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BruceAir
11-23-2012, 08:51 PM
I've posted several new short videos on my YouTube channel (http://www.youtube.com/user/BruceAirFlying). They're from recent flights in my Extra 300L, and they demonstrate coordinated (non-yawing) accelerated stalls (http://www.youtube.com/watch?v=2UhaYJuWbUY&list=UUF6oQpkwU9DaCOQpyIu1v0A&index=7&feature=plcp) from turns, stalls while in skidding and slipping (yawing) turns (http://www.youtube.com/watch?v=rYHNO2kvuZI&list=UUF6oQpkwU9DaCOQpyIu1v0A&index=6&feature=plcp), and an intentional spin (http://www.youtube.com/watch?v=qxuLCoPxXuo&list=UUF6oQpkwU9DaCOQpyIu1v0A&index=5&feature=plcp) from a slow-deceleration stall. I also included a quiz of sorts--demonstrations of skidding and slipping stalls (http://www.youtube.com/watch?v=wioGN2SPGps&list=UUF6oQpkwU9DaCOQpyIu1v0A&index=4&feature=plcp) in which, based on what you observe turning the turns, you try to predict which way the stall will break.

Here's one of the videos as a sample.


http://www.youtube.com/watch?v=rYHNO2kvuZI&feature

-Bruce
www.BruceAir.com (http://www.BruceAir.com)
http://bruceair.wordpress.com/

danielfindling
11-24-2012, 05:57 AM
I have my private with an hour or two in aerobatic airplanes many years ago. Great videos. I really like the aggressive slip from a bank with the spin in the opposite direction. I have a question. I noticed that your technique varies from the PARE (power off, aileron neutral, opposite rudder and elevator briskly forward). It appears to me that your recovery was more like PEAR. Power, elevator (to get the wings flying) aileron neutral, rudder opposite. Am I following you correctly? It seems logical that you need to get the wings flying again before recovery. Would you use your technique in a plane like I fly - a Cessna 140A?

Thanks,

Daniel Findling

BruceAir
11-24-2012, 07:49 AM
To recover from a stall, the first step should be reducing angle of attack (i.e., relaxing back pressure or applying forward pressure on the yoke or stick). As I show in the videos, getting the wing flying again stops or dramatically reduces the rolling tendency. Many pilots that I fly with are most concerned about the roll, and they try to stop it with opposite aileron before they break the stall. Doing that aggravates the stall, perhaps allowing it to develop into an incipient spin.

If a spin starts to develop, the PARE sequence is the best recovery technique, barring specific instructions to the contrary from the manufacturer of your aircraft.

For more information, see Chapter 4 of the Airplane Flying Handbook (http://www.faa.gov/library/manuals/aircraft/airplane_handbook/) and Rich Stowell's (http://www.richstowell.com/) excellent book, Stall/Spin Awareness (http://www.richstowell.com/store/books/book-stallspin-awareness/). APS (http://www.apstraining.com/) also has an excellent article, Cross-Controlled Stalls – The Skidded Turn (http://www.apstraining.com/2009/traffic-pattern-stalls/), available on their website. As APS notes:


The recommended stall recovery (and the one that APS teaches) is: Push - Power - Rudder - Roll - Climb



You can also find more information on the Stall/Spin page (http://www.bruceair.com/stall-spin/stall-spin.htm) at my website.

Check 6
11-24-2012, 07:57 PM
Excellent! Thanks for sharing. :thumbsup:

danielfindling
11-25-2012, 03:47 PM
To recover from a stall, the first step should be reducing angle of attack (i.e., relaxing back pressure or applying forward pressure on the yoke or stick). As I show in the videos, getting the wing flying again stops or dramatically reduces the rolling tendency. Many pilots that I fly with are most concerned about the roll, and they try to stop it with opposite aileron before they break the stall. Doing that aggravates the stall, perhaps allowing it to develop into an incipient spin.If a spin starts to develop, the PARE sequence is the best recovery technique, barring specific instructions to the contrary from the manufacturer of your aircraft. For more information, see Chapter 4 of the Airplane Flying Handbook (http://www.faa.gov/library/manuals/aircraft/airplane_handbook/) and Rich Stowell's (http://www.richstowell.com/) excellent book, Stall/Spin Awareness (http://www.richstowell.com/store/books/book-stallspin-awareness/). APS (http://www.apstraining.com/) also has an excellent article, Cross-Controlled Stalls – The Skidded Turn (http://www.apstraining.com/2009/traffic-pattern-stalls/), available on their website. As APS notes:You can also find more information on the Stall/Spin page (http://www.bruceair.com/stall-spin/stall-spin.htm) at my website.

Thanks for the clarification. At :56 sec. in the video (2:53 remaining) you describe the recovery from the incipient spin by stopping the stall first ("as soon as we stop the stall the rotation stops") with elevator - That was the source of my confusion. Am i correct that when you were inverted and beginning to roll this was the incipient (beginning) stage and therefore the use elevator to stop the stall and the rolling tendency was correct?

BruceAir
11-25-2012, 07:42 PM
Thanks for the clarification. At :56 sec. in the video (2:53 remaining) you describe the recovery from the incipient spin by stopping the stall first ("as soon as we stop the stall the rotation stops") with elevator - That was the source of my confusion. Am i correct that when you were inverted and beginning to roll this was the incipient (beginning) stage and therefore the use elevator to stop the stall and the rolling tendency was correct?

In these videos, I deliberately allowed the stall to progress to show the effects of misapplied flight controls. If I had applied down-elevator immediately at the first sign of a stall, the departures wouldn't be apparent. You can't go wrong following the PARE sequence whenever the airplane departs and begins an incipient spin, but if you stop the stall immediately, you regain control of the airplane and can stop a spin from developing. That's the key takeaway from these videos. At the first sign of stall or impending departure, unload (relax back pressure and/or apply forward yoke/stick) to keep the stall from progressing. As I noted earlier, the first instinct of many (most) pilots when a wing drops during a stall is to apply aileron to try to stop the roll, and that action delays recovery and tends to aggravate the stall. In the initial stages of a stall/departure, push first; correct the roll later.

As the Airplane Flying Handbook notes (see "Fundamentals of Stall Recovery" in Chapter 4 on p. 4-4):


First, at the indication of a stall, the pitch attitude and angle of attack must be decreased positively and immediately. Since the basic cause of a stall is always an excessive angle of attack, the cause must first be eliminated by releasing the back-elevator pressure that was necessary to attain that angle of attack or by moving the elevator control forward. This lowers the nose and returns the wing to an effective angle of attack. The amount of elevator control pressure or movement used depends on the design of the airplane, the severity of the stall, and the proximity of the ground. In some airplanes, a moderate movement of the elevator control—perhaps slightly forward of neutral—is enough, while in others a forcible push to the full forward position may be required. An excessive negative load on the wings caused by excessive forward movement of the elevator may impede, rather than hasten, the stall recovery. The object is to reduce the angle of attack but only enough to allow the wing to regain lift.

It's important to understand how a stall develops into a departure, incipient spin, and then developed spin. You can, for example, see the difference between the type of stall/departure/incipient spin that occurs when you stall out of a yawing turn, and what you see during a deliberate spin from slow-deceleration, wings-level stall. This is why competent stall/spin/upset recovery training is valuable. You need to experience and practice a variety of situations.

Stinson Pilot
12-07-2012, 05:47 PM
Very good!
I'm in Fall City and some time next year plan on taking your spin course.

Thanks again...

1600vw
12-07-2012, 07:04 PM
Bruce yes thanks for sharing this video.

Slips when coming in to land. What should one watch out for when one slips on final. When I did it I was a little higher then normal and kept my speed up by attitude of plane not throttle.

My Pitot tube was on my left wing, I was slipping to the left, was this correct or does it matter? I did not trust my ASI when I was doing this so I was flying by feel or the seat of my pants.

On the next landing I kept her straight with rudder input and kept the wing in the wind down.

I think the slip was more fun or more enjoyable.

What kind of G forces are you seeing in the moves you did?

I did a Hamerhead once in my little bird a Fisher Avenger that tips the scales around 450lbs dry, it was a lot of fun but not sure what loads I was putting on her so I will not do it again. But I see how arobatics can be addicting. I was smiling from ear to ear. It was great.

Lets see more....Thanks again for sharing

BruceAir
12-11-2012, 03:02 PM
Slips are normal maneuvers. You fly a slip at some point every time you do a crosswind landing. The airspeed errors that occur in slips usually result more from disruption of air around the static ports, not the alignment of pitot tube.

Slips, stalls, and spins don't impose high G-loads on the aircraft. G usually become a factor only during the recovery.

If you have questions about slips, see "Intentional Slips" in Chapter 8 of the Airplane Flying Handbook (http://www.faa.gov/library/manuals/aircraft/airplane_handbook/) and fly with an instructor.

(http://www.faa.gov/library/manuals/aircraft/airplane_handbook/)