"Inverted Stall"?
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"Inverted Stall"?
Had a bit of a chat before the fog cleared today and I was told about an "event" yesterday where an endorsee was getting an endorsement on a six cylinder aircraft and had a little incident with "the stall".
I know not if this was clean or dirty, power on or power off, but suspect it was the simple type.
The endorsee, so the story goes, sawed at the ailerons a bit, and the result was the aircraft dropping a wing and then inverting. Now from what i was told, the aircraft didn't enter a spin, it just sort of made like a leaf, falling down inverted. Until the instructor applied a boot full of rudder in some direction and the aircraft came upright and all was the ticketyboo, even if the Altimeter said 400 feet.
Question: Is there such a thing as an inverted stall?
And no, this is not a wind up, unless certain people have conspired to pull my leg.
I know not if this was clean or dirty, power on or power off, but suspect it was the simple type.
The endorsee, so the story goes, sawed at the ailerons a bit, and the result was the aircraft dropping a wing and then inverting. Now from what i was told, the aircraft didn't enter a spin, it just sort of made like a leaf, falling down inverted. Until the instructor applied a boot full of rudder in some direction and the aircraft came upright and all was the ticketyboo, even if the Altimeter said 400 feet.
Question: Is there such a thing as an inverted stall?
And no, this is not a wind up, unless certain people have conspired to pull my leg.
YesTAM
Yes there is such a thing but for the exception of high end aero aircraft are hard to get in and even harder to stay in. I find it difficult to believe the story as told. My guess is that the aircraft entered a spin and if the story can be believed a little, a late recovery.
Yes there is such a thing but for the exception of high end aero aircraft are hard to get in and even harder to stay in. I find it difficult to believe the story as told. My guess is that the aircraft entered a spin and if the story can be believed a little, a late recovery.
Aeroplanes can indeed drop a wing, even going inverted, but that's not an inverted stall.
Just as you stall an aircraft by exceeding it's critical angle of attack by pulling back on the control column, you can exceed it the opposite way by pushing hard forward as well.
Inverted spins for example, are easily entered by flying upside down, slowing down, and pushing forward on the stick whilst applying a bootful or rudder. That pushing forward creates a greater negative angle of attack that will no longer support the weiaght of the aircraft. For a very brief period in time the world suddenly looks great - right way up - all normal, before the spin continues earthwards. Great fun - try it with an experienced aerobatic instructor in a suitable aircraft !!
Just as you stall an aircraft by exceeding it's critical angle of attack by pulling back on the control column, you can exceed it the opposite way by pushing hard forward as well.
Inverted spins for example, are easily entered by flying upside down, slowing down, and pushing forward on the stick whilst applying a bootful or rudder. That pushing forward creates a greater negative angle of attack that will no longer support the weiaght of the aircraft. For a very brief period in time the world suddenly looks great - right way up - all normal, before the spin continues earthwards. Great fun - try it with an experienced aerobatic instructor in a suitable aircraft !!
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Yes, there is such a thing as an inverted stall. Yes, there is such a thing as an inverted spin.
But I gotta agree with 404.
I think either (a) someone is telling you stories, or (b) the story teller got such a fright when said aircraft rolled onto its back that they had no real idea of events that followed.
R
But I gotta agree with 404.
I think either (a) someone is telling you stories, or (b) the story teller got such a fright when said aircraft rolled onto its back that they had no real idea of events that followed.
R
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A slight thread subject digression but clearly remember watching a TV program of a Farnborough Air Show back in the early 70s and seeing an Italian Test Pilot holding a Macchi Jet Trainer in a sustained inverted spin. And recovered from same.
Most impressive!
Most impressive!
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Inverted spins
If anyone is interested, here are a couple of videos I found quickly on youtube.
This one is a video taken from the aircraft as it performs an inverted spin:
http://www.youtube.com/watch?v=klI40PzlQAM
This one is a video of the aircraft. Its only short but shows the entry into an inverted spin pretty well.
http://www.youtube.com/watch?v=YnulcYFu-Ss
This one is a video taken from the aircraft as it performs an inverted spin:
http://www.youtube.com/watch?v=klI40PzlQAM
This one is a video of the aircraft. Its only short but shows the entry into an inverted spin pretty well.
http://www.youtube.com/watch?v=YnulcYFu-Ss
The Kiwis used to demonstrate and practise inverted spins in both their propellor and jet trainers, just a few years ago. Not in the mighty Sioux though... does an autorotation count?
First solo trip outside the circuit. Ardmore 1967. Victa 100. 17 hours total time.
Fearless hero tried a roll but chickened out at 90 degrees bank.
Loops look easy, lets try that. Had watched the instructors do it. Doesn't look too hard. 123 knots entry, pull up over the top. KEEP PULLING, full back stick.
Yes there is an inverted stall, and if you hold it in it rapidly becomes an inverted spin.
Hightail it back to base. Sit in aircraft for 10 minutes while jelly legs solidify enough to climb out.
Only once.
Maui
Fearless hero tried a roll but chickened out at 90 degrees bank.
Loops look easy, lets try that. Had watched the instructors do it. Doesn't look too hard. 123 knots entry, pull up over the top. KEEP PULLING, full back stick.
Yes there is an inverted stall, and if you hold it in it rapidly becomes an inverted spin.
Hightail it back to base. Sit in aircraft for 10 minutes while jelly legs solidify enough to climb out.
Only once.
Maui
Capt Fathom
I really have no idea what it was. I had a total of 17 hours and didn't have a clue. All I know was that I was coming over the top and had pulled to full backstick. Then all hell broke loose. Fortunately after a short time I relaxed everything and found the rotation slowing and me pointing earthwards in a less than pleasant attitude.
Naturally,at the time I could not discuss it with anyone, and have assumed to this day that what occured was a stall from an inverted position, which then started to rotate. Fortunately the Victa is one of those aircraft that you really have to try, to get it to spin. Let go of everything and it will stop itself, albeit, in a nose low attitude.
MAui
I really have no idea what it was. I had a total of 17 hours and didn't have a clue. All I know was that I was coming over the top and had pulled to full backstick. Then all hell broke loose. Fortunately after a short time I relaxed everything and found the rotation slowing and me pointing earthwards in a less than pleasant attitude.
Naturally,at the time I could not discuss it with anyone, and have assumed to this day that what occured was a stall from an inverted position, which then started to rotate. Fortunately the Victa is one of those aircraft that you really have to try, to get it to spin. Let go of everything and it will stop itself, albeit, in a nose low attitude.
MAui
Silly Old Git
Maui I would suggest the Victa just gave up flying and did its usual... FLOOOMPH !....oil-canning carry-on that would have frightened the sh*t out of a 17 hour student, and until you unfroze on the backstick it wudda kept doing it
I have flown pretty well all the Victas from the 100 to 150 CSU (40 years ago mind)
None of them had any inclination to spin properly but were a superb little trainer that would not be out of place today
I have flown pretty well all the Victas from the 100 to 150 CSU (40 years ago mind)
None of them had any inclination to spin properly but were a superb little trainer that would not be out of place today
Part of my aero rating in a 152 involved doing a loop from straight and level, full noise, no dive to pick up speed. Going over the top everything very mushy, pretty much zero on the asi, a wee buffet, with stall warning. Check forward a bit..woops, bit too much, another wee buffet (this time without the stall warning) check back a bit again, picking up speed, now, normal recovery. Reckon that second buffet was the announcement of an inverted stall.
Subsequently consider my instructor's wish for me to do a loop without diving a bit first a very valid and probably justifiable attempt to get me to stop being so ham fisted.
Subsequently consider my instructor's wish for me to do a loop without diving a bit first a very valid and probably justifiable attempt to get me to stop being so ham fisted.
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I thought that an inverted stall was one when the stall was fully developed with the stick forward. Falling off the top of a loop with the stick full back still produced a normal stall even when it was entered from the inverted position. Are my assumtions correct?
I thought that an inverted stall was one when the stall was fully developed with the stick forward. Falling off the top of a loop with the stick full back still produced a normal stall even when it was entered from the inverted position. Are my assumptions correct?
In the case of falling off a loop, stick back, it will be a normal stall, likely developing into a spin.
Ever tried a roll off the top and bu@@ered it up? I have, and done the beginning of an inverted spin. Didn't like it much, so centered everything pdq and let the 152 recover itself.
Would be interesting to hear from one of the aerobatic gurus that hang out in here.
Been a few years since I have done any aerobatics in a C152, but I suspect that you would have to work hard to get one into an inverted spin and even harder to keep it there. My recollection is that, loaded appropriately for aeros, you cannot get enough down (up) elevator to stall a C152 from an inverted glide (the engine won't run for long). Maybe, as pointed out above, you might do it from a messed up roll-off-the-top. However, I don't recall the C152 being a ready "spinner" without plenty of rudder, with the entry being pretty messy without some aileron, and you would really have to screw up a roll-off-the-top to get enough yaw going. Perhaps lots of forward stick, a bit of yaw and lots of aileron would do it.
Dr
PS: Before someone jumps all over me - I AM NOT ADVOCATING THAT ANYONE SHOULD TRY TO DO AN INVERTED SPIN IN A C152 Aerobat.
Been a few years since I have done any aerobatics in a C152, but I suspect that you would have to work hard to get one into an inverted spin and even harder to keep it there. My recollection is that, loaded appropriately for aeros, you cannot get enough down (up) elevator to stall a C152 from an inverted glide (the engine won't run for long). Maybe, as pointed out above, you might do it from a messed up roll-off-the-top. However, I don't recall the C152 being a ready "spinner" without plenty of rudder, with the entry being pretty messy without some aileron, and you would really have to screw up a roll-off-the-top to get enough yaw going. Perhaps lots of forward stick, a bit of yaw and lots of aileron would do it.
Dr
PS: Before someone jumps all over me - I AM NOT ADVOCATING THAT ANYONE SHOULD TRY TO DO AN INVERTED SPIN IN A C152 Aerobat.
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Yes there is an inverted stall (and subsequently spin!).
But it is NOT difficult to get into!!
Incorrect stall/spin recovery technique can quite easily cause an upright spin to crossover into an inverted spin.
Consult your POH for correct recovery technique for your particular aircraft, but in general remember
Power off
Ailerons neutral
Rudder against the spin
Elevator through neutral
Remember you need to Cut the throttle, Stop the yaw, Stop the stall IN THAT ORDER. Any other order and you risk accelerating, flattening, or reversing the spin...and unless you know what you are doing any of these will be disorienting at the least and deadly at worst!!
If you want to explore any of these spins then I suggest getting hold of an aerobatic instructor and aircraft...don't try them yourself...you can end up in deep "doo doos" very quickly...
Upset and spin recovery should be something that every pilot experiences...it is a blast and quite enjoyable if done in the right aircraft with the right training, and can only make a better pilot of you.
But it is NOT difficult to get into!!
Incorrect stall/spin recovery technique can quite easily cause an upright spin to crossover into an inverted spin.
Consult your POH for correct recovery technique for your particular aircraft, but in general remember
Power off
Ailerons neutral
Rudder against the spin
Elevator through neutral
Remember you need to Cut the throttle, Stop the yaw, Stop the stall IN THAT ORDER. Any other order and you risk accelerating, flattening, or reversing the spin...and unless you know what you are doing any of these will be disorienting at the least and deadly at worst!!
If you want to explore any of these spins then I suggest getting hold of an aerobatic instructor and aircraft...don't try them yourself...you can end up in deep "doo doos" very quickly...
Upset and spin recovery should be something that every pilot experiences...it is a blast and quite enjoyable if done in the right aircraft with the right training, and can only make a better pilot of you.
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...actually...one of the easiest methods of entering an inverted spin (in a Pitts S2B) is exactly the same way of entering an upright spin.....
reduce throttle
bleed speed off whilst holding altitude
at the buffet/nose drop push full forward on the stick while introducing yaw (boot full of rudder) and viola (stringed instrument!!)....INVERTED SPIN
So all those recovering from the stall with a rapid push on the stick (rather than just reducing back pressure) actually risk entering test pilot territory!!!
BE GENTLE!!
reduce throttle
bleed speed off whilst holding altitude
at the buffet/nose drop push full forward on the stick while introducing yaw (boot full of rudder) and viola (stringed instrument!!)....INVERTED SPIN
So all those recovering from the stall with a rapid push on the stick (rather than just reducing back pressure) actually risk entering test pilot territory!!!
BE GENTLE!!
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It sounds like the departure from the top of the inside loop was essentially a snap roll. I did something similar recently in a Giles 202 when I managed a complete 360 degree snap at the top of the loop, then carried on with the loop. This is technically known as an "Avalanche".
I'd like to claim it was skill but in fact I just heavy handed - the Giles has such light controls (and I fly a Pitts S-2C) that I pulled fractionally too hard and tip stalled...
But if the stick is back, it should be an upright, not an inverted spin...
I'd like to claim it was skill but in fact I just heavy handed - the Giles has such light controls (and I fly a Pitts S-2C) that I pulled fractionally too hard and tip stalled...
But if the stick is back, it should be an upright, not an inverted spin...
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Maui
Mate if you are anything like my ham-fisted students (and ham-fisted self 
) you would have had a fair bit of slipstream-induced yaw at the apex of your "loop".
I don't have massive experience in Victas but they do flick roll very nicely in exactly the circumstances you describe - and as someone said, so long as the stick is held back she'll jus' keep rotating 
) you would have had a fair bit of slipstream-induced yaw at the apex of your "loop".I don't have massive experience in Victas but they do flick roll very nicely in exactly the circumstances you describe
- and as someone said, so long as the stick is held back she'll jus' keep rotating