One of the absolute best explanations I’ve ever seen about the skidded turn stall that kills so many. And Otter also very clearly demonstrates that by pushing harder on the rudder to try to tighten the turn and make your final to base, doesn’t actually tighten it at all.
That’s very good. Thanks for sharing.
It’s a very good explanation and unfortunately your average instructor would not have sufficient understanding themselves to be able to explain this to a student pilot. Why is video training like this not a mandatory part of PPL training? Why rely on an instructor to explain something when the explanation can be captured on video and fully standardised.
Does this scenario really “kill so many people” though? Is there data to back this up?
Is there any consensus here on EGA that the energy management turn, aka crop-duster or ground attack turn, should be learnt well before first solo – unless the only objective of flying schools is to produce airline pilots?
The alternative, constant pitch attitude level turn must be learnt at some later time for instrument flying, but shouldn’t that come after the student has mastered the art of contact or ground reference flight?
Both of the skidding and slipping turn stalls are not well understood. How many students understand that a slipping turn stall will put you on your back on the outboard side? I certainly did not get any ground or air training talking about this when I did my Swedish, UK and US licenses. Had to discover the explanations myself. Now, there was always talk about flying coordinated, but there was very little talk about why you need to do so. This clip is a great example of that.
That’s one of many methods to explain it, but I prefer the more simple one, because it is easier to understand than all that “swept wing” stuff in the video. It use has some interesting aspects, but the beginner will not understand it.
The airplane overbanks because of too much inside rudder and when the pilot tries to raise the falling wing by opposite aileron that part of the wing can easily go beyond the critical AOA because of the downward deflection of the aileron, combined with the accelerating outside wing and the pilot trying to raise the nose again by pulling.
All this can be prevented if you follow the basic rules: no banks greater than 20 degrees to the ground, do not corsscontrol and do not pull if there’s a cross controlled condition, yaw. Yaw+Stall=Spin.
ortac wrote:
It’s a very good explanation and unfortunately your average instructor would not have sufficient understanding themselves to be able to explain this to a student pilot
I somehow find it hard to believe that this kills many people. Flying coordinated is something instructors always keep nagging about. The only exception in normal flight is sideslipping (necessary in old Cubs).
Adam what a great find, thank you for posting. Very nicely explained. A companion piece would be showing how side slip may provoke a departure towards the up wing, but is easier to recover from.
Low level stall/spin is still an intractable fatal accident cause, despite the two hours minimum flying training in stalls, and threat and error management in the circuit. Ensuring pilots line up in a co ordinated manner with the centreline still seems to be a challenge. I believe loss of control VMC is still up at around 40% in the US as an accident scenario, and over 50% in the UK. (This would be VMC accidents). The CAA may have a poster campaign going at the moment as the trend seems to be getting worse.
I liked his explanation that on skidding your inside wing adopts stall characteristics of a swept wing. Trying to correct the second effect of yaw with aileron reduces the critical angle on the wing with the down going aileron, does not increase the angle of attack. It is the rolling motion from increased lift on the up wing which increases the angle of attack on the downward rolling wing. The combination of the two, plus some acceleration in pitch causes the low level flick roll. Technically not a spin as the up wing is still flying and is not stalled.
The Piper taper wing design has pronounced wash out and stall strips to make the wing spin resistant, and have good manners in the stall (trailing to leading edge, and root to tip). Combined with a limited range stabilator the PA28 taper wing has a significant safety advantage. Checking the NTSB no Warrior has had a stall/spin loss of control accident, although some Dakotas and Arrows have come down with ice contamination.
Bill Crawford at flightlab.net and Alan Cassidy in Better Aerobatics have very good articles or chapters on spinning. Brian Lansburgh has some good insights on side slips and skidding turns at tailwheelersjournal.com
I never understood why this is such an issue. In basic training you are taught that you turn by banking the aircraft, right? The rudder is used only for keeping the ball in the middle (except in a deliberate slideslip, like in a wing-down crosswind landing). So where does the idea come from that you can increase the rate of turn by using more rudder with a constant bank angle?
To be honest: I was never taught anything beyond “push the stick sideways to turn as you wish, use feet to keep the ball centred”.
Looks like some advanced training could be useful.
