Power-On vs Power-Off Stall Speed

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Recovery from a spin is power off, opposite rudder, nose down right?

P - Power to Idle
A - Ailerons Neutral
R - Rudder Opposite of the Spin
E - Elevator Forward

One of the biggest killers of private pilots is the turn from base to final in the traffic partern. Of course at that altitude you are probably not going to recover before becoming a crater in the ground. And since you have to be stalled in order to spin, they teach you to recognize a stall so that you won't stall and spin the aircraft, and they teach you how to properly recover a stall so that you do not enter a spin. Personally I think spin recovery should still be taught.
 
P - Power to Idle
A - Ailerons Neutral
R - Rudder Opposite of the Spin
E - Elevator Forward
That's a good acronym...
Personally I think spin recovery should still be taught.
I agree -- it's a disservice to anybody who wants to fly safe.

In straight wing plane yes. In the Eagle not.
Well, as I understand it, in a jet you'd want to push the power up since there's no torque or p-factor right?
We eventually got a spin display which included splitting throttles against the spin in addition to flight control inputs.
Splitting the throttles? Like push one up and the other back to counter the yaw from the spin?
 
The above spin recovery is good for a typical trainer which may be spin resistant enough that just letting go of the controls may cause recovery. Many of the high HP WWII fighters had really bad spin manners, especially if more than a couple of turns were developed. Other flight manuals may say "punch out if below 10,000' or some equally helpful pean. High lateral rotational inertia can contribute to roll coupling and other undesirable effects.
 
I always felt rather privileged to have as my instructor (mid 70's) an unlimited aerobatic pilot who not only trained me in spins but also in many other exciting maneuvers that kept there from occurring any "what now" moments in a long flying career.

Cubs, yes have a bad history of low altitude stall spin accidents. Apparently the installation of VG's helps this a lot, though my cub does not have them (Makes installation of wing covers difficult). Not sure they are too useful on float planes except in the case of ham fisted maneuvering.
 
When first learning to fly I had issues with stalls, was always worried about spinning.
I was too dumb and too cocky to be scared of stalls and spins; the very sort of student I later came to hate. The Navy Flying Club where I learned was really hard core on spin prevention, and had a heavy emphasis on control coordination and yaw awareness right from lesson one. Incidentally, I learned in 1970, and spins had been gone from the curriculum for some time at that point. Most of my instructors had never had to do them.
The crusty old Chief Petty Officer who taught me slow flight and stalls was the best pilot and teacher I had ever shared a cockpit with in my young life. Nothing could go wrong with him onboard; IT WOULDN'T DARE! As he demonstrated maneuvers and as I tried to duplicate them, he talked to the airplane in his laid-back southern drawl like he was calming a skittish horse, always managing to indirectly alert me of any missteps on my part.
He told me he couldn't demand that I do spin training, but if I decided not to, there were plenty of other instructors in the club I could fly with. We did do the training, and it was a piece of cake (and a blast, to boot!).
Cheers,
Wes
 
For determining corner velocity, you'd compute power on stall correct?
NO! Published power on stall speeds are predicated on 1 G, straight and level flight. Corner velocity is based on a high G turning situation; a highly accelerated stall, typically multiples and then some, of the published power-on stall speed.
Cheers,
Wes
 
Of course varies a lot, maneuvering flaps and whatnot, but minimum turn radius speed will be somewhere near 1.5 VSO. However the typical piston fighter will bleed energy quite quickly when maneuvering at this speed. Energy deficit is typically why any sustained "dogfight" wound it's way down toward the deck.
 
That's a good acronym...
I agree -- it's a disservice to anybody who wants to fly safe.

Well, as I understand it, in a jet you'd want to push the power up since there's no torque or p-factor right?
Splitting the throttles? Like push one up and the other back to counter the yaw from the spin?

Zipper,

In the Eagle we pulled the throttles out of AB /afterburner probably for limiting the chance of having a engine stall or stag. Remember the airflow over and into the intakes during a spin is very corrupted, which could induce motor anomaly's. Also spins can be very disorienting, with misdiagnosis of direction being a serious threat. This was before the spin display.

Second, after the spin display was introduced they added putting one engine into AB , against the spin to help with recovery.

The Eagle was difficult to spin. It took misrigged flight controls, fuel imbalance, or pilot mishandling. I flew it long enough to realize fuel imbalances were occurring if I had to put aileron trim in after the external tanks were dry.

Rigging could go out, but didn't that often. Mishandling did happen to, but not bad enough to put one in a spin very often. They were rare in the Eagle.

Cheers,
Biff
 
Regarding spins etc. in the Mig-23 series I have read the vertical white line down the inst panel is there to center the stick in event of a spin and wait. I have seen this in a Mig-17 also. The Mig-23 has an automatic throttle retarding system to prevent too rapid throttle back at high speed. If speed is reduced too rapidly near max speed, uncontrollable pitch up occurs. This is what killed a Colonel about to retire and wanted to fly a Mig-23. He went to TTR but wouldn't listen to preflight advise and when he attempted to throttle back from highspeed, thought a malfunction occurred and was killed during ejection at high speed. This was before USAF admitted having Migs but the newspaper article confirmed rumors for me. The later book "Red Eagles" filled in details.
 
NO! Published power on stall speeds are predicated on 1 G, straight and level flight. Corner velocity is based on a high G turning situation; a highly accelerated stall, typically multiples and then some, of the published power-on stall speed.
Would a better approximation be to simply use the power-off stall x sqrt*g-load? It probably wouldn't be perfect, but...
 
Regarding spins etc. in the Mig-23 series I have read the vertical white line down the inst panel is there to center the stick in event of a spin and wait. I have seen this in a Mig-17 also. The Mig-23 has an automatic throttle retarding system to prevent too rapid throttle back at high speed. If speed is reduced too rapidly near max speed, uncontrollable pitch up occurs. This is what killed a Colonel about to retire and wanted to fly a Mig-23. He went to TTR but wouldn't listen to preflight advise and when he attempted to throttle back from highspeed, thought a malfunction occurred and was killed during ejection at high speed. This was before USAF admitted having Migs but the newspaper article confirmed rumors for me. The later book "Red Eagles" filled in details.

If supersonic in the Eagle the engines will not go below military power until subsonic IIRC.

Probably not that uncommon.

Cheers,
Biff
 
There was an aerodynamic analysis posted on here discussing the Spitfire, FW190 (and the P-51 I believe). The Fw190 had washout on the wing but not at the extremities (from memory circa 1m or so). In an increasingly aggressive power on turn the distribution of lift across the wing narrowed until it is just a small section of the wing was supporting the A/C, when that is insufficient to support the aircraft one wing would stall quickly resulting in a violent summersault out of the turn, this is completely at odds with its behaviour in take off and landing.
 
the distribution of lift across the wing narrowed until it is just a small section of the wing was supporting the A/C, when that is insufficient to support the aircraft one wing would stall quickly resulting in a violent summersault
Putting a twist in the wings to cause them to stall progressively from root to tip is a great way to maintain aileron control as long as possible, but leaves the plane supported by its wingtips at the end, and susceptible to the slightest asymmetry inducing a violent departure. The antidote to this is SUPPOSED to be to design a layout that will cause the disturbed airflow from the stalled wing roots to gradually blank the elevator until it can no longer maintain the angle of attack and the aircraft pitches "down". This SHOULD alleviate that precarious "suspended by the wingtips" situation before it turns disastrous.
Sounds like ol' Kurt might have missed something here in his quest for ultimate ACM performance.
Cheers,
Wes
 
Putting a twist in the wings to cause them to stall progressively from root to tip is a great way to maintain aileron control as long as possible, but leaves the plane supported by its wingtips at the end, and susceptible to the slightest asymmetry inducing a violent departure. The antidote to this is SUPPOSED to be to design a layout that will cause the disturbed airflow from the stalled wing roots to gradually blank the elevator until it can no longer maintain the angle of attack and the aircraft pitches "down". This SHOULD alleviate that precarious "suspended by the wingtips" situation before it turns disastrous.
Sounds like ol' Kurt might have missed something here in his quest for ultimate ACM performance.
Cheers,
Wes
Aerodynamics isn't my "bag" lol I would have to find the article. As I understand it, the aircraft is supported by a smaller and smaller section of the wings. Eventually a point is reached where it doesn't and one wing stalls with no warning sending the plane tumbling out of the turn. here it is but took ages to load http://www.wwiiaircraftperformance.org/mustang/Lednicer_Fighter_Aerodynamics.pdf
 
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