EFATO Light Twin/ Mixture Control.

[novicef]

After reading the thread on feathered landings and discussing multi-engine training with some of my colleagues. The general opinion is that asymmetric training is more realistic when engine failure is simulated by cutting the mixture even though there is a certain amount of risk attached.
Yet looking at the CAO’s, the requirements for a light twin to continue climbing away all be it at 1% climb gradient is only required AFTER the prop is feathered and gear and flap retracted. However It’s discussed quite openly EFATO is practiced just as the aircraft lifts off with both the gear and flap still extended and the method of simulating failure is by cutting the mixture.

There was an article in the Safety Digest published by CASA on multi-engine training that the preferred method of simulation was by closure of the throttle and setting zero thrust to simulate a feathered propeller. Yet the old method of EFATO simulation using the mixture control is still practiced even though it has caused several accidents. To add to this why does this exercise have to be conducted just after lift off when the gear and flap are still extended and the risks greatest. Even the performance requirements do not call for the aircraft to perform in that configuration. Perhaps a CASA Flight Ops Inspector would like to comment on this type of training.

[maui]

Novicef

It's a long time since I have been involved, so memory is a little hazy.

Conventional wisdom in the past was that a mixture cut was easier on the engine as the loading stays positive. If the throttle is pulled abruptly backloading occurs, which can do nasty things to dynamic balances. Additionally if the engine is of the geared variety the lay shafts take a caning.

The procedure called for the establishment of zero thrust when the candidate had correctly identified and simulated feathering. This would be done after the candidate has "confirmed" with throttle, and left the throttle on the back stop. Thus when the mixture is returned to full rich the loads are all the right way around.

Tell me how would you simulate confirmation after a throttle cut simulation? Perhaps you feel it is uneccessary to confirm. Short cut to an incorrect shutdown methinks.

Why is it done just as the aircraft breaks ground? Cos that's the most critical phase, and what needs to be experienced and practiced. If you have a failure at that point and don't do it correctly the ground WILL come up and smite thee, so why not practice it at training weights and with a professional at your side.

It is because of the criticality of the procedure that ME Training approval used to be hard to achieve. A situation that is no longer the case, if I understand the current state of play correctly.

This refers to initial piston twin endorsement only. Turbo props an entirely different matter, but by then the guy in the left seat should know the basics. Jets another kettle of fish and a whole lot easier still.

Maui

[Gear in transit]

Centaurus has a plethora of information/passion/rant on this subject, he will be the one to answer your question. :D

[brown_eyes]

I see your point on engine loads, however why would CASA suggest closing the throttle in the Safety Digest if it didn't adequately simulate an engine failure and the drills that followed, surely there has to be some merit in their suggestion.

[11percent]

two points,

firstly, the safety digest is full of one eyed opinions from others in industry looking to have their moment in the sun. It is a very long bow to suggest that becasues a particular point of view is presented, it represents all CASA FOI's. The only concensus here would be they all don't agree.

Second, most training providers that do M/E training that I have worked for use the mixture as it is kinder to the engines (loading as already stated). This becomes even more important when you introduce turbos and geared engines.

hope this helps.

[Centaurus]

Re mixture cuts.
so why not practice it at training weights and with a professional at your side.


I seem to recall the fatal Duchess accident at Camden a couple of years back that caused the death of the instructor and terrible burns to the student. The student had a "professional" at his side, too... And oh yes - it was a simulated engine failure caused by a mixture cut.

[AerocatS2A]

Hmmm, if someone were to "fail" an engine on me just on lift off, I'd be landing ahead as per my pre take-off brief (runway remaining or not.)

[7gcbc]

Re mixture cuts.
I seem to recall the fatal Duchess accident at Camden a couple of years back that caused the death of the instructor and terrible burns to the student. The student had a "professional" at his side, too... And oh yes - it was a simulated engine failure caused by a mixture cut.


That was horrific, some 40,000 hours between them too, what a shocking waste.

[MBA747]

Confirmation of an engine failure and identifying the correct engine is simple. For arguments sake if one was just sitting with their hands and feet off the controls the yaw itself would tell you which engine has failed. Yaw left left engine failed, yaw right right engine failed. Now assuming you have your hands and feet appropriately placed you can use the dead foot dead engine to further confirm which engine has failed. So confirmation is not a problem, in addition just because one pulls back the correct throttle lever, who is to say that you will not pull the wrong pitch or mixture control.

So the next point which I fear is more relevant, are we failing or simulating engine failure with mixture to reduce wear and tear to reduce costs thereby putting maintenance costs ahead of safety?

I was trained using the mixtures cut 30 years ago but then I was young and didn’t know better, fortunately now this is all done in a simulator. I am all for realism but not when safety is an issue. Perhaps if Multi Engine Training incorporated more use of the simulator where procedures could be honed it would be best for all. One thing I did notice at some of the flying schools was the availability of twin simulators which were not around in my GA days.

[Centaurus]

The Lycoming Flyer Key Reprints 1992 on page 49 has this brief (slightly edited for brevity) warning by the US NTSB.
"The fatal crash of a light twin in which a flight instructor was killed prompted the NTSB to issue an urgent warning to all pilots simulating an engine-out condition on multi-engine airplanes.
The Board's investigation revealed that some flight instructors do use the mixture control or fuel selector to shut down an engine to test a multi-engine applicant. Although this is a recommended procedure, the urgent warning was aimed at flight instructors who were using this procedure at altitudes too low for continued safe flight.
The NTSB observed that use of such procedures at traffic pattern altitudes may not permit instructors enough time to overcome possible errors on the part of the applicant. The recommendation by the NTSB means all simulated engine-out operation at lower altitudes should be accomplished by retarding the throttle and this should be done slowly and carefully to avoid engine damage or failure."

One presumes the term "lower altitudes" used by the NTSB covers simulated failures after lift off and below circuit height?

[Gear in transit]

I think a point that constantly gets missed on this topic is, what caused the accident? Did the aircraft concerned at Camden crash because the mixture was cut? Or was it because the aeroplane was too low, or got below Vmca? Would the accident still have happened if the throttle was used in leiu of the mixture?

It's fine to say 'mixture cuts are bad' but is that the real reason of the accident?

I think more of concern is what happens AFTER the failure has been simulated, ie airspeed, height terrain clearence ahead etc etc.

[MBA747]

The point being missed is that mishandling on each occasion has caused accidents. By using the mixture one does not have the option of restoring power to the other engine quickly, so why take the risk when you have other options.

One plans an alternate when the weather is bad, to have an option. However with a mixture cut followed by mishandling just after take-off the option is the coffin.

I wonder why airlines use simulators for this sort of exercise. It’s a pity CASA does not put an end to this stupidity

[rmcdonal]

How many seconds is it from Mixture cut-off back to full rich? How long does it take before the engine kicks back in? Serious question I don’t have META so have never had the opportunity to try it myself. In most cases the throttle is back to idle before the mixture goes rich, so what happens if you leave the throttle open?

[Chimbu chuckles]

In my experience of giving multi engine training using mixture cuts the engine starts immediately when the mixture is returned to rich...unless you have feathered the prop etc...which you generally don't do.

While the mixture was used to give the initial 'failure' as soon as the student had correctly identified the failure and carried out the memory items I would reinstate the mixture and set zero thrust on the now running engine.

The MOST important point of all is where you fail the engine not how. Any really experienced multi piston pilot uses 'gear up' as their decision point...i.e. if the engine fails before gear up I close both throttles and land straight ahead irrespective..after gear up it is memory items and fly if possible (and most DO despite the rhetoric). Of course it is a little situation specific and a decision will (should) have been made before commencing the takeoff based on knowledge of the aeroplane and the ambient conditions. A light twin at MTOW on a 40deg day will not fly on one so you would be predisposed to a controlled forced landing before even setting takeoff power.

That many multi instructors feel the need to fail engines right on lift off with the gear still down indicates ignorance and inexperience.

On the odd occasion when I have needed to climb into a piston twin with an unknown individual in the RHS I have made it ABUNDANTLY clear that if they fail an engine on me below 200' with the gear down I WILL land straight ahead with NO compunction whatsoever...If I bend metal it's their problem. Whether it was my tone of voice or the look in my eyes I am not sure but none have ever tried it on.

Morons have caused piston twins to have the reputation they have not the aircraft themselves. ANY piston twin flown correctly is 'safer' than a single. But that is the rub...since most piston twins passed from the hands of 3rd level airlines to small charter companies 15-20 years ago there has been a HUGE loss of corporate knowledge on how they should be flown.

The average CASA FOI is part of the problem not the solution.

[Bula]

Sorry guys for being so inprompt but lets put the the ballsand ego toone side for a second and think about this.
One thing which much be remembered is that we a simulating a failure and as a M/E instructorshould never cause an intentional failure. If your argument is so that they close the throttle WHO CARES???? REALLY? Is is so critical that they will remember on the once off? just look a sim check rides... how many pull the wrong fire handle under the pump?
Secondly, If you willing to risk your life that the student will handle the situation correctly... well good luck and I wish you all the best, but will you put you Life, friends and family behind that one?
Thirdly, As for reducing engine ware and tare..... I think its a whole load of brown stuff. You run an engine at 350 degrees and make it feel 22 degree air in the space of a few seconds..... now lets see who has the real failure (forgetting a geared engine).
Just some common safety tips fellas.. what you do is your own life

[Dashtrash]

It would be great if there was a full motion simulator for a Duchess/Seminole/Seneca etc but there just isn't.

In my few years doing ME Tng, I never ( and I think it was ops manual) failed engines below 300ft after take-off. I personally used the mixture control based on recomendations from Lycoming and info from the key reprints articles. Someone asked how quick? Immediately. Possibly even quicker that opening the throttle. How many touch and goes have started with cough-cough-cough stutter and then power.

In demonstrating the pitfalls of low level failures, think about how we demonstrate stalls. Why not set the aircraft up in t-o config climbing at the appropriate speed for type and then passing the pretend ground at 2000-3000ft agl, fail the engine. It might lack the bravado and adrenalin rush that some might love, but it works as a safe demonstration as to the performance or lack thereoff of light twims.

Lessons have to be learnt but think a little laterally and you'll be able to find safe ways to teach most areas. Think closely about the other things we do as instructors, single engine EFATO/solo PFL practice/ SE NVFR, is a PROPERLY managed exercise all that dangerous. Don't try this stuff at night as some have attempted.

And I'm spent

DT

[Centaurus]

Dash Trash.
You said: I never ( and I think it was ops manual) failed engines below 300ft after take-off. I personally used the mixture control based on recomendations from Lycoming and info from the key reprints articles

Well done. Now lets examine carefully exactly what Lycoming said in their magazine Key reprints as to the why's and wherefores of throttle versus mixture. Page 50 states among other things:
"Many flight instructors down through the years used the technique of abruptly cutting an engine with a multiengine candidate to test his emotional reaction (??is the instructor a qualified psychologist - I think not) and judgement with this extreme technique. Big radial piston engines with short stubby crankshafts could tolerate this abrupt (throttle) technique. However, flat opposed piston engines with their long crankshafts and attached counterweights could not as readily take the abuse of suddenly snapping a throttle shut, particularly at take off or climb power. Use of the latter technique would tend to detune crankshaft counterweights and could possibly result in a nasty engine failure.

Since it was common technique by flight instructors to terminate power abruptly to simulate engine power loss, we had to protect the engine. As a result we published in our Engine Operators Manual and in Service Bulletin No. 245, the recommendation that if the power was abruptly terminated it must be accomplished with the mixture control. Of course, this was intended for higher altitude where a complete engine shut down could be conducted safely. However, any practice of simulated engine-out condition at low altitude should be best accomplished by a slow retardation of the throttle in accordance with the NTSB recommendation."

So this suggests that the abrupt ripping back of a throttle was likely to cause engine problems. A slow throttle closure will not cause engine problems and has the added advantage of instant power available if mishandling occurs by either pilot. The mixture cuts were there to stop ham fisted instructors from stuffing the engines by abrupt throttle handling. That was the reason that Lycoming said mixture cuts were better for the engine.
As Lycoming said - "We had to protect the engines" (from ham fisted instructors)
And as for instructors testing the emotional reaction of candidates - surely that is a job for professional psychologists - not enthusiastic amateurs?

[Gear in transit]

Centaurus, I understand your passion of using throttle to simulate failures instead of the mixture, but can you perhaps answer what I asked in the post above? Has cutting the mixture directly caused an accident? As Chimbu said, usually once the student has called for feather, zero thrust was set, so I fail to see how cutting a mixture = accident. Perhaps handling AFTER the failure is the more prudent point.
When I DID conduct engine failures using mixture cuts, I had my own personal limits ie not <300' no rising terrain ahead (ie north rwy at Cobden etc) prior to doing that. However, this thought process didn't stop when I started using throttle cuts!! Point is, what difference does it make?
I am not trying to suggest that cutting mixtures willy nilly is a smart move, but nor is the throttle for an 'unsuspecting' student.

I also would like to see any data or evidence that advancing a throttle to full, versus a mixture to full is going to apply power any sooner.

[maui]

Centaurus

Granting of training approval and a delegation, transfers a reasonable amount of discretion. Provided the training covers the requirements and is conducted within broad parameters, all is well.

We all determine what is acceptable to us. If you determine that you require a lesser standard of demonstrated ability, than does a brother instructor/delegate, then that is a matter for your conscience.

I trust it will not come back to haunt you. I hope you never have that nagging feeling “could I have better prepared Blogs to look after the passengers he has just killed.”

Training is an inherently risky business. While I would never suggest that one should not try to reduce risk, there must be a point of balance. Obviously you have determined the balance you find acceptable. It is not mine.

No one here has suggested that we do multiple failures at critical points, however is it not reasonable to finish off with a couple at awkward times, to verify the integrity of the training and assessment.

You seem to have access to good resources. It would be interesting to research how many passengers have died from VMCA/stall/spin asymmetric accidents, as opposed to the number of instructors and Blogs lost in training. (Military excluded)

MBA747

You are confusing “identification” with “confirmation”

When using the mixture, you do have the ability to restore, and within a poofteenth of a second of the time it would take with throttle.

Chimbu Chuck

If you tried that sort of standover tactic with me I would be inclined to walk away and let you find someone else to do the test. That is not to say that I would do anything that might upset you, but you would have already demonstrated an attitude and inflexible mindset which in my assessment would disqualify you from the privileges of the rating. Fortunately for both of us I am no longer involved in that area.

LOL

Maui ;)

[AerocatS2A]

Maui, that's not a standover tactic, that is a take-off briefing. "In the event of an engine failure below 200', with the gear down, I will land ahead regardless of whether It is simulated or not."

[Chimbu chuckles]

If you tried that sort of standover tactic with me I would be inclined to walk away and let you find someone else to do the test. That is not to say that I would do anything that might upset you, but you would have already demonstrated an attitude and inflexible mindset which in my assessment would disqualify you from the privileges of the rating. Fortunately for both of us I am no longer involved in that area.

maui it was not a standover tactic but merely a setting of the maximum risk I was prepared to expose myself to in a training environment with a Instructor whom I did not know well or at all. If you weren't going to do anything dumb why would you be so upset? As to my suitability to excercise the priveledges of the rating?

I have > 3500 multi piston command, >3500 turbine command, 5000+ jet with 1500 odd command, have held every CASA C+T approval available for Corporate Jets + IFR initial/renewal approvals. C+Ting experience on Islanders, C402, C404, Aerostar, Queenair, Twin Otter and Falcons among others.

I would hate to think how many engines 'failures' I have given other people over the last 20 years or how many have been given to me. Everything from closing a thrust lever on a Falcon as the nosewheel left the ground (V1/Vr) with a young trainee FO on his first jet type rating (no sim available for the type) to failing pistons on the mixture at a few hundred AGL in PNG where we might be 5000 amsl in ISA+20 at a highland airfield or we might be over water just airborne from a coastal strip in an Islander, C402 or C404. Over the years I have done quite a few training full shut downs and feathered approaches and go arounds in things like Islanders because that was the company culture..including at places like Mt Hagen (5400' amsl/ISA+20)..and in my 'yoof' before I discovered my own mortality I made trainees do them too. I have had Training captains who knew me well and who I knew well fail engines on things like Barons etc at < 100 AGL with the gear on its way up and have happily flown away...at training weights.

And I have had a bunch of real engine failures both in piston twins and jets.

Not to brag but I think I am qualified to asses risk and set safety guidlines on assy training in GA aircraft...certainly when I am paying for it.

When I come back to Oz on holidays and renew my Oz MECIR just to keep it valid, and so I can fly my Bonanza IFR when required, I use people like Chesty (John Chesterfield) at YBCG. An absolute gentleman and with SOOO MUCH experienced that he doesn't question my attitude to what we are about to do....in fact he embraces it...that's called maturity and experience. I would not get in a piston twin with the average flying school ME instructor. I did once about 10 years ago...never again.

:ok:

[Centaurus]

Maui. When using the mixture, you do have the ability to restore, and within a poofteenth of a second of the time it would take with throttle

Aircraft gets airborne, gear selected up, blue line attained when instructor cuts the mixture. Student whacks on full wrong rudder (been there-done that) so instructor takes over control with IAS decaying alarmingly. Instructor has one hand on the control wheel real quick and then to re start the failed engine has to (with one hand) close the throttle of the "failed" engine, push the mixture control from ICO to rich, then rapidly introduce full throttle while at same time counteracting the sudden yaw caused by rapid application of full throttle on the previously failed engine.
And you tell me its all done in a poofteenth of a second compared with a simple throttle closure?

[rmcdonal]

So Centaurus, your saying that you can't just bring the mixture to full rich with the throttle at TO power? Real question.:confused: :confused: :ouch:

[maui]

Chimbu

I am impressed. Snap but in different areas. But I still would not be stood over. I would politely suggest you go find someone else to do it for you. And by the way it was in a testing environment that you framed the comment. Not a training environment.

Centaurus.

As you suggest, candidate gives you a boot full of wrong rudder. The throttle is still on the forward stop. Reintroducing full rich will give you intantaneous power. The engine will bark, but you will be on your way. And by the way if you do your failures without guarding the rudders, your a mug. My size 10's will overpower most candidates input fairly quickly when time is of the essence. Also as I said. Do it at the end of the endorsement, not the beginning. The guy should be on the ball. If you have incorrectlty asssesssed the level of his learning, perhaps you should reassess your own reading of standards.

Aerocat

A tad ultra conservative I think. May be appropriate if you are working out of real airports with bags of bitumen, however I woud never employ you for work in the bush.

Maui

[Led Zep]

I was told in no uncertain terms (also in company's ops manual) that if I had an EFATO but prior to Vyse I was to put it straight back down, runway or no runway. :confused:

[maui]

Led

Aero was talking about anything up to 200'. With both engines operating gear should be up and VYSE a thing of the past by then.

On the flip side. If you retact your gear before VYSE, you are asking for trouble.

Overconservative!

Maui

[Chimbu chuckles]

I agree in one area...when I was training on twins, be they piston, turboprop or the Falcon, the 'correct' rudder peddle was never going to travel backwards more than the length of the hair on a Bee's dick.

I never slam any control anywhere...if you wanted to end the excercise in a 'hurry' smoothly moving the mixture back to rich while controling yaw gave you full power very quickly. The fact that the throttle is 'wide open' means only one thing, there is little to no impediment to air being sucked into the cylinders by the pistons. The prop is windmilling, the magnetos are sparking, smoothly restoring the mixture restores power smoothly.

During the course of an endorsement you do get to know what the trainee is capable of and thus the engine failures get a LITTLE bit more testing near the end. But at NO POINT in a CAR 3/FAR 23 piston twin do you start pulling mixtures or closing throttles at 20' with the gear down....unless there is LOTS of runway and you WANT the trainee to land straight ahead. Personally I have never been blessed with training runways that long.

For readers not yet twin endorsed or low time ME.

In my view the only way to conduct a takeoff in a piston twin is;

Assess whether the aeroplane should fly with an engine failure after gear retraction...most will at reasonable weights and reasonable temps. Some have enough performance so you can fly away even having to retract the gear after the failure...Barons, C310s etc...I wouldn't like to try in a Duchess at MTOW....or in ANY piston twin at 40 deg C.

Ensure FULL power is attained early in the takeoff roll.

Fly the aircraft off the ground as soon as it wants to fly.

Accelerate in a VERY gentle climb to at least Vyse+10kts. Note I am NOT advocating flying level at 2'!!!

When you move your hand from the throttles to retract the gear you are committing to fly. On a short runway that might be as soon as you have a positive climb and on a long runway it might be 50-100'. If the engine fails before this control yaw and close the throttles and land. Too many pilots break this rule and end up arriving inverted.

Climb out at Vyse+10-20kts or cruise climb. Speed is ESSENTIAL not altitude. DO NOT reduce power to some BS 25/25 setting...leave everything all the way forward.

At the higher speed you'll need less rudder to control yaw and you have 'ample' time to carry out the memory items and assess whether the aeroplane will actually climb away and allow a circuit and landing while you gently raise the nose and climb with the speed VERY gently reducing to Vyse.

When the airspeed falls to Vyse you lower the nose and peg it...trim and assess. If you are descending start looking for something soft and cheap to hit.

At this point if you are flying level, or just barely climbing, you can start to fine tune things a little to either achieve some climb or maximise what you are getting. Raise the dead engine up with about 5 degrees AOB...don't get paranoid about AOB just raise the dead engine 'a bit'. This effectively reduces the 'arm' through which the assymetric thrust is causing yaw and will allow a little bit less rudder which means a little bit less drag which means a little bit more performance. It may turn 100'/min down into level, level into 100'/min climb or 200'/min climb into 300'.

Climb in a straight line and get at least 4-500' under you before you even think about turning....yes if there is a hill in front miss it:rolleyes:.

When you have a minimum 500' or higher, if you're in a good performing aeroplane lightly loaded you might climb to a proper circuit height, lower the nose and accelerate. Reduce power a little if you can and trim the aircraft. At this point in MOST light twins, even the very light twins like Duchess, you should be able to happily cruise at 100+kts with less than full throttle.

Having achieved level flight return to land. At this point turning either way is ok but you may get marginally better performance turning into the live engine...the main thing is a balanced turn.

On base and finals don't be in a rush to slow down to much and definately don't shove the gear out turning base and fly like you might on two engines. Curving around base at Vref + 20kts and slight reduced power at 400-500' should have you comfortably around blue line speed if you need to GA. At 300' on finals select gear down and maintain power and ROD...the gear will start you decelerating nicely towards a NORMAL Vref either flapless or with only approach flap.

At this point you are NOT going to go around!!!!

From here on you are just playing power off against the desired speed reduction to arrive at the round out and flare at a normal Vref (maybe a few knots faster) and then close the throttle in a normal way and land in a normal way. You do NOT land at 'Blue line' speed and Vmca is irrelevant. At typical appoach power settings using the above technique you will stall long before reaching 'VMCA'. Vs is not affected by being on one engine so you're landing speed is not effected either. Above I said you might land a few knots faster than normal. I say this not because a few extra knots is required because it is not...but on one engine you tend to hang on to the speed subconciously and a few extra knots is not worth worrying about or trying to lose by any means available...just land a few knots faster and be happy.

You shouldn't but if you do end up a little lower than you want you have the extra speed in hand to gently raise the nose and correct without having to add any, or at least much, power.

[maui]

Chimbu Chuck

We are in heated agreement. I totally endorse you comprehensive discription.:D

I do not believe that at any point, I advocated the 20' gear down cut. Appropriate height and time would be a more accurate description. Horses for courses.

What I cannot understand is the oft quoted concept expoused by the likes of Aerocat, wherein they will commit a basically serviceable aircraft to the junk yard, when it is possible to safely salvage the situation.
From memory the certification requirements are, among other things, that the aircraft should be able to achieve 1% at 5000' ISA. Given that level of performance, a properly executed recovery at sea level (or near to) will pose no problems, unless climbing toward rising terrain tree's etc. Granted there may be some airframe degradation, but if the aircraft is damaged bad enough to erode the performance significantly, one should not be putting his signature on the maintenance release.:ugh:

On the matter of standover tactics.:=
You and I are about to fly together. You in the LHS me in RHS. This can only be because you want something that I can give you, be that an endorsement, a renewal of an Instrument Rating or Instructor Rating, or the issue of some certification. this would be in my role as an ATO/FOI/Approved person/Chief Pilot/Chief Flying Instructor or any combination thereof. I have been approved and delegated by the regulator to conduct such operation.
Should you choose to dictate to me how I am to conduct such training/test, I will suggest you get someone else to do it for you, cos I will not. Regardless of the terms or what I intend to do/not do, and your considerable experience notwithstanding.
If you choose to take exception to my refusal to fly with you, you may:

1) Take your business elsewhere
2) Take the matter up with my superiors
3) take your complaint to the regulatory authority.

Maui

[Bula]

Maui I have to agree with Gimbo on this one, though my reply will be to politely open the mixture/throttle up and have a discussion.

I am sure you are good at what you do as you do continue to do it everyday BUT one thing you must learn is that even though you are the "captain" you can and will learn from the person in the right seat (or left in this case). To assume you know better if often fool hearty and most likely dangerous. Alwya keep one ear and one eye open and you never know what you may pick up sometimes.

I have done this before and will continue to do it. That is both listen and on the odd occasion put my foot down. I will not accept an engine failre if I deem a situation to be dangerous and am more then willing to discuss in the air and/or on the ground and usually do prior to the flight. This draws the "safety line" in the sand and pretty much tells me what sought of person you will be to fly with in a "Check and Training" role.


Many people are set in the ways they conduct themselves on tests, and good bless his sole, have brought highly experienced people to their unfortunate deaths. As for destroying the aircraft, well lets just say you can do what you can do but when it hits the fan are you landing ahead..... or just further ahead? The 1% is not always the case as we all know... have you flown a Twin Comanche lately at ISA +25?

[maui]

Bula

I think you misunderstand the thrust.

This is not a Captain F/O two crew, line operation/crm, issue we are talking about.

The syllabus and standards required are mandated. This is not a democratic set up.

The regulator sets the requirements and delegates an individual to administer said requirements, be they check or training.

Go do study/exam at a university. Do you get to determine how the syllabus is administered? Do you get to dictate how the exams will be run?

With regard to the Twin Comannche at ISA +25. (Not in the last 35 years)

Isn't the PA30 limited for IFR ops. (1% requirement).

What is the useful load extracted from the P Charts/POH in those conditions. 3/5th of 5/8ths of FA I would suggest. Chimbu said it all. Do the procedure and if it is going downhill pick your soft spot, but do not ASSUME that it will not operate.
Maui

[Chimbu chuckles]

Sounds fair:E

I have no real problem with aerocat's limit although I limit it to 200' in a training/checking environment. Note he, and I, sad "with the gear down'. Maybe he flys Aztecs with only one hydraulic pump..or he's used to Seminoles with at best anemic performance...or maybe he has only flown off long runways.

In a training or checking environment I see no point in low altitude simulated failures...the accident statistics bare this out too. With the gear up at 100'/at or above Vyse he probably would be as happy as anyone to continue.

I have no problem with gear up before Vyse either. Often it is a good idea if the runway is of limited length. It allows you to accelerate to Vyse quicker and if you lose one before Vyse you put it down on it's belly and slide to a stop off the end of the runway...better that than risk snapping off the nosewheel on rough ground and flipping. I wouldn't advocate that at Mascot but I would at Redcliffe.

Some aeroplanes, like the Twin Commanche, 'wheel barrow' if you try and hold them on the ground until Vyse. If you are going to be off the ground below Vyse you may as well have the gear up minimising exposure time to an engine failure.

At several airstrips I can think of I used to get airbourne below Vmca and accelerate nearly level in C402s. Before anyone goes ballistic YES I agree that is extreme and YES taking 402s into such a strip is probably not all that clever...but 'we were bush pilots once... and young', to paraphrase a movie. And No I am not going to tell you how to get a loaded 402 into the air at really low speed off really short airstrip.

As to the certification requirement of 1% at 5000' in ISA.

Well that is demonstrated by a test pilot in a brand new aeroplane and with the added bonus of shutting down the engine in a controlled manner and optimising everything.

It bares no relationship to a 25 year old Duchess, Seminole, Twin Commanche which may be being flown by someone of low experience and minimal recurrent training on a 35 degree day out of an 800-1200m airfield. The 'OH ****' factor is too high and without 6 mthly recurrent training the chances of such a pilot successfully coping are proved to be minimal by the statistics. As an example I had an engine failure in a 402 at 50' with the gear retracting approaching Vyse once. No room to stop without hitting jungle at high speed. It took 4 minutes to get to 500' over the water passed the trees and I was very lightly loaded. I never got above 500' because of low cloud and heavy rain.

I was flying piston twins full time within the check and training auspices of a 3rd level airline, 6 mthly recurrent checks, and a training pilot as well. I think no one would argue that a 402 has more performance on one engine than a Seminole...although it aint much more:ok:

Barons, C310s, Chieftains, 402s etc do have better performance than typical training twins but you pay for that performance with more challenging handling assymetrically.

To return to the thread topic, and at the risk of upsetting Centaurus who has considerable (LOTS and LOTS) experience in this area.

In my view failing on the mixture v failing on the throttle is not the fundamental problem or greatest danger in assy training.

Altitude/speed when the failure is given, what happens next, and the knowledge and competence of the trainer are the main factors.

There are no circumstances where I can accept failing engines below 100' and at less than Vyse+10kts with the gear up in a training/checking environment. 200' is better.

The trainer/checker MUST have significant real multi experience...that precludes all low time instructors hour building.

The individual must have demonstrated ability and knowledge. This is actually tougher than it sounds...you would not believe the crap I have heard espoused by people with CASA approvals...and from CASA FOIs for that matter.

When I was tested for each type specific twin training approval I was tested by people who were VERY experienced on type and grotesquely experienced in general and VERY current. I also gained my individual approvals within the auspices of 3rd level airlines rather than the 50 ME TT/10 on type BS you see at flying schools and as a result had 500 to 1000 hrs on type in the earlier days and at least 200 on type later on. The Falcon was a different story.

Because of the skill, knowledge and experience of the people who trained me I got put through every drama a student could come up with in a 'controlled' environment. No trainee I ever experienced took me places where these guys hadn't taken me first...in fact not even close:uhoh:

I don't think there are any people left at CASA with the currency, knowledge, skill and experience AND the desire to pass it on. There would be relatively few left in Industry and I am not counting those that may have the desire to teach extreme stuff to a potential ME Instructor but shouldn't be because they don't have the knowledge, skill and experience themselves. There are a few though.

In my view twin training is sufficiently serious and the accident rates high enough that short of good Level D equivalent sims being used it should be so hard to get the training approval as to be bordering on impossible for the average flying school instructor.

[Tinstaafl]

Hmmm....Oz rules - but not necessarily what the aircraft was originally certified under.

1% climb up to 5000' DH is an Oz requirement - and only applies to *IFR* light twins -hence the somewhat unique Oz IFR weight limit. VFR types only had to be able to maintain altitude.

Elsewhere in the world eg the US FAR 23 under which most (?) were originally certified they only had to have their climb performance 'demonstrated' (<6000 lb MTOW). That can be a negative climb performance. Above 6000 lb TOW then the required climb performance isn't much: along the lines of 0.0027 x the sqr.root Vs (or similar. Can't remember the exact details).

I'm with CC on this with relatively minor variances in technique.

Blue line is the gear up point & that, in turn, is my attempt-to-fly point. I delay gear up if it's a long runway with plenty of room to land on the remaining and get the gear up as soon as I have +ve climb if it's a short/obstacle limiting strip.

I don't have a problem with mixture cuts because I teach (well, taught...) an expectation to land ahead for a failure below blue line & only try to go once gear is selected UP. Gear selected UP is the decision point between landing or trying to fly (but still have a Plan B to force land anyway).

The engine has everything ready to produce maximum power other than adding fuel to the airflow.

As others have mentioned it's prudent to guard the rudder pedals to prevent misapplication. No different to guarding the controls when teaching landings, spin & stall recovery etc.

[maui]

Chimbu Chuck

Couldn't agree more. Particularily in relation to the requirements for Multi training approval. In my view this is almost entirely the cause of the decline iin standards and knowledge. Same goes for Intrument Training for command IR.

Sadly the regulator has blood on its hands in this regard.

Maui

[Led Zep]

Led

Aero was talking about anything up to 200'. With both engines operating gear should be up and VYSE a thing of the past by then.

On the flip side. If you retact your gear before VYSE, you are asking for trouble.

Overconservative!

Maui
I misread the post! :O
I was taught a similar thing at a flying training school (200ft for one rwy, 300ft for the other) but that was because we'd have 3500m of bitumen to land on. On shorter strips the determining factor was Vyse.


Chimbu Chuckles, great posts. :D
I suppose I should consider myself lucky I was taught by someone like those you describe?

[AerocatS2A]

I was actually just restating what I understood Chimbu chuckles to be telling his prospective testing officer. If it got mangled in translation, that is my fault.

[Chimbu chuckles]

You understood me perfectly:ok:

Just a few days ago I was discussing this very thing with a mate who is a senior checker at Ansettstar.

He recounted the time when he was doing a flight test in a seminole 20+ years ago and having had the engine fail he had it flying straight and level at full throttle but couldn't get anymore out of it. The 'instructor' had pulled the gear circuit breaker without saying anything and as a result the gear did not retract and no lights showed on the panel.

Someone like that needs taking out the back of a hangar and 'educating'.

[maui]

I'll come and help.

[Bula]

Maui, I agree with you please dont get me wrong. I think more so I'm talking about methods above and beyond that reqiured which impose an unnecessary danger to both pilots onboard.

I have found by talking about this before the flight helps, especially when 2 experienced pilot are involved. :ouch: Saves the black eye :E

[Centaurus]

I wonder about this business of delaying the raising of the gear until you assess you can no longer land safely ahead from an airborne situation.

Having read quite a few POH, while there is advice on wotif you have an engine failure at various points on take off - I have yet to find manufacturer's advice which recommends deliberately choosing to delay raising the gear in order to let you throw it back on the deck.

My thoughts are regardless of the length of the runway you should retract the gear after lift off as soon as you have a positive rate of climb - same as jets. This enables quicker acceleration to safe single engine climb speed.
There is always going to be a window of several seconds after take off where an engine failure is going to require a pretty quick decision one way or the other. And if that decision is based on whether or not you have selected gear up or whether or not you have reached blue line, then now throw in your assessment of runway length remaining to plonk it down - wet or dry runway - night or day - seems too complicated to me.

A night take off with gear left down and thus longer time to get to blue line, is fraught with hazard in terms of judging a bunt-over single engine flapless landing with no anti-skid. Not for this little black duck.

Blue line is a meaningless figure as a decision figure. It is best single engine rate of climb and no more than that. It is not a decision speed quoted in any manufacturer's POH. Lose an engine in a Seminole 5 knots above the blue line of 88 knots and you will be unpleasantly surprised how quickly you have done in 10 knots below blue line due to the drag of the failed engine.

Far better to keep things simple and accept there is an inherent risk with light twins if you lose an engine shortly after lift off. It is all about rudder control and that means adequate speed. Just accept that the sooner you get the gear up after lift off and accelerate to a safe speed aabove Vmca the safer you will be - if you are competent. I am reminded of a ATSB report of a Seminole accident at Ballarat (?) where the instructor cut the mixture around 200 ft in excess of blue line but with the gear left down in accordance with the mantra of leaving the gear down until you can no longer land ahead. The student had no problem with the engine failure as he had speed to spare and he decided to continue. The instructor shouted he should abandon the take off climb as the decision point was agreed at gear up. The student hesitated a nano second so the instructor took over, closed both throttles, lost control and stalled in his attempt to land straight ahead. The wing broke off on impact and both pilots were lucky there was no fire.
What a total balls up by the instructor. I leave the reader to figure out who was to blame for a training accident involving to perfectly serviceable engines, two appropriately licenced pilots (student had 17 hours on the Seminole), and perfect weather. The instructor blamed the student for slow reaction!! And it was the bloody idiot instructor that was the direct cause of the accident.

[Chimbu chuckles]

I agree with all that...but would caution against any decisions being based on 'like we do in jets'.

There is just too many differences in handling and performance. Viva la difference is my attitude...one of the things that boils my blood quickest is innappropriate SOP transference between FAR25 certified jets and CAR 3, or if you're really 'lucky' FAR 23 GA types. As the average light twin, and some not so light twins, AFMs say...if you do everything right you will get a maximum ROC or a minimum ROD.

In my view piston twins offer a great deal in exchange for exposure on takeoff which is really not hugely greater than a heavy single...if you're prepared to pay the 300% cost premium.

That is the bottom line in my view...cost...the overall statistics suggest that any increased safety of one over the other is really to vague to actually quantify with any certainty. That is a shame because it should be a no brainer...I guess the no brainers are to blame.

As far as the holding onto the gear until blah blah is concerned I think it just stems from people being asked by the boss why the just parked an expensive twin on it's belly 50m from the other end of the runway.

Certainly I agree that with most twins, most of the time, the sooner you pull the gear up the better.

In fact, thread creap aside, I pull the gear up on my Bonanza as soon as + climb achieved. It's a whole other set of considerations and mindsets but leaving the gear down on any retractable has important considerations that many people are unaware of....given the questioning looks I get from people who fly my Bonanza.

Once I explain why I retract the gear quickly and demonstate it the light comes on.

[Centaurus]

CC. That is the bottom line in my view...cost...the overall statistics suggest that any increased safety of one over the other is really to vague to actually quantify with any certainty. That is a shame because it should be a no brainer...I guess the no brainers are to blame.

Dead right and in fact some years ago Mac Job the well known flight safety aviation writer made exactly the same point as you have - that is light twin engine safety is tied to cost.

[APMR]

Always an interesting subject.

It is rubbish to suggest that it is more kind to the engine by cutting the mixture, as maui does here:


Conventional wisdom in the past was that a mixture cut was easier on the engine as the loading stays positive. If the throttle is pulled abruptly backloading occurs, which can do nasty things to dynamic balances. Additionally if the engine is of the geared variety the lay shafts take a caning.



The two methods of simulating the failure are in fact, almost identical (from the power loss point of view). Both rapidly deprive the engine of the heat energy that would be converted to mechanical energy. Following the loss of power, you have the situation that is referred to in numerous different ways by pilots, but which all mean exactly the same thing:

- "Windmilling"
- "Backdriving"
- "Backloading"
- "Negative torque"

Chimbu said:

Morons have caused piston twins to have the reputation they have not the aircraft themselves.


Sadly, I have to agree with this. 8 children lost their fathers a few years ago at Jandakot because the pilot, having lost an engine just after takeoff, was in too much of a hurry to get the aircraft back onto the ground. The aircraft was maintaining height (albeit very low) at speeds around the blue line but a steepish turn when attempting to get back to the runway took the aircraft too far back on the power curve and a collision with the ground (and fireball) was the inevitable result.

The significance of NOT TURNING when assymetric is nowhere near emphasised enough. It should be hammered into multi pilots as much as the "don't turn back" message is hammered into single pilots for when they lose their engine just after takeoff.

On this point, the opinion of Chimbu was:

Climb in a straight line and get at least 4-500' under you before you even think about turning....yes if there is a hill in front miss it


On VYSE: too many pilots have too much regard for this number when considering a multiengine takeoff. It is revered as an almost magical number that determines whether you will be able to fly or not. Too many pilots have the view that "if you lose one before blueline you won't climb".

That view is rubbish and pilots that hold it are firmly in the moron category that Chimbu referred to earlier. If you are one of them I ask you: what about VXSE? That speed is always less than VYSE (by almost 10 knots in the case of one type) and because of the relationship between these speeds, if you can climb at one, you will climb at the other - and if you can't climb at one, you won't be able to climb at the other.

Readers of this post may be interested to know that the blue line is NOT marked on the ASI to assist pilots in the EFATO case. When the FAA mandated the blue line in the early 60's it was for the case where the aircraft lost one in the cruise.

Centaurus is right on with this comment about blue line:

Blue line is a meaningless figure as a decision figure. It is best single engine rate of climb and no more than that. It is not a decision speed quoted in any manufacturer's POH. Lose an engine in a Seminole 5 knots above the blue line of 88 knots and you will be unpleasantly surprised how quickly you have done in 10 knots below blue line due to the drag of the failed engine.


Finally, hands up all those whose drill, following an engine failure after takeoff with flaps extended, is to retract the flaps immediately after retracting the gear? (As part of the drill, in other words).

If you put your hand up then I suggest you read the manufacturers instructions re engine failures after takeoff - you may find that the POH stipulates that you leave the flaps alone - until reaching a "safe height".

The POH for a Cessna 400 series type stipulates exactly this - but how many of us have been trained to follow the "mixture up, pitch up, power up, gear up, flaps up" drill?

[novicef]

I don't have a Seminole POH, do you know off hand if the drill for EFATO is also Pitch Power gear flap or does it's POH state that flaps be left till a safe height? What is a safe height?

[Icarus2001]

From the Beechcraft Baron 58 POH P/N 58-590000-39 Issue Oct 1984 revised October 1990.

Page 3-5.

ENGINE FAILURE AFTER LIFT-OFF AND IN FLIGHT.

1. Landing Gear and Flaps - UP
2. Throttle (inoperative engine) -CLOSED
3. Propeller (inoperative engine) - FEATHER
4. Power (operative engine) - AS REQUIRED
5. Airspeed - MAINTAIN SPEED AT ENGINE FAILURE (100 kts MAX) until OBSTACLES ARE CLEARED

...checklist then goes on to talk about securing failed engine.

Interesting that the manufacturer advocates flap up at step 1 but does not talk about clearing obstacles and increasing speed until step 5.

The "five ups" are not perfect but they work most of the time.

[wdn]

cc said


Accelerate in a VERY gentle climb to at least Vyse+10kts. Note I am NOT advocating flying level at 2'!!!


and

Climb out at Vyse+10-20kts or cruise climb. Speed is ESSENTIAL not altitude. DO NOT reduce power to some BS 25/25 setting...leave everything all the way forward.

At the higher speed you'll need less rudder to control yaw and you have 'ample' time to carry out the memory items and assess whether the aeroplane will actually climb away and allow a circuit and landing while you gently raise the nose and climb with the speed VERY gently reducing to Vyse

i must respectfully disagree. IMHO you should fly at Vy (Vx for obstacle clearance if necessary). that provides the highest altitude should you suffer an engine failure. you must remember that drag is proportional to the square of the airspeed so the higher the speed, the quicker you will slow down anyway. much better to be at 400' at 85kts then 250' at 100kts in something like a duchess when the engine stops.

RAAF procedures are as i describe and it certainly is the beechcraft recommendation.

[Oktas8]

IMHO you should fly at Vy (Vx for obstacle clearance if necessary). that provides the highest altitude should you suffer an engine failure.

Piper recommend this for the Seminole too I think. However, I teach to climb at an attitude corresponding to the more conventional Vyse+10kts or so, because that is the same attitude as a Vyse climb on one engine. That is, there's no significant attitude change required if an engine fails.

If I have an obstacle to clear, then I will maintain Vy or Vx until a safe height, as per manufacturer's recommendation. But I specifically remind myself that I'll need to lower the nose dramatically in the event of an EF. This will also necessitate turning early or landing ahead because I won't clear the obstacle. Not a "normal" take-off (for me at least!)

I too am interested in whether it damages the engine to apply mixture ICO -> fully rich with the throttle open. It's a pity no-one seems to know.

Thanks to all the very experienced pilots who have made posts here - CC & Centaurus among others. I (we?) have appreciated your taking time to pass on your knowledge.

[wdn]

okats8, if you fly a single, do you climb at the gliding attitude so there won't be a pitch change if you suffer an engine failure? :p

airspeed is life but altitude is life insurance....

[Chimbu chuckles]

wdn Vy and Vx are certification speeds (test pilot territory) not really applicable in day to day flying. They were speeds born of some certification requirement and have, like so many things in aviation, taken on a life of their own.

Think about it. A 50' obstacle exactly at the end of the TODA.

Think also about how low 50' is.

You'll be above 50' before the gear is up.

And yet we see pilot after pilot climbing away at Vy to some truly stupid altitudes...500'-1000' or even cruise altitude as often as not...cruise climb seems to be a mystery to many pilots.

It is, in my view, negatively reinforced by the diagrams you see depicting Vy/Vx in sundry publications. Usually a picture of a cessna standing on it's tail climbing over a tree....the scale errors of the diagram make it look like the tree is actually several hundred feet high and that, I suspect, is the psycological factor which starts pilots climbing at Vy to such completely stupid altitudes.

In my Bonanza Vy is 93 kts. Glide speed in the landing config is 90kts and glide speed clean is 110kts. At 93 kts the nose is hauled up so high that the view ahead is severely compromised. If you lose an engine in that attitude you'll be below 90ts in a heart beat and have to lower the nose dramatically in an attempt to get it back let alone 110kts. At an altitude of say 100' you will merely develope a very high rate of descent without the time to recover speed and its attendant manouever capability. You will then be faced with the ground arriving to smite thee in the face at some horrifying rate and a almost guaranteed very heavy arrival.

In a twin many of the same considerations apply but for slightly modified reasons. If you are climbing away in a typical piston twin at Vy in an effort to get lots of altitude 'quickly' in case of engine failure and you actually lose an engine you will need LOTS of rudder to control the yaw and need to lower the attitude dramatically to;

1/. stop further speed decay,

2/. regain a speed which will allow you to climb/maintain height while you sort **** out.

Given the extremely high oh ****!!! factor in typical real engine failures this is beyond the capabilities of many pilots and, in my view, is exactly how Vmca loss of control accidents happen.

In my Bonanza I get airborne, gear up, gently climb/accelerate to 110Kt asap. If I lose the engine at any point I need only to lower the nose slightly to maintain speed and look for something soft to hit. Once I actually have 110Kts the aeroplane is truly manoueverable and can look at turning left or right slightly for better opportunities if they exist. At 110kts my wing really comes alive and I get initial climb rates of 1000'/min at 110-120kts...with nice cool CHTs as well:ok:

The same applied when I used to fly Barons etc. Accelerate in a gentle climb looking for that cruise climb 'sweet spot' and if you lose an engine you have a nice buffer above Vyse (and that may not be the blue radial painted on the ASI. Control initial yaw with rudder (you'll need a lot less at the higher IAS) gently lower the nose a small amount to maintain speed and carryout the recall items- mixture/pitch/power up, wheel ups/flaps up/ identify, verify, feather, fuel.

I have yet to see an airport/airstrip in my career that required Vy/Vx

Editted for spooling...again.:ok:

[Oktas8]

Yeah. Wot he said. :ok:

In my reading of accident reports, most fatalities arising from EFATO in a light twin were completely avoidable. For example - struggling to gain height at Vxse or Vyse, then hitting a hill? Very rare scenario. Another example - aircraft committed to a forced landing, pilot closes both throttles before touchdown? Again, very rarely fatalities from this scenario.

What I have read many cases of, is pilots maintaining an excessive pitch attitude when asymmetric, with a quick speed decay to below their personal Vmc. That almost always results in multiple fatalities. I have seen intelligent and current students do it in training, and had to take over control. Why do people do it? Without having experienced a real EF, I agree it's the "oh bugger" factor, coupled with a psychologically overwhelming desire to climb away at something that looks "normal".

While I agree with your airspeed - life axiom, I consider that there are statistically safer ways to fly a light twin where terrain is not limiting.