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Big Pistons Forever
15th Mar 2015, 21:16
This comment on the EFATO thread got me thinking.

That's why we should expect it - on every take off. Be surprised if it keeps running!


Personally I think flight training spends an outsized amount of time and effort on bad occurrences that are quite rare and not nearly enough time on bad occurrences that are quite common.

If you are sitting at the edge of your seat waiting for the engine to fail on every takeoff and then are "surprised" when it doesn't than I think you are ascribing a much higher probability to the event than it warrants.

This does not mean you ignore the possibility of it happening. I think every pilot should review the EFATO vital actions prior to every takeoff and pay attention to the terrain surrounding the airport but an EFATO is just one of the many negative eventualities that could occur during the flight, many which are much more probable ( eg Carb icing).

The risk of most of these eventualities can be mitigated by a disciplined approach to flying, including good pre flight planning (Wx, NOTAMS, Fuel Calculations etc), effective checklist use and a good look out both in and out of the cockpit.

If those precautions are applied than an EFATO is very unlikely. If you look at the accident statistics the Least Common scenario is for an EFATO in for an aircraft that has

1) no outstanding maintenance issues,
2) Has sufficient fuel, no contamination, and from a correctly selected tank
3) Shows no anomalies during a complete and comprehensive runup
4) Was checked for Carb ice before lining up for takeoff, and
5) The engine gauges where in the green and the engine was developing full static RPM at the start of the takeoff role.

The accident statistics show that up to 80 % of SEP engine failures were caused by the actions or inactions of the pilot with fuel exhaustion/contamination/mis-selction and carb icing accounting for the majority of the engine failures.

I think it is important that my list of 5 actions are wholly in the control of the pilot and will dramatically lower the risk of an engine failure at every stage of the flight.

If you are slap dash about your walk around, rush through the runup and don't use a disciplined check list methodology, and then go out and do a bunch of PFL's; yes you will be safer than doing no training but you will be acquiring skills to deal with the engine failure you very likely have caused.

Engine failures do occur but I would strongly suggest that if you are serious in preparing yourself for this eventuality your training should start with reviewing actions that will reduce the possibility of the engine failure and then progress to practicing the actions that could restore power in the event of a failure and only then work on actually flying the forced approach manooever.

Well I am done for now but I expect this should engender a lively discussion. :ooh:

Shaggy Sheep Driver
15th Mar 2015, 21:56
Big Pistons, I marvel at your faith in the collection of stressed rotating and reciprocating parts, held apart by a microscopic film of oil without which it will destroy itself within seconds, that comprises an aircraft engine. And we are talking not modern highly-developed, superbly engineered, highly computer-controlled very well developed modern automobile engines, but an old technology air cooled 1930s engine similar to what used to power classic Brit motorbikes, only larger.

You say:

the Least Common scenario is for an EFATO in for an aircraft that has

1) no outstanding maintenance issues,
2) Has sufficient fuel, no contamination, and from a correctly selected tank
3) Shows no anomalies during a complete and comprehensive runup
4) Was checked for Carb ice before lining up for takeoff, and
5) The engine gauges where in the green and the engine was developing full static RPM at the start of the takeoff role.

The engine that part-failed on me ticked all those boxes. So did the Lycoming in the PA38 in which the guy I knew died when it stopped at 300 feet.

horizon flyer
15th Mar 2015, 22:10
There are so many design faults in a Lycoming it is a surprise it runs for any length of time. So always be prepared for it to quit or run at reduced power.

Lycoming say they need to be run 40 hours a month to meet TBO and any failures are down to pilot handling ya!!.

So take care.

Shaggy Sheep Driver
15th Mar 2015, 22:18
And of course aircraft engines run at far higher power settings for much longer than a car engine does. At take off it runs at full power from near-cold for quite a long time. So even if it was as well engineered as a car engine (it's not - it's crude old technology) it would be less reliable.

Pace
15th Mar 2015, 22:47
Engine failures do occur but I would strongly suggest that if you are serious in preparing yourself for this eventuality your training should start with reviewing actions that will reduce the possibility of the engine failure and then progress to practicing the actions that could restore power in the event of a failure and only then work on actually flying the forced approach manooever.

BPF

Aviate Navigate communicate ? Surely an engine failure at low level means you should be putting your full attentions into flying the aeroplane and selecting a suitable landing area not head down fiddling with mixture controls, fuel selectors etc ? that surely is the way to loose control and crash?
Too many fatal accidents are caused by pilots not aviating and putting their attention elsewhere trying to restart an engine at 200 feet is a big mistake

Pace

Big Pistons Forever
15th Mar 2015, 23:17
The engine that part-failed on me ticked all those boxes. So did the Lycoming in the PA38 in which the guy I knew died when it stopped at 300 feet.

From what I recall the engine partial failure left you with enough power to maintain level flight and re-position for a landing. I do not mean to make light of the fact that you successfully dealt with a very significant emergency but the engine did not "fail" in the way people are talking about in the other thread.

As for the Pa 38 crash the accident report stated the cause of the crash was


The most likely cause of the engine stoppage was stiffness of the fuel selector valve causing it to be in an intermediate position, reducing fuel flow to a level too low to sustain continuous engine operation.


I would suggest that there was at least some indication that the fuel valve was not working properly and thus the potential to have prevented the engine failure was present. I also find it hard to believe that an engine starved of fuel did not give some indication that there was something wrong on the takeoff run.

I think it is also very unfortunate the accident report stated that there appeared to be no attempt to lower the nose after the failure. The climb attitude was held until the aircraft stalled, although tragically the pilots only reaction appeared to do the least important thing of all, make a radio call.

I realize that 2 people died in this accident and my remarks may seem insensitive but I believe this accident has lessons that should not be glossed over.

Engines with properly selected fuel selectors don't stop. If there is any doubt about how the selector feels or whether it is properly positioned than you should not takeoff.

As has been already mentioned in many other threads the first action by the pilot when confronted by an EFATO must be to lower the nose. If you do nothing else but keep the wings level you will probably survive, but letting the aircraft stall at low altitude is a death sentence.

fireflybob
15th Mar 2015, 23:34
Just interested to know which PA38 accident we are talking about here?

Slightly off thread I find a lot of pilots do not turn the fuel selector to OFF at the termination of a flight and many are not aware of the safety catch to do so. This action confirms that is physically possible to select OFF, reminds the pilot how to do so (both actions required for fire in flight or for crash/committal checks in event of engine failure) and procedurally is a checklist item.

The most likely cause of the engine stoppage was stiffness of the fuel selector valve causing it to be in an intermediate position, reducing fuel flow to a level too low to sustain continuous engine operation.

1) no outstanding maintenance issues,

Debatably this was an "outstanding maintenance issue"? Or maybe this issue should have been rectified before flight.

TheiC
16th Mar 2015, 07:21
The last two SEPs which apparently reputable UK flying schools presented to me for flight had long-running engine maintenance 'issues' which the schools concerned knew about and had chosen not to resolve. One of them had two problems each of which was unacceptable.

I don't remember that sort of thing being a feature of my (halcyon?) days as an FI. I do wonder if it is perhaps quite common nowadays...

ChickenHouse
16th Mar 2015, 08:18
First of all I would like to draw attention to widen scope. Risk mitigation of EFATO is probability and severity, so high degree of attention is to be spent mostly for the second.

Yes, the 5 list does cover a great number of fatalities reasons and I often find myself shaking head when reading accident reports, but, being a pilot means also to do mistakes, frequently. The beauty is to do only the once not killing you.

In our current world of full-insurance-coverage thinking it may appear archaic to be aware of death, but this also make part of the soul of a pilot (in contrast to a flying bus driver). So what is all that excitement about? I do a fatal mistake, I die, so what? The only thing to take care of is to not hurt somebody else upon doing so.

Shaggy Sheep Driver
16th Mar 2015, 10:02
Big Pistons, you may read elsewhere in one of these EFATO threads that partial engine failures lead to more deaths that complete failures. Having had one, I concur.

The PA38 I referred to did indeed have a faulty fuel selector, but there is nothing in the AAIB report that says that should have been noticed by the pilot. My understanding is that he moved the selector handle to the correct position, but wear in the mechanism meant the tank was not correctly selected.

One guy died in hospital after the crash - the pilot. His passenger received terrible burns but survived.

Where I would question that pilot's actions prior to T/O is that he changed tanks then took off, so any problem with that tank - fuel, selector, or whatever, wouldn't manifest itself until he was in the air. I used to fly that very aeroplane, and I used to change tanks before the power checks, so plenty of time for subsequent problems to happen while we were still on the ground (they never did, but that was when that aeroplane was much newer).

Whatever, in my book one should be EXPECTING an engine fault at any time in flight, but especially at T/O. This doesn't mean 'sitting on the edge of the seat', merely not being surprised (OK, not being overwhelmingly surprised) when the power dies away at 300 feet.

maxred
16th Mar 2015, 10:07
I think there is an issue here, comparing apples with pears. There are distinct markets, the club rental market, the owner/operator market. Both hinge on knowing the aeroplane. The owner has a distinct advantage. He, to a certain degree, knows what he has done to his aeroplane, (or should do), therefore in the frame of EFATO, he should and could do all he can to mitigate the occurrences. Proper/correct maintenance regimes, proper and diligent walk rounds, adherence to owner SOP.

The renter relies on someone else having done all of the above, and places faith on the rental organisation to have a duty of care. I have seen, and been in, some right buckets, but I had the go/no go decision. I have seen some poor decisions made by owners, and again have invoked my go/no go decision.

Life is chance, therefore, if we could predict when the engine may fail, we would all be very rich. I do not think stats exist of failures in the two categories mentioned above, but I would maintain that pilot error is still the main cause of death, even when the engine quits. We generally do not hear about successful engine failure landings, but we tend to here all about them when they go wrong.

Rod1
16th Mar 2015, 10:14
"Slightly off thread I find a lot of pilots do not turn the fuel selector to OFF at the termination of a flight "

Personally - I never do this as I think it is safer to keep it on.

If I walk up to the aircraft and it is sat in a pool of fuel I am not going to fly it! If I switch the fuel off I may not find out about the issue till later...

The fuel selector often has no maintenance schedule. I know of a number of aircraft that have suffered fuel selector failure at the point of max fuel pressure - normally just after takeoff and the pilots have been killed or burned - and one when the pilot was sprayed with fuel but got the cub down and it did not go bang.

I check my selector every 3 months. This confirms it is working.

Rod1

ChickenHouse
16th Mar 2015, 10:25
Slightly off thread I find a lot of pilots do not turn the fuel selector to OFF at the termination of a flight.
I never do. As Part of Pre-flight I do check it is movable and turn it one time left-right-both-off, so at latest upon engine start I have a fair chance to see trouble on the ground. If I would turn it off, fuel may evaporate during parking and the lines may not be fully filled (had this once a couple of years ago), plus with open valve any small leakage in the fuel feeder will be smellable.

maxred
16th Mar 2015, 10:32
Ditto, I always leave my selector on a tank, never put it to OFF.

Gertrude the Wombat
16th Mar 2015, 12:38
So even if it was as well engineered as a car engine
I've had several car engines fail on me and 0 aero engines.

S-Works
16th Mar 2015, 12:52
I have had three in certified Pistons, 1 in permit Rotax and 2 in turbines.......

ChickenHouse
16th Mar 2015, 13:09
I've had several car engines fail on me and 0 aero engines.
How often do you PFC your car?

Crash one
16th Mar 2015, 13:26
Big Pistons, I marvel at your faith in the collection of stressed rotating and reciprocating parts, held apart by a microscopic film of oil without which it will destroy itself within seconds, that comprises an aircraft engine. And we are talking not modern highly-developed, superbly engineered, highly computer-controlled very well developed modern automobile engines, but an old technology air cooled 1930s engine similar to what used to power classic Brit motorbikes, only larger.

I had a BSA 650 in the early 60s that never let me down once, from one end of the country to the other in some pretty filthy weather at times.
I now have it's bigger brother in the form of a Continental C90 up front and it too has never missed a beat in the 7 yrs it's been pulling me around. 3100 hrs in the book.
I've just fitted an electric fuel pump which the a/c didn't have before. If there is a time when I might expect an EFATO it will be the next time I leave the ground. There will be a considerable amount of taxi time & full power run ups before that happens.
I wonder how many failures occur just after maintenance, and how many are maintained by the owner, (permit types) versus maintained by commercial ops?

Gertrude the Wombat
16th Mar 2015, 13:54
How often do you PFC your car?
Well yes, that would have caught one of them, I don't fly off in a plane with an oil pressure indication reading zero.

(Actually it was the tachometer reading zero, but that was, if I'd known the car's system well enough, an indication of an oil problem.)

fireflybob
16th Mar 2015, 14:51
Ditto, I always leave my selector on a tank, never put it to OFF.

Then how do you know you can turn it OFF if you need to?

Rod1
16th Mar 2015, 15:03
I have had two engine failures (one partial but could not maintain height). Both were due to professionally supplied parts or maintenance. In one case I had told the maintenance organization I thought there was an issue and had wasted significant time and money for no fault found till the other mag failed and I ended up on 1/2 a mag over Scotland (Robin DR400).

That is in around 1200 h, but both issues were in the first 600. I do my own maintenance now;)

Rod1

Shaggy Sheep Driver
16th Mar 2015, 15:12
The Chipmunk has 2 fuel pumps, both mechanical diaphragm types, in parallel. Both feed the carburetor simultaneously and one is used to prime the engine as well, using a manual lever.

If the one used for priming fails you'd know because you'd not be able to prime the engine. But if the other one failed you wouldn't know you were relying on just one until the first failed as well (at some point after priming), when the engine would stop!

maxred
16th Mar 2015, 15:19
Then how do you know you can turn it OFF if you need to?

Because I ripped out all of the fuel lines, replaced the worn gascolator, renewed the selector, and at the 50 hr, and each annual we check it. I also check it once a month. The comment was I leave it on after each flight. Given I am the only one that flies my plane, I am quite happy with it.

Mainly due to this incident

http://www.iasa.com.au/folders/Safety_Issues/FAA_Inaction/fueloffed.html

fireflybob
16th Mar 2015, 18:05
maxred, thanks! It's your train set so do as you think fit.

Regrettable though that accident was am not sure it proves much in the respect we are discussing. But I would prefer to read the whole accident report rather than a news article summary.

I can see some of the counter arguments to not turning the fuel off but in the training context I still think it should be taught.

maxred
16th Mar 2015, 20:04
Firefly, I agree that within the training context, all procedures should be taught in line with the POH of type. Generally training types, if such a thing exists, are designed to ensure that the unwary, do not get trapped. Therefore, on, off, on again, training rote, getting the student into the ABC mentality. As you progress though, particularly with older types of aeroplanes, certain idiosyncrasies crop up, often peculiar to model, and individual airframes.
The early Bonanzas, in particular, have some strange and peculiar fuel set ups. Therefore for me, I keep it on selected tank. At least I know the engine was running when I landed:8:8

9 lives
16th Mar 2015, 21:08
I've had three engine failures very low after takeoff. One, a fuel interruption, put me back on the remaining runway (I could not have made it past the end :D), another, at only a couple of hundred feet was ice crystals in the fuel, into the next field, no damage, and took off later when resolved. The last was the mouse nest of insulation from under the glare shield, being sucked from the air hose, into the venturi, with the application of carb heat, again, into a field, no damage, towed it home.

Very much worse has occurred during testing I was doing, but I was up high, and testing for it - it happened! Consider the tried and true C 180. Owner installs a STOL kit - yippee! Look at those high AoA's and steep departures it can do now (not safely). Then owner installs a larger carburetted engine - still no fuel pumps. Wow, it goes up even better now! But.....

When you combine the higher pitch attitude capability with a STOL kit, with the higher fuel flow demands of a bigger engine, you can get the plane into a very nose high danger corner, in which it will quit, and from which recovery to gliding flight is unlikely. The carb inlet is actually higher than the tank outlet - 15 degrees pitch up is in the danger territory. I agree, this is far away from the regular airport circuit technique, but there are pilots doing, it and I have done the testing to demonstrate that there is a much greater risk of EFATO doing this. Floatplanes are more vulnerable, as pilots are sometimes trying to outclimb terrain. A friend of mine, a very competent, though perhaps a bit complacent, friend of mine broke his back in the resulting crash - and he has heard my admonishments on this (beforehand).

So EFATO's are happily rare, and there are things you can do to make them even less likely. But, flying with "room" for them to happen without ruining your day, is a good idea when you can.

Chuck Ellsworth
16th Mar 2015, 21:23
To give a better idea of why extra speed is better than extra height immediately after take off here is a good example.

We were scooping water on a fire one day when I had an engine start to fail just after lift off from the water it happened just as I reached my start climb speed which was ten knots over the airplanes normal climb speed.

The extra speed gave me the inertia factor to allow me to scratch my nuts while I decided what I was going to do with the beast.

So... once I was sure I was doing the correct thing I first dumped the nine thousand pounds of water and feathered the prop......did the shut down stuff in the check list and flew seventy five miles back to home base....

....fortunately I got it shut down in time to save the engine because it had blown a cylinder and the piston had a big hole in it.

The Flying Pram
16th Mar 2015, 21:47
And of course aircraft engines run at far higher power settings for much longer than a car engine does. At take off it runs at full power from near-cold for quite a long timeBut those full power settings are quite frankly derisory. An O360 displaces nearly six litres, yet typically produces 180hp or less. That's just under 33hp/litre. My 1979 Austin Maxi was putting out around 58hp/litre! Anyone who takes off with a "near cold" engine deserves everything they get.

As I said in an earlier thread, I managed almost 1200 hours with a Rotax 447 two stroke, and didn't have it stop once. On two occasions I encountered a reduction in power, due to water in the premix fuel - it wasn't visible separately, but formed a waxy deposit in the filter. I also had a brief run of misfires, which eventually turned out to be a faulty ignition harness. This could have affected any petrol engine. I don't believe this otherwise good record was down to luck, but sensible engine handling and regular maintenance, which I carried out myself.

If I was constantly worrying about things going quiet, I would have packed in long before other circumstances intervened.

Shaggy Sheep Driver
16th Mar 2015, 22:09
Pram - here's some news for you. Every piston-engined aeroplane, especially air cooled ones, on its first flight of the day takes off with a near-cold engine. It takes a long time at high power for the entire engine, and its oil, to get up to even temperature throughout. You can't achieve that in ground running, especially with an air-cooled engine. Some bits will get very hot and will be under-cooled on the ground, while, other bits will stay relatively cold, so it's bad practice to ground run a cold engine for long periods.

This is why an aeroplane that is grounded for a long time should never be dragged out, engine run, then put away. If you start it up, fly it! If it can't be flown, don't start it up!

Get it into the air once the oil is hot enough, and get the whole engine warmed through without the very hot spots (heads, exhaust valves etc) getting too hot.

fdcg27
17th Mar 2015, 00:21
You list five things that can help to reduce the incidence of engine failure.
None of these things eliminate it.
Imagine flying at night or in acutal IMC or, better yet, night actual IMC in a single and hearing the sudden silence, despite your having done everything possible to maintain the engine and fuel supply system in good operating condition.
It happens, and your survival will depensd upon your having thought ahead of what your alternatives might be.
Nobody would like facing a forced landing at night or in bad weather, but the time may come when there isn't a choice.
You can reduce risk through proper maintenance, but you can't eliminate it.
When you rely upon the continued operation of the one powerplant to get you through a bad stretch, you're undertaking an additional risk.
The risk of engine failure can be reduced but not elminated.
The probability of a bad outcome following an engine failure can also be reduced, but only if we recognize the possibility and plan for it.
It's not a matter of if, it's a matter of when if you fly enough hours.

Chuck Ellsworth
17th Mar 2015, 00:39
It's not a matter of if, it's a matter of when if you fly enough hours.

Exactly:

How many here would fly only over the north Atlantic beyond gliding distance of land in a single engine anything?

In other words...every flight would be over water for your whole career.

Big Pistons Forever
17th Mar 2015, 00:51
The probability of a bad outcome following an engine failure can also be reduced, but only if we recognize the possibility and plan for it.
It's not a matter of if, it's a matter of when if you fly enough hours.

I totally agree with your statement, but this is a case of "what should be" vs "what is". What "should be" is that pilot induced engine failures are very rare, unfortunately "what is", is the fact that a very large percentage of engine failures reflect the lack of attention to piloting fundamentals.

I see a collective denial of this fact throughout GA and strongly believe the path to better outcomes is not practicing hero turn backs or perfecting your PFL flight paths, it has to start with a industry wide concentration on the importance of the 5 steps

However engine do fail despite the best efforts of the pilot and so risk mitigation procedures should always be applied.

For me that means the following.

For over water flight I try to stay in gliding distance of the shore and always wear a horse show type constant wear life jacket.

For night flight I will only fly multi engine aircraft at night, except that I will fly a single at night but only in the circuit.

Big Pistons Forever
17th Mar 2015, 00:54
To give a better idea of why extra speed is better than extra height immediately after take off here is a good example.

We were scooping water on a fire one day when I had an engine start to fail just after lift off from the water it happened just as I reached my start climb speed which was ten knots over the airplanes normal climb speed.

.

I am struggling to see how procedures appropriate to a 2 crew mutli engine flying boat with a disposable load have anything to do with EFATO's in SEP's

The extra speed gave me the inertia factor to allow me to scratch my nuts


Oh yah silly me I forgot the point of the post was to make sure nobody forgot about you skygodly powers. :rolleyes:

Chuck Ellsworth
17th Mar 2015, 01:26
I am struggling to see how procedures appropriate to a 2 crew mutli engine flying boat with a disposable load have anything to do with EFATO's in SEP's


It is directed at using speed in any airplane BPF.

This bit was meant to point out the extra speed means the inertia gave me more time to make a safe decision in how to react.

The extra speed gave me the inertia factor to allow me to scratch my nuts





Oh yah silly me I forgot the point of the post was to make sure nobody forgot about you skygodly powers.

You seem to have missed my point completely B.P.F.

And personal insults do not improve this discussion.

skyhighfallguy
17th Mar 2015, 03:15
IF you are flying at best glide speed in the majority of single engine light planes made by well known manufacturers, please tell me how there isn't enough speed to flare?

Best glide speed should give you the best (farthest) glide in a no wind situation.

And certainly there is enough energy to arrest the descent at the very end of the flight.

Excess speed might reduce the distance of the glide. AND while you may not need the distance, on the other hand you might.

We aren't talking about flying borate bombers, PBYs or anything else. Just little pipers and cessnas and whatever things the british have.

Chuck Ellsworth
17th Mar 2015, 03:41
We aren't talking about flying borate bombers, PBYs or anything else. Just little pipers and cessnas and whatever things the british have.

I am well aware that this is a private pilot forum, however private pilots are quite able to understand the laws of physics and aerodynamics and also understand these laws apply to all aircraft.

But if it it is creating a problem using aircraft other than little Pipers and Cessna's I can probably use them as examples so I don't irritate or confuse people like you Skyhigh.

O.K. ? :rolleyes:

skyhighfallguy
17th Mar 2015, 03:48
No response to the point I made about adequate energy to flare at normal best glide speed.

Chuck Ellsworth
17th Mar 2015, 03:57
No response to the point I made about adequate energy to flare at normal best glide speed.


Of course there is adequate energy to flare at normal best glide speed, I don't see anyone stating there isn't.

mary meagher
17th Mar 2015, 07:45
Now, now, boys, lets keep the party polite!

It is always entertaining for the rest of us mortals to see the pilot with the highest opinion of his own ability come unstuck.....

So let me lighten this thread with a story about an Engine Failure on Takeoff that completely satisfied all the witnesses.

For the first time EVER, the Chief Flying Instructor's wife agreed to come up with him in the motor glider, a Falke. (She felt safer in an aircraft with an engine!) The craft was preflighted. Taxied to the end of the gliding club runway, engine run up, and takeoff, towards the clubhouse, commenced. At a height of approx. ten feet the engine stopped.

(The equivalent for us as a cable break at low level) The Chief Instructor handled the power failure with superb technique and managed to stop before flying into the clubhouse. His wife climbed down and said she was never going up again, never!

The Chief Instructor was incandescent. "This airplane is unfit to fly! It will have to be grounded immediately until the Engineer has gone over this engine! Somebody could have been hurt!" etc etc etc.
Until another pilot, well experienced with the Falke, asked the question
"Did you check that the fuel was turned on?"

Silence.

Confirmation. The fuel was NOT turned on. (The custom had been that the fuel was normally left turned on...on this occasion a visitor had ended his flight by turning it off.)

The wife of the Chief Instructor, when sitting in the RH seat of the Falke, and being of somewhat ample proportion, made it impossible to verify the position of the fuel cutoff lever.....

I'm not sure whether a formal report was ever made, but we never let him forget it! No names, no pack drill.

9 lives
17th Mar 2015, 07:49
This bit was meant to point out the extra speed means the inertia gave me more time to make a safe decision in how to react.

When I've got a really important decision to make, I scratch my.... head. ;)

IF you are flying at best glide speed in the majority of single engine light planes made by well known manufacturers, please tell me how there isn't enough speed to flare?

Best glide speed should give you the best (farthest) glide in a no wind situation.

And certainly there is enough energy to arrest the descent at the very end of the flight.

Just to be precise, I've quoted the term "maximum" (rather than "best") from a selection of Cessna flight manuals to which I had referred. The intent being that gliding the plane at the speed for maximum glide will take you the farthest per altitude. That may be "best" if you need to make it to shore, but it may be far from the best, if there's a great landing spot right ahead of you, with some obstacles on the way, and a gusty wind. The pilot needs to make an informed decision as to what the "best" glide speed will be for each situation, and aim to be at that or a faster speed when an engine failure would be more critical.

So referring to:

The Cessna Flight Manuals I quickly reviewed (1979 C206, in particular) state a "Maximum" glide speed. It certainly won't be the best for an EFATO! If you attempt a flare and land from an EFATO at 50 feet, at the "maximum" glide speed in the flight manual of 65 knots, you're going to bend the plane. So, Cessna has wisely also provided a speed for EFATO; 80 knots. That's more like it.

A steady glide approach in a C 206 at gross weight at 65 knots will take you a long way (I've done it from 13,000 feet once), but if you enter a flare at that speed, things will happen very fast. So you are arresting a descent "fast", that means a more sudden change in approach angle, so more G, and trading speed for G more. If you get it wrong, there's nothing left at the bottom but a thump. When you look at the flight path, there will be a very small radius to the change from approach angle, to landing path. Small radius + bigger G = greater trade of energy. Or, from a faster glide approach, with a somewhat more steep angle, you have more stored energy, so that radius will be much larger, and the energy required to arrest the descent less, so you'll have less loss of speed, and more time to get it right.

This was taught to me during flying boat forced approach training, where a full stall landing, or worse, dropping it on, is very undesirable. My mentor told me to imagine I was going down a roller coaster, and at the bottom, smoothly pitch up as though to follow the rails - it worked perfectly. If you're a bit fast, just aim short of the intended landing place, and you have lots of control as you slow crossing the fence.

Though I do realize this it not the rotorheads forum, helicopter gliding none the less provides some insight to this. When gliding a helicopter, energy is stored as rotor RPM, up to 110%, more is better = longer to use it up flaring to land, so less rushed, better landing. But the maximum glide distance in a helicopter will be at a lower rotor RPM, because you're not storing energy in the rotor, you're only using it for the minimum lift you need to fly. If you flare from a low rotor RPM, things will happen really fast.

So, to a point, speed is your friend during any forced landing - speed = choice. Speed is easy to get rid of, when you no longer need it (you can slip a Cessna right onto the surface if you need to).

And it's worth remembering that if you really did get the speed wrong for your selected landing spot, you'd rather cross the near fence too fast, and not be able to stop for the far one, than to not make it over the near one, and crash into something at speed, without the opportunity to get the plane on the ground, and slow down for a while.

When it suddenly goes quiet, decisions must be made with little head scratching - 'cause your thinking, planning skill and experience have covered most of the factors.

Big Pistons Forever
17th Mar 2015, 12:15
And it's worth remembering that if you really did get the speed wrong for your selected landing spot, you'd rather cross the near fence too fast, and not be able to stop for the far one, than to not make it over the near one, and crash into something at speed, without the opportunity to get the plane on the ground, and slow down for a while.

.

This is IMO an extremely important point and is the reason why it will always be better to chose the crappy field that is close rather than try to stretch the glide to try to make the "nice" field.

When it suddenly goes quiet, decisions must be made with little head scratching - 'cause your thinking, planning skill and experience have covered most of the factors

The challenge for new pilots is they won't have the experience part of the "thinking,planning skill and experience" trifecta. So for those pilots having a plan is vital as the lack of experience makes it harder to react to a fast developing situation by using the knowledge gained from seeing similar events in the past.

Sam Rutherford
22nd Mar 2015, 08:59
Is maths allowed?

Number of GA departures / number of GA EFATO? (you can pick your timescale "per day/month/year")

I suspect the result is an extremely small number.

Not zero, but...


Then, another sum:

Number of GA PFL / number of GA PFL that end up going wrong and end up on the ground

Also a very small number, but just might be higher than the first answer.

Just a thought...

Gertrude the Wombat
22nd Mar 2015, 10:30
Somebody did do those sums wrt spinning at least, which is why it's no longer in the syllabus.

Rod1
22nd Mar 2015, 15:31
After my first engine failure back in the 90's I did an analysis of 6 or 7 years worth of engine failure data. About 50% were no significant damage or injury, about 25% was no significant injury but significant damage to the aircraft. The remaining 25% were significant injury or death plus serious damage. I regularly do PFL's and do not think I would be around to debate on the forum if I had not.

Rod1

Big Pistons Forever
22nd Mar 2015, 19:06
A lot of the posts on this thread seem imply that I am advocating ignoring the requirement to be proficient in handling a PFL. If that message came across from what I have written than it was not my intent.

Instead I would like to re-emphasize that I believe dealing with an engine failure starts with taking objective measures to minimize the risk of the engine failing in the first place, as actions or inactions of the pilot is cause of the majority of engine failures.

Following that is thinking of and practicing the vital actions drills that will restore power, if practicable and obviously not applicable to a EFATO, and then yes practicing the power off glide path judgement that is obviously vital to a successful arrival after an engine failure. Of note you don't have to do a PFL to do that, simply when traffic and local airport procedures allows, make your landings start with closing the throttle at various points in the circuit.

Finally a safe pilot has to be proficient at every part of flying, not just doing PFL's. The accident record clearly shows that the majority of bent metal are landing and takeoff accidents that are a result of a lack of skill on the part of the pilot.

I think the whole engine failure thing feeds the secret hero pilot fantasy lurking in almost everyone. "There I was minding my own business when BAMM the engine blew up. But I did not panic and side slipped the little sucker into that postage stamp field rolling to a stop with no damage to the airplane ! "

The "my vigilance at doing a comprehensive pre flight check caught the build up of carb ice as I was waiting to takeoff and thus prevented the EFATO" is a lot less sexy, but ultimately represents a narrative just as important, if not more important, as the first one....

thing
22nd Mar 2015, 19:21
Number of GA PFL / number of GA PFL that end up going wrong and end up on the ground

Also a very small number, but just might be higher than the first answer.
Reminds me of the Meteor asymetric handling exercises in the 50's; they killed more pilots than actual engine failures. Here's an interesting stat that makes you think about how our attitudes to safety have changed. The RAF lost some 850 (yup, that's 850) Meteors with the loss of around 370 pilots.

9 lives
22nd Mar 2015, 19:48
But I did not panic and side slipped the little sucker into that postage stamp field rolling to a stop with no damage to the airplane !

Haha, I've pulled that off three times, I think I've used up my "nine lives" on those!

The skills to prevent unplanned events are of great importance, but they are not the same skills as those applied to dealing with them. Yes, if I'd poured alcohol into the fuel tanks, two of those glides probably would not have had to be flown so adequately. Preparation skills are intellectual, and largely ground training. Dealing with the sudden silence is muscle memory stuff....

So, the probability of an EFATO goes way up with poor preparation for the flight. But, the EFATO has to be one of the most challenging events to demand judgement and skill instantly, and all the way to the ground. It's worth the regular practice. Luckily, I fly mostly at very quiet airports, so PFL's from the circuit are common for me. Those times I have to sneak in some power on the base to final turn, tell me that I'm not practicing enough!

A few years back, I had to fly a few maintenance check flights on a Tiger Moth, which had not flown in a decade. I flew the entire circuit as an impending EFATO - because honestly, I have never glided a Tiger Moth, and did not have the muscle memory to handle it well!

When I'm training pilots, I'm one of those annoying mentors who first says to fly a more close in downwind, and then at the right point I'll say "you can make it to the runway" as I gently pull the power to idle.

squidie
22nd Mar 2015, 20:48
All those are of which part of the pre-flight checks.

9 lives
23rd Mar 2015, 08:53
Most engine failure causes can be at least mitigated by effective preflight checks, and pilot behaviour. So, yes, good preflights, and pre takeoff techniques.

However, I have had one total failure, and two major power losses, whose causes were entirely mechanical (not poor maintenance) related. So, patting yourself on the back for an awesome preflight, and operating technique to the "position and hold" point, should not cause you to relax your guard for an EFATO,

Two causal factors I have had: Stuck exhaust valve just after liftoff. The engine does not stop, but you sure think it's going to, while you struggle to climb out at less than 75% power. And, a mouse nest of fibreglass insulation from under the instrument panel, being sucked up a hot air hose into the carburettor venturi. That one put me into the field off the end of my runway!

Jetblu
23rd Mar 2015, 20:00
Statistics suggest that all the best pre flight inspections in the world will not significantly reduce EFATO as they are all generally mechanically based.

I've had two piston engine failures. First reason was broken piston ring that smashed up the engine. Second reason unknown cause as I had to ditch in the Channel.Suspect a hole through side of the engine as oil was smelt.

Chuck Ellsworth
23rd Mar 2015, 21:01
Statistics suggest that all the best pre flight inspections in the world will not significantly reduce EFATO as they are all generally mechanically based.

Not according to one of the flight instructors here who claims 8 out of 10 are pilot caused.

9 lives
23rd Mar 2015, 21:13
Chuck... That instructor has a point... Actually, 10 out of 10 EFATO's are pilot caused - 'cause they would not happen if pilots were not trying to do point things with planes! ;)

Rod1
23rd Mar 2015, 21:20
Having asked around locally, most of us who have had engine failure had mechanically based issues or fuel. Mechanical issues included crank failure, mag failure, prop disintegrating after stone damage on takeoff, bird through canopy, oil pipe fail covering canopy with oil. Fuel was all around vapor lock or blockage in the system, one pipe / valve split. I am a big fan of know your aircraft and check it before flight (I built mine;)), but I am not convinced that many of the above could have been spotted on the ground by an average PPL with normal piloting kit.

crank failure - no chance
mag failure - no chance
prop disintegrating after stone damage on takeoff - no chance
bird through canopy - no chance
oil pipe fail covering canopy with oil - probably no chance
vapor lock - probably yes - know your aircraft
Fuel blockage - No chance
Fuel pipe / valve split - probably not

Rod1

Chuck Ellsworth
23rd Mar 2015, 21:34
These discussions tend to drift all over the place Step Turn.

There are a few mistakes that pilots make before take off that can cause the engine to fail right after take off.

Failure to select a tank with fuel in it.

Carb ice

Water in the fuel.

The other killer is taking off with control locks on / engaged.

These discussions are interesting and there are a lot of things that are useful to remember, however flying light single engine airplanes safely is well within the ability of the average person in our society.

Sometimes over thinking these things is just as bad as not thinking.

Big Pistons Forever
23rd Mar 2015, 22:49
Chuck... That instructor has a point... Actually, 10 out of 10 EFATO's are pilot caused - 'cause they would not happen if pilots were not trying to do point things with planes! ;)

The sole purpose of this post seems to be to heap ridicule on the premise of my my thread. I find that rather disappointing...

Big Pistons Forever
23rd Mar 2015, 23:11
Statistics suggest that all the best pre flight inspections in the world will not significantly reduce EFATO as they are all generally mechanically based.


I think if you ask most GA pilots their opinion on this matter, that is the answer you get. Certainly that is what is generally being taught in flight schools.

Unfortunately it is simply not true. If you do not believe me just go and review the last 5 years worth of AAIB or NTSB accident summaries. If you do that you will find lots of fuel exhaustion/fuel mismangement/fuel contamination/engine mismangement/carb ice caused accidents but not very many where the engine failed due to a mechanical failure of the engine itself or an engine accessory. And even those often involved flying an engine with a known fault.

I will add a caveat. As I mentioned earlier I am talking about simple Lycoming or Continental engines, or the engines I believe most of the readers of this forum are flying behind. Older 2 stroke microlight engines and some of the weirder car engine conversions ( not the good VW conversions) as well as various pre WW 2 early aero engine designs have a horrendous record of inflight failures due to mechanical failures and so obviously the 80 % pilot caused number does not apply to those.

Personally I think it is much more palatable to us pilots to believe the myth that most forced approaches are the result of a mechanical failure that the pilot could not reasonably have foreseen. It is a lot more uncomfortable to think about the fact that a lot of airplanes are needlessly wrecked because the pilot failed to adequately pay attention to the basics, like making sure there was enough uncontaminated fuel with the fuel selector correctly set, or not allowing carburetor ice to develop to such an extent that the engine stopped.

The first step in reducing the number of crashed aircraft is to understand where the problem is, and it is not perfectly good engines suddenly stopping because of mechanical failures. Unfortunately that is almost always the starting point of the discussion, training, and practicing of the engine failure scenario.

If one person reads this and realizes that maybe they were a little lax on some of the cockpit good house keeping and makes a permanent change in how they are operating their aircraft, I will be happy as there will be at least one pilot who will be less likely to cause an aircraft to be needlessly bent.

Big Pistons Forever
23rd Mar 2015, 23:23
Having asked around locally, most of us who have had engine failure had mechanically based issues or fuel. Mechanical issues included crank failure, mag failure, prop disintegrating after stone damage on takeoff, bird through canopy, oil pipe fail covering canopy with oil. Fuel was all around vapor lock or blockage in the system, one pipe / valve split. I am a big fan of know your aircraft and check it before flight (I built mine;)), but I am not convinced that many of the above could have been spotted on the ground by an average PPL with normal piloting kit.

crank failure - no chance
mag failure - no chance
prop disintegrating after stone damage on takeoff - no chance
bird through canopy - no chance
oil pipe fail covering canopy with oil - probably no chance
vapor lock - probably yes - know your aircraft
Fuel blockage - No chance
Fuel pipe / valve split - probably not

Rod1

My experience has been different. In the last 20 years there have been 7 in flight engine failures that occurred on aircraft based at my home airport.

2 fuel exhaustion ( C 150 , C 172)
2 mis managed fuel selector ( Pa 28 C 172)
2 Carb ice ( C 150, Aeronca Champ)
1 Catastrophic engine failure after a connecting rod broke ( C 172)

As should be rather obvious as a pilot and flying instructor I am very interested in the engine failure scenario in light aircraft.

I would appreciate some more detail on the incidents you described.

Specifically

-Mag failure. Was this a dual simultaneous failure ?
- Prop disintegrating after stone damage. Was the prop damaged prior to the takeoff or did it hit a rock on the takeoff roll ?
- Bird through the canopy. How did this cause the engine to fail ?

9 lives
24th Mar 2015, 05:38
The sole purpose of this post seems to be to heap ridicule on the premise of my my thread.

My apologies, very certainly not, 'just joking Chuck, that's all. I must have missed an inference. Attempt at humour humbly withdrawn....

Rod1
24th Mar 2015, 09:53
-Mag failure. Was this a dual simultaneous failure ?
- Prop disintegrating after stone damage. Was the prop damaged prior to the takeoff or did it hit a rock on the takeoff roll ?
- Bird through the canopy. How did this cause the engine to fail ?

Not all mine so details only on some;

Mag failure Robin DR400 C of A aircraft 160hp Lyk

I noticed an increase in fuel consumption 9 months before the incident. Maintenance organization checked everything NFF sent me the bill. I persisted - they sent the carb off to be checked, NFF. Real problem was poorly mag wiring which was breaking down when hot. Good Mag failed leaving me with a very unhappy engine and a lot of vibration. Landed with no damage

"Prop disintegrating after stone damage. Was the prop damaged prior to the takeoff or did it hit a rock on the takeoff roll ?"

Not mine but I understand there was a bang just as he got airborne off a short strip. All normal for about 20 sec then the prop tip came off. Damage from stone obvious on later inspection. Pilot had to shut off all power due to huge vibration. Landed without incident.

"Bird through the canopy. How did this cause the engine to fail ? "

No further info. Aircraft overturned in soft ground but at relatively slow speed. (again not one of mine).

This is from a group of experienced pilot owners which may be relevant?

Rod1

Big Pistons Forever
24th Mar 2015, 16:28
-Mag failure. Was this a dual simultaneous failure ?
- Prop disintegrating after stone damage. Was the prop damaged prior to the takeoff or did it hit a rock on the takeoff roll ?
- Bird through the canopy. How did this cause the engine to fail ?

Not all mine so details only on some;

Mag failure Robin DR400 C of A aircraft 160hp Lyk

I noticed an increase in fuel consumption 9 months before the incident. Maintenance organization checked everything NFF sent me the bill. I persisted - they sent the carb off to be checked, NFF. Real problem was poorly mag wiring which was breaking down when hot. Good Mag failed leaving me with a very unhappy engine and a lot of vibration. Landed with no damage

"Prop disintegrating after stone damage. Was the prop damaged prior to the takeoff or did it hit a rock on the takeoff roll ?"

Not mine but I understand there was a bang just as he got airborne off a short strip. All normal for about 20 sec then the prop tip came off. Damage from stone obvious on later inspection. Pilot had to shut off all power due to huge vibration. Landed without incident.


Rod1

I had a partial engine failure similar to yours. It was in cruise flight and all of a sudden the engine started running horribly with high vibration and a great loss of power. As I had the time I methodically troubleshot the problem. Changing tanks and adjusting throttle/mixture/carb heat had no effect so I tried switching to one mag. As soon as I switched to the left mag the engine sudden ran smoothly and power picked right up.

After an uneventful return to my home airport the problem was diagnosed as an internal failure of a mag gear. This caused the spark on that mag to advance 20 deg:uhoh:. The engine did not at all like the dueling mags and therefore ran like shyte. However switching to one mag instantly restored what was effectively full power. I raise this because it is an inflight troubleshooting trick that does not seem to be often covered in flight training.

Obviously In my case I was in cruise so I had lots of time to methodically troubleshoot. You don't want to faffing around switching mags in the EFATO scenario, just concentrate on flying the aircraft to a safe arrival.

With respect to the prop. I don't want to sound rude here, and obviously I am looking at this at 3 rd hand distance, but frankly I am a bit skeptical that a perfectly sound prop hits a rock and flies apart. I suspect that the prop already had a few big dings in it and the rock was the final straw.

Anyway the the bottom line is the importance of a good preflight check of the prop and getting any dings immediately dressed out before they could affect the structural integrity of the prop.

gasax
24th Mar 2015, 16:33
I tend to BPF's view, engines usually try and tell you they are not happy, even when something occurs during a flight a partial power loss, albeit sometimes a considerable level are the most common effects.

I've had three serious engine problems in just under 30 years, all of them the engine kept running - although in one case very unhappily.

Emeraude - fuel pump failure, fuel would reach the engine whenever the nose was lowered - at least it gave me some options!
Terrier - cylinder head cracked, engine would run at 1700 rpm max, very lumpy but made me quite a good glider!
Terrier - cylinder crack, 1700 rpm again...

Equally at our airfield I've seen people 'flight test' engines with issues and then get very sweaty when the faults were still present!