' to the spin.
Opposite rudder.
When the rotation stops bring the stick central and neutral, recover, take pants to cleaners !
The Muller/Beggs recovery works for nearly all standard aeroplanes and spins and is let go of the stick and rudder, press fully on the rudder pedal that floats toward you, as the rotation stops, catch the stick as it moves from rear left or right to central.
Throttle closed - most important
Stick back and 'in' to the spin.
Opposite rudder.
When the rotation stops bring the stick central and neutral, recover, take pants to cleaners !
The Muller/Beggs recovery works for nearly all standard aeroplanes and spins and is let go of the stick and rudder, press fully on the rudder pedal that floats toward you, as the rotation stops, catch the stick as it moves from rear left or right to central.
Dancing with the devil, going with the flow... it's all a game to me.
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Originally Posted by DFC
I have flown at least 3 types that pitch down when power is applied. The pitching direction depends on the position of the engine and the thrust line and drag line.
Regards,
DFC
Regards,
DFC
VFE.
Flight International mag of 28 October 1078 had an article on Cessna spinning per a Cessna test pilot. Some extracts relevant to this thread:
Hand off recoveries in the 152: "certainly recovered .. after two turns but lost as much height in the process as if it had spun for another four turns before recovering."
Effect of ailerons in the 152: "Even small amounts of aileron deflection into the spin may increase the rotation rate and prolong recovery." i.e aileron into the spin makes this one go flatter.
One of Gene Beggs' articles on spinning noted that the Beggs/Mueller method failed to recover a 150 - he related a discussion he had with Bill Kershner on the subject then confirmed it himself.
Worth repeating - read the POH for the type - spin characteristics differ significantly between one type and another.
Hand off recoveries in the 152: "certainly recovered .. after two turns but lost as much height in the process as if it had spun for another four turns before recovering."
Effect of ailerons in the 152: "Even small amounts of aileron deflection into the spin may increase the rotation rate and prolong recovery." i.e aileron into the spin makes this one go flatter.
One of Gene Beggs' articles on spinning noted that the Beggs/Mueller method failed to recover a 150 - he related a discussion he had with Bill Kershner on the subject then confirmed it himself.
Worth repeating - read the POH for the type - spin characteristics differ significantly between one type and another.
Not Good Airline Material
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VFE,
I take it you've managed to control any pitch-up tendencies with the application of full power during stall recoveries in the 152 without too much difficulty?
I take it you've managed to control any pitch-up tendencies with the application of full power during stall recoveries in the 152 without too much difficulty?
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KISS
Originally Posted by VFE
So power causes the aircraft to pitch down eh? How's that work then chief?
VFE.
VFE.
People - Keep it simple stupid!
Throttle back, neutralise stick, full opposite rudder.
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The Muller/Beggs recovery works for nearly all standard aeroplanes and spins and is let go of the stick and rudder, press fully on the rudder pedal that floats toward you, as the rotation stops, catch the stick as it moves from rear left or right to central.[/quote]
It doesn't on S2B.
You have to close the power put IN SPIN AILERON and then opposite rudder and forward stick.
Power and outstpin airleron only flatter and accelerate spins.
It doesn't on S2B.
You have to close the power put IN SPIN AILERON and then opposite rudder and forward stick.
Power and outstpin airleron only flatter and accelerate spins.
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Originally Posted by javelin
The Muller/Beggs recovery works for nearly all standard aeroplanes and spins and is let go of the stick and rudder, press fully on the rudder pedal that floats toward you, as the rotation stops, catch the stick as it moves from rear left or right to central.
In my experience (A2 RAF JP QFI and 2 years of S2As with Rothmans) flat spins were induced by applying power. If an aircraft spins flat without power you shouldn't be spinning it deliberately (and it's definitely not a 'standard aircraft' nor a 'standard spin').
My suggestion for recovery from said flat spin would be:
- Close throttle and hold stick neutral
- If time permits, let spin stabilise then 'standard' recovery:
- Full rudder to oppose the turn (as indicated by the turn needle)*
- Pause (approx 2 seconds)
- Move stick smoothly forward until rotation stops
- Centralise rudder
- Recover from dive
Of course, I agree with Greeners - go to a reputable organisation and get proper training. Also find out, if possible, what idiosyncrasies your particular type has with regard to spinning and recovery (e.g. use of In/Out-spin aileron, Pause or not, etc.).
Regards,
rts
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[quote=The Muller/Beggs recovery works for nearly all standard aeroplanes and spins and is let go of the stick and rudder, press fully on the rudder pedal that floats toward you, as the rotation stops, catch the stick as it moves from rear left or right to central.[/quote]
Beggs works perfectly especially on the S2A and S2B, has done for many years. Upright, inverted, flat, accelerated, the lot.
Excluding competition spins of course, in an unintentional spin this assumes you know which way is up or down, which direction you are spinning and which way the yaw and roll is, and if you are in a true FLAT ( I mean developed accidental flat spin - which was pointed out as to be exceptionally rare), you would have power on and in a pitts the rate of rotation would be be brisk, with inspin (will only lower the nose) or fwd stick incorrectly timed with application of opposite rudder (assuming you pick the correct one) in the "heartbeat" moment, you'd find yourself in a crossover.
Curtis Pitts rarely endorsed anything, however a letter inside the first page of Gene Beggs book "Spins in the Pitts Special" is about as close as you get, and that book teaches the hand's off method.
Originally Posted by lc_aerobatics
It doesn't on S2B.
You have to close the power put IN SPIN AILERON and then opposite rudder and forward stick.
Power and outstpin airleron only flatter and accelerate spins.
You have to close the power put IN SPIN AILERON and then opposite rudder and forward stick.
Power and outstpin airleron only flatter and accelerate spins.
Beggs works perfectly especially on the S2A and S2B, has done for many years. Upright, inverted, flat, accelerated, the lot.
Excluding competition spins of course, in an unintentional spin this assumes you know which way is up or down, which direction you are spinning and which way the yaw and roll is, and if you are in a true FLAT ( I mean developed accidental flat spin - which was pointed out as to be exceptionally rare), you would have power on and in a pitts the rate of rotation would be be brisk, with inspin (will only lower the nose) or fwd stick incorrectly timed with application of opposite rudder (assuming you pick the correct one) in the "heartbeat" moment, you'd find yourself in a crossover.
Curtis Pitts rarely endorsed anything, however a letter inside the first page of Gene Beggs book "Spins in the Pitts Special" is about as close as you get, and that book teaches the hand's off method.
Last edited by precession; 16th Aug 2006 at 10:53.
