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Old 16th Sep 2011, 04:42   #41 (permalink)
 
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LeadSled,

Not in my neck of the woods. In fact, it was a CASA FOI who changed my technique from throttle to mixture.

But I guess there lies the problem. No consistency from them, some strange ideas about how things should be done, yet they expect instructors to know the square root of the pickle. One of the major reasons I had to get out of instructing.

Lead, regarding your last comment asking whether the pilot did a good job, not sure if that was aimed at me or someone else. I wouldn't have a clue about that particular case, but I wanted to join in the debate about multi training. There was some strange stuff being posted, which needed balance in case any new or aspiring meta instructors were reading.
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Old 16th Sep 2011, 05:50   #42 (permalink)
 
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May I put another foot in the water and ask what's the current acceptance and/or procedure for single engine approach and landings in a conventional twin? It was done in my day, I have no idea now.
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Old 16th Sep 2011, 07:52   #43 (permalink)
 
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I do. At the very least one full feather-shutdown-secure-and-landing in an endorsement, and preferably two or three. Also at least one gear failure and manual extention. And any other emergency that I can safely demonstrate in the aircraft.
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Old 16th Sep 2011, 10:29   #44 (permalink)
 
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If CASA want you to shutdown and feather the prop to simulate the failure, they're going against their own documentation. From the CAAP, feathering not recommended:

Quote:

Propellers should never be feathered in flight during training below 3000 ft above ground level (AGL).
Quote:

Finally, CASA strongly recommends that, when practicing asymmetric flight, an aircraft should never be landed with the propeller of a serviceable engine feathered. The risk far outweighs the minimal benefits, with abundant examples of such unnecessary risks proving fatal. If a landing with a feathered propeller on a serviceable engine is contemplated, a
comprehensive risk assessment should be made and a clear plan developed. The plan should include weather, traffic air traffic control and any other factors
But nothing says you can't use the mixture to simulate the failure. It only talks about the throttle being kinder to the engine, which has previously been proven incorrect.
Quote:

5.5.2 Instructors must emphasise that during a practice
engine failure, when the throttle is closed and the propeller is
windmilling this replicates the situation of high propeller
drag that exists until the propeller is ‘simulated feathered’,
when zero thrust is set. Slowly closing the throttle is
probably one of the methods used to simulate an engine
failure. Although selecting idle cut-off may be kinder to an
engine, the engine or aircraft manufacturer may not permit
it, so slowly closing the throttle to idle or zero thrust is
unlikely to harm the engine and allows for immediate
restoration of power. When setting zero thrust (only after the
student has completed the simulated feathering), throttle
movements should not be rapid, and of course the student
Quote:

should have been briefed about your actions.
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Old 16th Sep 2011, 10:41   #45 (permalink)
 
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Quote:
But nothing says you can't use the mixture to simulate the failure. It only talks about the throttle being kinder to the engine, which has previously been proven incorrect.
FTS ..... proven?
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Old 16th Sep 2011, 11:09   #46 (permalink)
 
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Proven, documented and published by Lycoming. For some mysterious reason I find them a more authoritative source than CASA when it comes to matters of engine handling.

Quote:
If a landing with a feathered propeller on a serviceable engine is contemplated, a comprehensive risk assessment should be made and a clear plan developed.
As if a competent instructor would do it any other way.

Last edited by Unhinged; 16th Sep 2011 at 11:34.
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Old 16th Sep 2011, 12:44   #47 (permalink)
 
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Who's just talking about pistons? Turboprops fit in the lightie category for certification ie FAR23. I flew a Cheyenne 1 the other day. PT6s can have a failure that causes a massive power increase on the affected engine. In that instance, 'dead foot, dead engine' is also likely to be 'dead pilot'.

Anyway, a failed engine isn't necessarily the clean stop, black & white process that tends to be what happens in training. A surging, rough running piston engine also needs gauges to be checked. Not just for the suspected problem, but also to find the *good* engine . Random (or semi-random) yawing back & forth isn't really amenable to a simple 'dead foot, dead engine' philosophy. You can find yourself dancing on the rudder pedals to hold a heading.

As for confirming what you already 'know': Better would be '...what you *suspect*'. Lots of accidents where the pilot made the information available fit his or her preconception. It's important to look for contradictory evidence too.
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Old 16th Sep 2011, 12:50   #48 (permalink)
 
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Around, around, around she goes...and where she stops....??
Well old Macca can go on risking his and his students necks for all his worth.
Me???..past it now, dont like sitting there sucking up leather these days..besides I sort of want to enjoy the grandkids.
Used to be a real "Gun" in my early instructor days..leave my students white faced gibbering wrecks!!...until enlightenment, and getting the crap frightened out of me, then I realised a rational "Safer" approach achieved the same result..which is "Competence"...can take a little longer...but a hell of a lot safer, you just have to build a scenario and make it believable, with lots of air between your ass and the rocks...and to hell with the "regulator"..one of whom thinks a microsoft bench top simulator will give a student a realistic demonstration of assymetric performance.
No browney points for killing your student guys.
Oh!..and for those that subscibe to full feathered approaches..Technically with an engine shutdown and feathered you are in an emergency situation.
Until such time that the engine is restarted and the prop unfeathered.
Do you declare an emergency when you feather one?

Last edited by thorn bird; 16th Sep 2011 at 13:00.
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Old 16th Sep 2011, 14:40   #49 (permalink)
 
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Quote:
Who's just talking about pistons?
Everyone else. Your point about turbines is well made, but I never saw a mixture control in the cockpit of a turbine aircraft, and that's been the guts of much of the discussion. Sorry, I have no idea about FAR23, or what it might mean to this thread.

Quote:
Technically with an engine shutdown and feathered you are in an emergency situation.
Are you saying that as personal opinion or regulatory requirement ? In either case I don't agree with you, and nor does CAO 20.6 or anything else in the Regs that I know of.
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Old 16th Sep 2011, 15:43   #50 (permalink)
 
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Quote:
Quote:
Technically with an engine shutdown and feathered you are in an emergency situation.
Are you saying that as personal opinion or regulatory requirement ? In either case I don't agree with you, and nor does CAO 20.6 or anything else in the Regs that I know of.
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In light twins with their characteristic lack of single engine performance, landing with a prop feathered - whether a practice or due to engine failure - is worthy of a PAN call to alert ATC. In any case, deliberately feathering a prop for a "practice" single engine landing is bordering on reckless behaviour by the instructor since there is no regulatory requirement to do so. The handling of the aircraft with prop feathered or with the `dead` engine set at zero thrust is practically identical. Zero thrust landings are clearly good risk mitigation - while the former is high risk if numerous relevant accident reports are anything to go by.
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Old 16th Sep 2011, 20:52   #51 (permalink)
 
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Engine failures in turboprops are slightly different. Yes, an increase in power can occur. However, the engine instruments provide much more insight as to what is going on, when compared to a twin piston.

Verifying the failed, or failing, engine usually involves checking the engine instruments rather than using a power lever through its range.
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Old 16th Sep 2011, 21:20   #52 (permalink)
 
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Quote:
The recommendation by the NTSB means that all simulated engine-out operation at the lower altitudes should be accomplished by carefully retarding the throttle and this should be done slowly and carefully to avoid engine damage or failure. This careful technique will protect the engine and at the same time provide for instant power if it is needed.
Just goes to show that even highly competent, highly respected professionals can fall into the trap of suggesting that one method will always be less risky than another.
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Old 16th Sep 2011, 21:48   #53 (permalink)
 
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Quote:
Proven, documented and published by Lycoming. For some mysterious reason I find them a more authoritative source than CASA when it comes to matters of engine handling.
Or mis-handling more correctly, however the debate is not about whether the engine gets damaged or not, it as I understand, about the safety of the aircrew during the drill.
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Old 16th Sep 2011, 22:49   #54 (permalink)
 
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Mis-handling was not the result of what method of 'simulated engine failure' was used. I highly doubt there is any link at all between mixture cuts and loss of control in asymmetric training.

In every light twin trainer I flew instant power was available once the mixture was restored to rich.

Not that instant power is going to do a lot once control has been lost. Increasing power is not a Vmc-loss of control recovery technique.
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Old 17th Sep 2011, 00:17   #55 (permalink)
 
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VH-FTS

as I understand and was taught, the ONLY way to identify a problem engine in a turbo prop is by "TORQUE, TEMP, and FUEL FLOW". In the case of an overspeed governor failure, sometimes you might need to take your feet off the rudder pedals (but not too far) and see where the ball goes. Sometimes a bit hard to read a couple of percent on the on the gauge.
To repeat earlier, dead foot - dead engine in a turbo prop can very quickly lead to a dead pilot.
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Old 17th Sep 2011, 00:19   #56 (permalink)
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One observation I don't think has been noted in the thread -

For an OEI feathered landing on an aeroplane with big wind wallopers there is a significant yaw due drag on the operating engine(s) which won't be seen with a zero thrust situation as all engines go symmetrically to idle at the flare. I've only seen this on the L188 (4 x 4000 HP as I recall) and it certainly gets the pilot's attention if he/she is half asleep.

I don't really think that this problem necessarily warrants real OEI landing practice and, in general, such aircraft usually will have access to simulator training. However, folk should be aware of the problem so that they don't get caught out when the throttles are closed.

Can't say that I've ever noticed any yaw on lighties, though.
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Old 17th Sep 2011, 00:41   #57 (permalink)
 
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John, good point.

The yaw I experienced during a feathered landing with the chief pilot was noticeable, even in a light twin. The biggest thing is the lack of drag - when selected to idle power the windmilling prop would normally be creating a large amount of drag.

The 'opposite' yaw during the flare wasn't huge, but a float could be experienced. I would pre-flight brief the student that during the landing they could reduce power on 'their' engine only - the good one. I had control of the 'dead' engine. I would ensure a small amount of thrust was being generated by the dead engine to simulated feathering.

It was also briefed that if the approach or landing turned to crap, both engines were available to the student. Since the mixture had been returned to rich when setting zero thrust, a go- around setting could quickly be achieved on both engines.

Back to the feathered landing, a review of the ops manual showed intentional feather approaches were not permitted. I wasn't impressed the chief had failed to know this, but to be honest I should have picked it up as well. With all of the risk and stress involved in conducting this sort of approach (for ATC as well) I wasn't keen to do it again.
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Old 17th Sep 2011, 04:55   #58 (permalink)
 
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CAAP 5.23-1 (1) is a great publication. All M/E Instructors should read this thoroughly and then read it twice more. The biggest problem I think is ineperience and complacency. Gee I always demonstrated and observed full feathered landings. Remember you ,the instructor, knows this (the m/e trainer) aircraft like the back of your hand. Yep, sure many times there were "goof" ups but nothing you wern't expecting nor could get out of.
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Old 17th Sep 2011, 14:47   #59 (permalink)
 
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Folks,
I would have thought (how naive of me) that the number of fatalities we have on record during EFATO training, alone, would be enough to illustrate we have a serious problem.

A quick and dirty analysis says we kill more students and instructors in dual twin training than dual single training ??

Obviously, many of you on this thread still haven't joined the dots ??

As to the most recent accident at Camden, read the ATSB report, and then decide whose description of events was the more credible.

The ATSB leaves that up to you!

Although (curiously) not mentioned in the report, eye witnesses reported that the Twin Comanche's right engine was feathered, and in the pics in the report this seems to be so ----- was this smart ??

Was this training flight in conformity with the CAAP?? - NO

Was this flight in conformity with the "informal compliance instructions" of CASA YSBK?? - YES

Was this a great display of airmanship and CBS (aka common bloody sense) - What do you think??

The pilot (instructor) must be the greatest pilot since Pontius, from 400', stalled, rolled through 120 degrees, spun, recovered vertical nose down and recovered (with full tips) to wings level and almost "normal" attitude --- all in 400', in a Twin Comanche ---- or anything else, for that matter??

It's only a short report (sadly), make up your own mind.

Isn't it about time we stopped killing people "practicing" maneuvers for which the aircraft is not certified --- and often contrary to the AFM -- AFM compliance which is required by law --- despite anything said to the contrary by CASA FOIs.

Tootle pip!!

PS 1: -FTS, no, I wasn't referring/alluding to you ------ but please ignore the "recommendation" of a ratbag FOI ---- and just do as the NTSB/FAA says, anything more is a lousy risk/reward equation --- but rational risk management has never been Australian aviation's strong point ----- as born out by the record, there for all to see.

PS 2: Another ripper from CASA YSBK was "demanding" that the stall/attitude warning and stick pusher on Metro III/23 be disabled and the aircraft pulled into a full stall, to "comply with the CAO". It took a very strongly worded letter from the aircraft manufacturer to pull the plug on this suicidal nonsense.

PS 3: I worked for an airline whose rules suited me just fine --- shutting down an engine (except in a genuine emergency --- and before you ask, this was before simulators better than the Link IV ), was prohibited below 3000', and then only in daylight, VMC. Given said airline's reputation for training excellence and safe operation, is there a message here?? ---- all their aircraft ARE certified to continue after an EFATO at V1 or after.

PS 4: Craig Butson's ( Polar Air) troubles all started after a refusal to operate to the instructions of an FOI --- instructions that were contrary to the CAAP and all the other CASA recommendations about precautions to be taken during any asymmetric training.
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Old 18th Sep 2011, 06:28   #60 (permalink)
 
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Quote:
Gee I always demonstrated and observed full feathered landings. Remember you ,the instructor, knows this (the m/e trainer) aircraft like the back of your hand. Yep, sure many times there were "goof" ups but nothing you wern't expecting nor could get out of.
After the war many newly graduated RAAF pilots who had only ever flown Tiger Moths and Wirraways, were given their initial multi engine training on the four-engine Lincoln bomber at Amberley, Townsville and some at East Sale. Keep in mind this big bomber was a wartime tailwheel design. The conversion course included practice feathered prop landings and go-arounds.

Several of these aircraft crashed (two at Townsville alone) during asymmetric training with prop feathered. The flying instructors of these aircraft were highly experienced pilots yet they stuffed up. RAAF HQ realised they were losing more Lincolns to practice feathered landings than in day to day normal operations and directed that in future practice feathered landings were prohibited. Zero thrust approach and landings were substituted instead. The same applied to all RAAF multi-engined prop aircraft. The accident rate went to zero.

Draw your own conclusions.
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