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View Full Version : Feather or Simulated Feather: what's the usual?


Oktas8
5th Oct 2013, 13:03
Recently an experienced pilot told me that he flies practice instrument approaches (flying school stuff) with a fully shut down engine, for MECIR training.

An alternative is obviously to do the training with a simulated feather scenario.

I'm wondering which is more common, or whether both are regarded as common practice. I would have thought that doing full shutdowns was quite rare these days, once or twice in each student's flying school experience. Is that not so?

Now there are many threads of anti-mixture-cut rants, pro-mixture-cut hobby horses, CASA-requires-shutdowns speeches, etc. This isn't the place for that, please.

Nomde plume
5th Oct 2013, 13:25
Requires a lot of trust in the unfeathering accumulator, or a lot of airspeed to get going with the starter. Would guess most piston twins used for training wouldn't meet required missed approach gradients and approaches like YMEN ils explicitly forbid it. I think students need to actually feather props a few times in different configurations (climb, descent, turns, approach, etc), to actually see the difference a feathered prop makes, but at a safe height (2-3k) with visual reference without the stress of IFR training. Engine failures in IMC can be practiced in the sim with feathering. After initial multi training and if the student is comfortable with feathering a prop, zero-thrust is more than adequate for circuit and/or approach training. Lots of accident reports to go along with that I think!

Nomde plume
5th Oct 2013, 13:30
To answer your question, I don't know of anywhere where a full shutdown is 'common practice'. Maybe just shown once at some point towards the end of the training may be beneficial, but risky. Shock cooling of the engine also presents a major problem.

Timocracy
5th Oct 2013, 13:53
Full feather once to show the students what it looks like. Takes forever to get the engine back up to temperature.

Some schools do a landing with a shutdown engine to show the reverse yaw.(live engine creates more drag than a feathered engine when throttles are at idle)

Feathering the engine every time sounds like a hard life for the engine and an accident waiting to happen. Sure he didn't mean that he mixture cuts rather then simulating with throttle as some schools do?

waren9
5th Oct 2013, 14:04
i have never seen that as a student, nor have i done that as an instructor.

the benefits are outweighed by the risks in doing so, imho.

sure, feather it up high and unfeather for the exercise, but a 1eo approach for the sake of it?

even that reverse yaw thing? nah. if its on the ground surely the student will have the nouse to keep it straight.

edit. this raises a few questions for me. intentionally inducing a failure? is a pan call made? is atc notified that normal performance is not available should they require it? insurance validity in the event the running 1 stops? all sorts of implications...

Buttscratcher
5th Oct 2013, 14:55
Dumbest thing I've heard today

I mean, what's the benefit of shutting an engine down, only to fly a nicely trimmed aircraft down a 3 degree constant rate instrument descent profile?
Man, my grandma could do that.... Hell my dog could probably do that

Quick thought tho, I hope none of you guys have to risk your ass' flying the aircraft after this nut-job takes life outta those engines by shock-cooling those heads

Snapperhead!

Old Akro
5th Oct 2013, 22:20
I've done a full feather on each new a/c type and the CIR renewals are simulated.

The question is, why are you doing this? what is the training exercise?

I would suggest that you are trying to practice doing 3 things:
1. identify the dead engine
2. Go through the procedure of securing the engine & configuring the good engine to fly with.
3. Practice the transition to climb (ie go around) with the performance of a single engine.

As Buttscratcher suggests, there is little value in practicing the steady state condition. Its the transitions that require practice. There is also value in practicing this in the SIM because it keeps you fluent in the checklists & procedures.

Also, I rather like the idea of keeping the engine turning over, pumping oil, etc.

dubbleyew eight
5th Oct 2013, 23:54
from what I have been told Butson's troubles with the department arose from him not shutting the engine down during engine failure training.
his belief was that shock cooling would kill the engine. you can find the details of the ten year stouch with the department yourself.

a company favoured for their lead in training for commercial pilots here in perth has always shut the engine down in their duchess trainers. they have never had an engine die from shock cooling and in fact have taken each engine to its TBO, at last count one duchess was on I think its sixth set of engines.

there was a double fatality near perth not so long ago of two guys flying home in their reasonably newly acquired twin.
they lost an engine and it is believed that they applied the corrections to the wrong engine. it is possible that they had never experienced an actual dead engine before. both are dead so they can't tell us.

draw your own conclusions gentlemen.

VH-FTS
6th Oct 2013, 00:54
Sounds like a good way to kill yourself and a student pilot who doesn't really know any better.

While it isn't 'law', CAAP 5.23-1 about multi engine training states (para 4.17.9) :


"Propellers should never be feathered in flight during training below 3000ft
AGL"


You'd be a brave person to go against such recommendations. Previous flying schools and CAR217 organisations I have worked at stipulated something similar in their operations manual.

I'd say your 'fairly experienced' mate is either an idiot or has miscommunicated what "fully shut down" means. Closing the mixture doesn't mean fully shut down, but feathering the prop as well pretty much does.

Good luck getting it unfeathered when the (very likely) day comes that you need both engines. I've had many a unfeathering accumulator work poorly or not at all following a feathering exercise >3000ft.

Setting zero thrust is a MUCH more sensible option (and it doesn't matter if you cut the mixture or close the throttle as your failure technique). If you really want to demonstrate the 'reverse yaw' on touch down, don't close both throttles during the landing - leave that tiny bit of power on the 'failed' engine.

Slippery_Pete
6th Oct 2013, 01:38
Doing a shutdown and restart at higher altitude in VMC for an endorsement only (like most sane people), and flying approaches during IFR training with one shutdown and feathered are two completely different kettles of fish.

Why are we even discussing this?

Natural selection will eventually take care of this idiot, and we can all get back to CASA and ATSB bashing.

Oktas8
6th Oct 2013, 01:53
Thanks guys. I'm glad Australia was not late to class the day that airmanship was handed out!

Question answered, nothing more to be said.

Dashtrash
6th Oct 2013, 02:39
Many years ago as a multi instructor I used to do inflight shutdowns at altitude as part of the initial multi endo and I planned the exercise to be within a short distance of an airfield. Beneficial to actually see the feathered prop but more so for showing how to get it started again. (CAO20.6 used to refer to the availability of a shutdown engine for restart. Or some such wording) I did stack the cards in my favor. At a safe alt/airport nearby/100USG is not required for a 1 hour flight/ and 1 of 2 aircraft (Be76) that we used all the time and I knew the charge in the accumulators was good. I would do 1 and only 1 feathered landing as part of an initial multi but with similar personal minimums to mitigate some of the risks. With sound judgement, I believe these things can be done safely but there are limitations on man and machine that must be understood. Mixture cuts at night at low level are just stupid.

Centaurus
6th Oct 2013, 03:17
Recently an experienced pilot told me that he flies practice instrument approaches (flying school stuff) with a fully shut down engine, for MECIR training.

The RAAF learned the folly of that over 55 years ago after several crashes where propellers were feathered for practice asymmetric landings and engine failures after take off. There were two major crashes at Townsville three years apart but for the same reason. These were Lincoln four engine bombers where an outboard engine was cut and its prop feathered for landing.

In the first instance the instructor was an experienced former wartime Lancaster pilot who only nine years earlier had won a DFC when his Lancaster was hit by another Lancaster at night during a raid over Germany. Not only did he have part of one wing torn away, but lost two engines. He felt it was safer to continue to the target on two engines using almost full aileron and rudder (in IMC single pilot by the way) than do a 180 and risk a head on collision with one of a few hundred Lancasters of the incoming bomber stream.

But I digress. The point being he was an experienced multi-engine flying instructor and a good one too. I know, because I flew with him many times at Townsville. The pilot he was converting at Townsville was a experienced wartime pilot, so he was no sprog CPL in a Duchess. The instructor was demonstrating a feathered landing in the usual 10 knot cross wind on 02 at Townsville (the old wartime runway) and because of the poor visibility over the nose of the Long Nosed Lincoln (worse still at night), he found himself straddling the left edge of the runway during the hold off with No 1 feathered. He went around again but below VMCa.

By dint of full rudder and considerable aileron he was able to keep it clear of the ground but the aircraft continued in ground effect in a half circle around the aerodrome boundary until it hit a power pole. The Lincoln crashed and caught fire but the three man crew escaped with minor injuries. The Court of Inquiry blamed the accident on pilot error which of course it was. But in those days feathered practice asymmetric landings were the norm in training.

Then a few years later, another instructor was training new pilots (they had about 230 hours and the Lincoln was their first multi engine type). This was at Townsville, too. On final for 20 this time with the port outboard feathered for a practice asymmetric landing. The Lincoln bounced (and my, how a Lincoln could bounce...) and the instructor (by coincidence another wartime Lancaster veteran) took over and tried to cushion the bounce by applying power on the remaining three engines and letting the aircraft down gently. The asymmetric yaw got too much and he tried to go-around. VMCa all over again and the Lincoln crashed and burned. No casualties although it was close to the then civilian terminal. Pilot error once more was the verdict.

By now the RAAF brass had had enough and belatedly brought in an Air Force directive that practice asymmetric landings were to be confined to throttled back zero thrust only. Meanwhile in civilian flying feathered landings continued to this day with the loss of many aircraft and lives.

OK, so todays instructors on the Duchess and Seminole are not expected to know history of old accidents- but that doesn't preclude the use of good old fashioned airmanship and commonsense - or it shouldn't. But I sometimes wonder!

dubbleyew eight
6th Oct 2013, 05:29
mixture.

be careful of the image you create. I wouldnt want to fly with anyone I thought was a feral redneck. others probably feel the same. you never know.

LeadSled
6th Oct 2013, 07:51
his belief was that shock cooling would kill the engine

doubleyew8,
Quite simply no so --- Butson refused to do as demanded by an FOI, operate the aircraft outside its certified flight envelope as established in the AFM, per CAR 138. -- he wasn't concerned about the life of his engines, he was concerned about the life of his employees and himself.

Despite the CAAP mentioned in another post, we are still seeing pressure from some FOIs and equally dumb instructors/ATOs to "practice V1 cuts", something that does not exist in most FAR 23 certified aircraft.

As to the "training value" of shutting dowm engines completely (other than at a safe height, say min. 3000' AGL, daylight VMC) it is very clear that the "training value" does not exist --- compared to properly conducted zero thrust simulation of an engine failure.

The toll in dead bodies is there for all to see.

Jack Ranga
6th Oct 2013, 07:59
Isn't it a fact there are far more fatalities from multi engine training than there are from actual engine failures?

LeadSled
6th Oct 2013, 08:23
Jack,
A very short answer: YES!!

dubbleyew eight
6th Oct 2013, 10:21
well it looks like Butson got the last laugh.
if the stories are correct CASA had to pay out $10 million in compensation.

Centaurus
6th Oct 2013, 10:28
if the stories are correct CASA had to pay out $10 million in compensation.



I heard from a lawyer that compensation was also paid by CASA to the survivor (now safely back in Canada) of the Duchess accident at Camden several years back. That was the mixture cut shortly after lift off and the aircraft finished up skating along on its belly until it hit farm machinery and burst into flames. The ATO later died of burns.

dubbleyew eight
6th Oct 2013, 10:40
this drifts the tread a bit but there is a need for quality training.

of all the guys who learnt with me at Albury not one that I know of has ever pranged an aeroplane.
we were taught by ex point cook WW2 RAAF instructors in the main.
these guys weren't afraid to teach circuits in 25 knot crosswinds if they thought the student capable enough.
that is my background.

on our airfield over the last few years there has been a spate of minor accidents. all seem to have been taught by one instructor. I have heard one of his lessons when he keyed the mike accidentally and the delivery was immaculate. but his students keep on pranging aircraft so what gives?

what do you need to do to turn out a thoroughly competent pilot?
I suppose that is the $64 question, and the conundrum for CASA as well.

Kharon
6th Oct 2013, 22:22
I was, determinedly, going to stay out of this discussion; but rather than leave my two bob in my pocket:- Let's take three sprogs; Fred, Pete and Bill and do some multi engine training.

Fred has superb engine handling skills, reasonable stick and rudder but is slow on transition to instruments and getting from 'failure' to fix.

Pete has the book off pat, can quote the rules and checklist, but stick and rudder clumsy, doesn't 'get' the internal combustion engine, is prone to making quick decisions and rushing through checks.

Bill is OK generally, but when he reaches across the cockpit to reset #2 altimeter, the hand follows the eyes and thus the aircraft creeps 10° off heading and he is slow to correct it.

The list is as long as your arm, common or garden sprog basic issues. Now a good trainer should be able to identify and correct these by developing a hand crafted 'program' for either of the lads; develop their confidence and get them to a standard where OEI operations are basically an interesting, safe learning experience. Feathered or simulated? academic in a 'safe' – AFM supported environment, (FAR 23 certification - carefully considered) CAO 40 (IMO) being for the "guidance of wise men". etc.

But no amount of ticked boxes will correct the radical errors. One dark and stormy, when the number one is about to make a monkey of the engineers, is probably the only time in a career where all of the basic errors, not corrected will surface, this is not the time to start learning. How we get pilots to the stage of seamless transition and almost faultless execution under 'real' pressure is a matter of quality training and establishing sound 'default' settings. So that once in a lifetime event finishes in the bar, not at another cold wet gravesite.

Tick-a-box, black letter law, cover your arse, micro management cannot replace good, sound, 'intuitive' basic training. If the folk doing the training can't or don't recognise the errors, all the slavish dedication to tick-a-box training cannot and will not help. If the natural 'intuition' found within a good training pilot is beaten down by enforced, prescriptive legislation; how can we be certain that a box ticked is indeed, a job done well? At least later in life, a half decent check pilot will hone in on and target perceived weakness, this is as it should be; but is the candidate the problem or the training system??. Have a look about and see just who holds sway these days; it's most certainly not men of the calibre, intelligence and hard won experience Centaurus recollects.

Aye well, that's my two bob's worth; although I'll probably regret it later.... http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/wink2.gif

boofhead
8th Oct 2013, 19:03
In the mid 60s we would shut the engine down and feather the prop at 300 feet after takeoff in a twin Dart airplane for asy practice. Made lots of actual single engine landings and go arounds. We had the engine that was shut down ready for a relight. I had an actual engine failure at 500 feet once with the other engine shut down and got it running in time, but it was exciting for a while.

Had 5 engine problems requiring shut down in that airplane and the experience gained in training was invaluable. Made them non-events.

The policy was changed to only allowing simulated shut downs but not for any problem we might have had, just that it was felt to be safer.

I did appreciate the experience and think that I know a lot more about single engine flight because I had that opportunity. The point about the landing swing is a good one and there is no way to simulate that, even by leaving the failed engine at high idle. The yaw with an engine feathered is very dynamic.

I have had problems a couple of times with setting the wrong simulated power, in that the prop drag was worse than a feathered prop would have been and the airplane was on its way down, requiring quick action to save it. Usually turboprop engines that have a big prop drag, such as Garrets.

Twice have had a student roll almost inverted due to Vmca during training with the failed engine at idle, so I am familiar with the risks. My first twin was the DC3 and that airplane really teaches you a lot.

I shut an engine down in an Aztec for training and could not get it running again due to battery failure. Generator on good engine failed too, so we had no electrical power and sun went down before we could land. No radio etc luckily runway lights were already on. Of course the running engine did not have the hyd pump. It was a great learning experience for the student. Most pilots never have a chance to do this in their entire flying career.

You could not buy that experience. But in retrospect I think using the throttle to simulate an engine failure is best.

Centaurus
9th Oct 2013, 00:38
The point about the landing swing is a good one and there is no way to simulate that, even by leaving the failed engine at high idle. The yaw with an engine feathered is very dynamic.


Interesting observations. Personally I have not experienced the landing yaw on touch down in the many aircraft I have landed with a feathered prop in another era. . That includes piston and turboprop. If there was a yaw it was easily controllable and therefore negligible like a five knot crosswind weathercocking. On a light twin piston such as the Duchess/Seminole genre any yaw on a feathered touch down was a non-event and certainly not worth deliberately feathering a prop for just to experience a non-event. :ok: