Practicing stall recovery, the fabled base to final turn with engine failure

[paul330]

I've had this discussion before in these forums and pretty much got flamed. However, I'll give it another go. I wouldn't attempt a turn back unless I had at least 1000' under my belt or turned crosswind. Bear in mind I have 18,000+ hours including military fast jet and instructor. Here's why -

- you are going to be surprised. It will take longer than you think to get the nose down so you are probably going to be slower than you plan

- to do the maneuver effectively, you need 45 bank

- you are going to have a lot of adverse yaw, especially if you pull and load up. This will swing the nose up and further reduce speed

- "I've practiced it dozens of times". At altitude, if you have any sense. Chances are you are going to have a lot of ground rush that you didn't anticipate. So again, instinctively pull up a bit

- now you realize you aren't turning as you want so put in bottom rudder to help the turn. The video shows the rest. 800' minimum to recover when you were ready for it. Basically, you are dead.

Now I'm going to hear about the mountains, trees, alligator infested lakes ahead so you have to do it. Fine. Assess your own risks. But in general by far the safest option is to land ahead - usually. A turn back may save the aircraft if you get it right but everyone should understand it is a high risk maneuver. Landing ahead may end up with a bent aeroplane but chances are you will walk away from it.

My 2c (or 2p ....)

[Low Pass]

Originally Posted by paul330

I've had this discussion before in these forums and pretty much got flamed. However, I'll give it another go. I wouldn't attempt a turn back unless I had at least 1000' under my belt or turned crosswind. Bear in mind I have 18,000+ hours including military fast jet and instructor. Here's why -

- you are going to be surprised. It will take longer than you think to get the nose down so you are probably going to be slower than you plan

- to do the maneuver effectively, you need 45 bank

- you are going to have a lot of adverse yaw, especially if you pull and load up. This will swing the nose up and further reduce speed

- "I've practiced it dozens of times". At altitude, if you have any sense. Chances are you are going to have a lot of ground rush that you didn't anticipate. So again, instinctively pull up a bit

- now you realize you aren't turning as you want so put in bottom rudder to help the turn. The video shows the rest. 800' minimum to recover when you were ready for it. Basically, you are dead.

Now I'm going to hear about the mountains, trees, alligator infested lakes ahead so you have to do it. Fine. Assess your own risks. But in general by far the safest option is to land ahead - usually. A turn back may save the aircraft if you get it right but everyone should understand it is a high risk maneuver. Landing ahead may end up with a bent aeroplane but chances are you will walk away from it.

My 2c (or 2p ....)

Your points are well taken. But, the one factor that exists with every instance of engine out on takeoff/turnback/engine out landing scenario is - every pilot, (E-AB) plane, specific loading (weight, passengers, CG), surrounding terrain, and weather condition will all be different. One size does not fit all. It may fit many, but not all.

[Doug]

Eddie,
Excellent video, very good demonstration and I'm pretty sure this is a major killer in most categories not just RVs. Thanks for documenting it so well. I need to go through this myself with an instructor.

BTW you said during the vid that Best Glide is 80kts. Is that best endurance (ie lowest decent rate) or best range?

[paul330]

Originally Posted by Low Pass

Your points are well taken. But, the one factor that exists with every instance of engine out on takeoff/turnback/engine out landing scenario is - every pilot, (E-AB) plane, specific loading (weight, passengers, CG), surrounding terrain, and weather condition will all be different. One size does not fit all. It may fit many, but not all.

I believe I acknowledged that, Mark.

However, it's all about risk/reward. To land ahead is relatively simple. The chances of not damaging the aircraft, unfortunately, are low. But even if you flop in at 50kts, the chances of survival are good.

Turning back is an extreme maneuver requiring high levels of skill. It is unforgiving. I taught in training jets in the RAF. We had strict limits in respect of height and speed to attempt such a maneuver. Only instructors were allowed to attempt it. If it went wrong, we had an ejection seat. Students were not allowed to attempt it and we were forbidden from demonstrating it to them. This in an aircraft that gained energy quickly with (forgive me) above averagely skilled pilots.

The bottom line is that to pull it off successfully is extremely difficult. The consequences of failure are nearly always fatal. Watch the video again.....

[eddieseve]

Originally Posted by scottperthrv7a

Hi Eddie,

Did you get a chance to add this to Youtube? I'd like to share with some people not on facebook.

Regards,
Scott

Hi Scott

YouTube version as requested

https://youtu.be/RJCMbzKt5Yk

Cheers

[rockwoodrv9]

Thanks for putting it on youtube. I have told several friends to watch this video. There may be better videos about the stall spin, but this is the best I have seen to explain how so many both low and high time pilots can get into trouble very quick.
Buy your instructor lunch. He deserves it!

[paul330]

Here's why, in a nutshell......

- At 60 AOB, you pull 2g in a balanced turn

- Stall speed is proportional to SQRT of g = x1.414

- So, if Vs is 50kts, it is now 70kts. Assume your best glide is 80kts - see where this is going? Your margins have gone.

- Put in bottom rudder. The lower wing goes back, reducing its relative airspeed. Also, a certain amount of blanking from the fuselage. Lower wing stalls and you tuck under.

- Back to the video........

If you really feel the need to turn back after an engine failure then firstly keep some extra speed. Secondly, at the first sign of any loss of control unload the wings and roll level to the nearest horizon. if you have to land ahead, so be it. Flop in at 50kts and you have a good chance of walking away......

[eddieseve]

Originally Posted by Doug

Eddie,
Excellent video, very good demonstration and I'm pretty sure this is a major killer in most categories not just RVs. Thanks for documenting it so well. I need to go through this myself with an instructor.

BTW you said during the vid that Best Glide is 80kts. Is that best endurance (ie lowest decent rate) or best range?

Hi Doug

From my testing it was best range.

Cheers
Eddie

[paul330]

Without wishing to monopolize this or in anyway sound condescending......

Best glide of 80kts is wings level. In a turn, you increase induced drag so the total drag curve moves up and to the right, hence best glide (the tangent from the origin - best EAS/drag ratio) increases. Worst case (dependent on lots of variables) if you maintain the normal best glide, you could be below min drag speed and therefore speed unstable.

So, there are 2 good reasons to have extra speed in a turn engine out.......

[MikeyDale]

Reason to start the turn with extra speed, most days here in West Texas in the spring the wind is close to 20kts. Imagine starting the turn with +20 and ending the turn with -20!