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Old 17th May 2017, 15:13   #1 (permalink)
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PC 12 practice turn backs after simulated engine failure after take off

Part of the conversion syllabus of pilot training on the PC12 (RFDS and private operators) includes practice emergency turn-backs to the departure runway following a simulated engine failure after take-off. Is this a manufacturer's recommendation?
It could be argued this goes against everything that pilots are taught at flying schools when learning to fly because of the inherent risks of stalling in the turn at low speed and low altitude. When did that change?
The RAAF taught turn backs a long time ago, but changed that after several fatal accidents while practicing.

With the PC 12, what are the minimum required altitude and airspeed parameters (and max acceptable downwind component) before an engine failure turn back is contemplated?
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Old 17th May 2017, 16:30   #2 (permalink)
 
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A turn back can be a very nice option to have albeit a bit of an advanced one.
Few airplanes respond well to a panic induced yank and bank.
It takes a (relatively) cool head and understanding the dynamics to make it work.
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Old 17th May 2017, 17:29   #3 (permalink)
 
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Originally Posted by sheppey View Post
The RAAF taught turn backs a long time ago, but changed that after several fatal accidents while practicing.

With the PC 12, what are the minimum required altitude and airspeed parameters (and max acceptable downwind component) before an engine failure turn back is contemplated?
The RAAF still teaches them and practices them in the PC9. But I guess it's a little different because if it all goes horribly wrong the pilots can step out via the ejection seat.

There are strict gates that must be met and a turn back is limited to the QFIs.

As for manufacturers recommendations? I know Pilatus teach it at the factory for the PC7,9,12 and 21.
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Old 17th May 2017, 19:03   #4 (permalink)
 
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Your initial rate of climb has to be significantly greater than your gliding rate of descent to allow for the extra distance flown in the turn and realigning with the runway. No doubt Pilatus did the maths and worked out when it would work and when it would not.

I think I saw a video on youtube of a PC12 doing a turnback?
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Old 17th May 2017, 22:27   #5 (permalink)
 
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Can't comment on the PC 12 but in a 208 the issue generally is running off the end, not ending up short. So unless it's performed incorrectly it shouldn't be an issue. As to the decision to use it or not, that's a different kettle of fish.
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Old 17th May 2017, 22:49   #6 (permalink)
 
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It could be argued this goes against everything that pilots are taught at flying schools when learning to fly because of the inherent risks of stalling in the turn at low speed and low altitude. When did that change?
it could be argues that a lot of things taught at flying schools are "sub-optimal" because they were designed to cover ass for sub-optimal students. Or because that is what their instructor taught x 10 generations thereof.

As recently as this morning, John Deakin said to me
Quote:
"Really bugs me how so many people will very quickly adopt a bad practice and be so reluctant to even try a good practice."
There have been threads on this before, and my "take away" has been to simply KNOW YOUR AEROPLANE and know it well.

In my plane from 500-600 feet I am at risk of running off the far end and into the fence At 400-500 it is 45 deg turn, best glide, flap as required when sure of the field, and land, brake heavily. In the 300-400 range if light, no problem, if heavy, use the energy to find the best area to land as you will not easily make the runway, but you should make something flat enough on the field.

Could I do this in a 172, probably not, or an Archer, or even a PC12 (I know it will) so even if I know it will, I need to have trained for it.

That is why the RFDS and others teach it. If you can do it from 29,000 feet or 400' the rules are much the same, because the laws of physics do not alter much It is all about how you manage the event. How you prepare for every takeoff. Expect the failure and be pleasantly surprised when it doesn't.

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Old 18th May 2017, 01:08   #7 (permalink)
 
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A turn back is a manoeuvre, which if competently trained for, competently practiced and competently commenced from above a safe height, can be executed successfully.
To me, the training and practice is most important. And another good idea is a buffer in the minimum height practised (ie when you know you're going to practice one) vs your briefed height for normal ops - to allow for the "Oh sH$t" factor...
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Old 18th May 2017, 01:36   #8 (permalink)
 
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See:

https://www.youtube.com/watch?v=Q0IbtR0GwDE

and:

https://www.youtube.com/watch?v=s9vIZ_k8iYM
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Old 18th May 2017, 03:00   #9 (permalink)
 
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Sleepy,

I have a figure of 800' in my mind but it's been 14 years since I did one. If its not 800 it's close. It was a blanket not below height.

The PC12 is an amazing glider. It handles the turn back very smoothly and easily and safely. Unlike a PA28.
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Old 18th May 2017, 03:01   #10 (permalink)
 
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The RAAF taught turn backs a long time ago, but changed that after several fatal accidents while practicing
Any details what accidents and when the change sheppey? As far as I know it was still in use on the last Vampire course. Macchi at Nowra had a successful turn back in 1982 after the engine swallowed a bird whilst loaded with a passenger plus practice bombs and a minigun pod.

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Old 18th May 2017, 03:54   #11 (permalink)
 
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The PC-12 is essentially built around its wing which means it is possible to land on the same runway that you took off from above 750 feet right out to 75nm downrange. The old way to get it on the ground was pretty spectacular as well. Get to 5nm (from memory) point it straight down to Vne level out and do a perfectly normal circuit.

Excellent aircraft.
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Old 18th May 2017, 04:12   #12 (permalink)
 
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Ah yes, the 1:1 glide approach / cloud break. [email protected]', 6 at 6, 5 at 5 etc and level out at 700? feet and you can make any threshold. Even more fun (to practise) than the turn back
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Old 18th May 2017, 05:05   #13 (permalink)
 
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Essentially, the reason why turbine PC12 and similar aircraft do turn backs contrary to what is generally taught in flying schools is performance.

Most flying school aircraft are not capable of the kind of climb performance which makes the turn back manoeuvre achievable and safe in something like a PC12.

The other thing that makes a difference is currency. For example, RFDS pilots are practicing this regularly - generally every six months...
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Old 18th May 2017, 15:52   #14 (permalink)
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For example, RFDS pilots are practicing this regularly - generally every six months...
Commonly known as "practicing bleeding" like mixture cuts in light twins to simulate engine failures after take off.
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Old 18th May 2017, 17:41   #15 (permalink)
 
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So it seems you have a problem with the procedure in a PC12, without knowing how it's practised or flown. Nice work. The PC12 is no Vampire with which you are obviously familiar.

Last edited by compressor stall; 18th May 2017 at 18:14.
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Old 18th May 2017, 18:17   #16 (permalink)
 
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In 2002 I was on vectors for ILS6 at KTTN. I heard an Rwy24 departure check-in climbing to 2000. The PC12 pilot subsequently lost power, made a course reversal in IMC back to RWY6. At the time, I didn't realize this was a trained procedure. The synopsis can be found below.

here
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Old 19th May 2017, 01:00   #17 (permalink)
 
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Vampire with which you are obviously familiar
Would seem not CS. Shortly before he retired, the Governor General, Lord Casey, visited Pearce.

Previously, a young Navy student had been ordered to attend the CFI's office, and given the instruction that he was to present himself at XXXX hours on the following Saturday morning prepared to aviate. Student wondered what was up, as weekend work was never done, and he was the only one so ordered. Dire thoughts were at hand.

Turned out the G-G wanted to listen in on the "patter" used during a sortie. The arrangement made was for him to listen in on the tower frequency while the student and CFI conducted a session of turn backs, both to the cross runway and 180 in a Vampire.
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Old 19th May 2017, 01:43   #18 (permalink)
 
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G'day Megan,

My comment to Sheepy (who used to fly Vampires I understand) was that the turn back procedure in a PC12 is a lot simpler than that that pic you outlined above. No converting speed to height. The PC12 just glides amazingly well.

When we did my endorsement, out in the training area the checkie told me to pick a spot for a forced landing. I picked what I thought was the only likely spot -far from perfect but survivable - using my judgement of radius from piston singles. He asked why I didn't pick that nice big open salt pan way over there. "Um, because we won't make it..." was my reply. With a wry grin, he said yes we will, point her that way. We made it.

Last edited by compressor stall; 19th May 2017 at 02:37. Reason: Clarity
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Old 19th May 2017, 03:01   #19 (permalink)
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So it seems you have a problem with the procedure in a PC12, without knowing how it's practised or flown. Nice work
I am sure the PC12 and the PC9 are fine aircraft which glides very well providing the prop is promptly feathered. But what if for some reason the prop is inadvertently left windmilling? Do pilots practice for that eventuality? Of course we can play "what if's" until the cows come home." After all there have been several GA accidents over the years where a light twin has gone in after engine failure after take off and the pilot was so busy he never got around to feathering the dead engine prop. The C402 Aerial Ambulance fatal crash after taking off from Essendon 35 is a case in point.
But you are quite right - I have never had the pleasure of flying these turbo-props and unfortunately it is all too easy to be talking out of my arse which you alluded to with "Nice Work."
On the other hand I did have the unpleasant experience of being on the Court of Inquiry and thus seeing the awful aftermath of a Winjeel turn back after a practice engine failure that went wrong resulting in both pilots being burned to death on impact. That experience tends to concentrate your mind about the pros and cons of turn backs and whether or not practice makes perfect or even increases the chances of an accident based on the adage get away with something long enough and the perceived danger diminishes.

I guess if Pilatus and the RAAF are perfectly happy to teach the manoeuvre as a safe option to landing ahead its OK with this scribe.
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Old 19th May 2017, 03:17   #20 (permalink)
 
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The turn back discussion is a valid one and as there are many variables form aircraft design and performance to pilot experience. Trying to find a generalisation yes or no is going to get into heated discussion.

My throw away comment was aimed at the fact that you asked for the performance data presumably to make an informed decision and discussion, then throw that approach away with the prejudiced practising bleeding comment.
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