Dealing with engine failure in single engine aircraft is one of those things we practice in training, check rides, and BFRs. Engines fail for a lot of reasons. Mechanical problems, operator error, fuel issues, and ice have all been the root cause of aircraft accidents. The NTSB aviation accident data base only has data on the bad outcomes of losing an engine. That means it understates the 'real' number of piston engine failures in single engine aircraft. Whether the NTSB data is 'off' by a little or a lot is unknown. Could the relatively small number engine failure accidents in the NTSB data base perpetuate a myth of engine reliability? Do most pilots who lose power in a Fixed Wing, Single Engine, Factory Built aircraft avoid bending metal because of skill, luck, or both?

Based on my own experience, and that of pilots who have responded to this survey elsewhere it looks like the NTSB accident data isn't a good estimate of the number of power loss events experienced by pilots. Respondents to date report that only about 1 in 5 pilots who lost all power (for ANY reason) experienced an NTSB reportable accident. Partial power loss seems to result in even fewer NTSB reported accidents.

Would you invest just 5 minutes and share your own experience by completing this survey? Sharing your experience with piston engine reliability will help us all better prepare, and perhaps reduce the number of engine failures that ever become accidents.

https://www.surveymonkey.com/r/NF92626

Please complete the survey even if you've never experienced the sounds of silence from your piston engine.

The survey has just six questions. I ask about your overall flight experience, then focuses on your experience in Factory Built, Single Engine, Fixed Wing, Piston Powered aircraft... like the Cessnas, Maules, and Pipers, etc. that most of us fly. However, I also ask about your experience in other airframes (EAB, helicopter, glider, jets, ME piston, turbines, balloons) since this is a good indication of proficiency and overall experience.

Please take just five minutes and share your flying experiences. Please respond to the survey, regardless of whether you have ever dealt with a complete or partial engine failure.

Using data you provide I will estimate the ratio between the frequency of engine failures we have collectively experienced, and explore how often a piston engine failure might result in an accidents or incident. I will also use data from the survey in FAASTeam safety seminars and webinars, SAR training, and in articles.

Again, even if you have never, ever experienced an engine failure please participate in the survey. It’s important that the data set include the experience of pilots who have NEVER lost their engine, as well as from pilots who have had multiple "opportunities" to demonstrate proficiency with emergency procedures.

FWIW, the National Transportation Safety Board reports that in 2012 loss of power was the second highest cause of accidents. Take a look at the part 91 graphic in the 2012 report titled "Defining Event for Personal Flying Accidents" posted under Data and Stats on the National Transportation Safety Board website at http://www.ntsb.gov/investigations/d...20Summary.aspx

Done. Great idea.

I’ve had 3 total engine failures in singles. (others in twins). Two of the three were factory engines, both gave warning signs and/or "should have knowns”. Older planes, back when......


Looking forward to results.

Nice survey. Short and easy to complete. Great job putting it together.

. " Again, even if you have never, ever experienced an engine failure please participate in the survey. "

That's me. Had a partial failure once during run up, but just taxied back. I suppose uneventful is a good thing.

I have always rented, and never owned. Not sure whether that is something that enters into the equation re maintenance.

If Contact gets on here it's gonna skew your data.

I imagine professionally maintained/fleet types vs. amateur maintained (me) might pull the data around.

Bill

Just a heads up.

When I filled out my flight times, it didn't like any commas in the number entries. Kicked it back saying "Please enter a positive number."

Removed the commas and it took it.

Done.

Cary

CFOT,

I took the survey. Yes, if everyone doesn't do it, it could look bad. I always come up with 12, but later remember one more. I regret losing so many engines, running so many airplanes out of gas, and tearing up two or three. It was interesting and informative, however. There are better ways to fly. None cheaper than flying junk. The total of my losses was $37,500, excepting Uncle Sam's Cobra.

Contact

I have about 1,650 hours and never had a problem other than carb ice or fouled plugs and a cracked cylinder head (found on runup) but I do not think airplane piston engines are especially reliable.

They may not FAIL often but they act up plenty.

A guy can go to the Kia dealership and buy the cheapest econobox on the lot and drive it 200,000-300,000 miles and never have a problem. Certainly no carb ice, broken magnetos, or fouled plugs or cracked jugs. Yes I know it's not an apples to apples comparison but I think we give our engines more credit for relaiablity than they deserve.

I also think that if we were afforded modern technology our engines would be less expensive, higher performing, and more reliable.

But, it is what it is. Especially as it applies to certificated aircraft. It's pay up and shut up, or get off the bus.

I have given the FAA a hard time about not thinking through its instrument orientation and altitude maintenance at all costs indoctrination, but I think they have done admirably with aircraft design standards and engine standards.

My many engine failures were all my fault and/or the fault of the operator and/or mechanic. What makes aircraft parts,including engines, so reliable is how carefully work is documented and problems are tracked and eventually fixed. Auto engine design and maintenance is not tracked and fixed as quickly and efficiently. Their lawyers are looking at percentages over hundreds of thousands iterations. The Airworthiness Directive system is concerned with just a few iterations.

I am not very knowledgeable about providers of experimental engines and parts, but one of my engine failures and a lot of problems with another car engine made me leery. A provider and engineer of airplane ready Subaru engines proudly claimed that all the problems they had with their single ignition system occurred in the first ten hours. He kept repeating that the engine was bulletproof. I was fairly sure he had never been shot at.

After they sent three different free props and kept having us shorten them, I realized we were doing the test flights for their R&D. They finally sent a free greater reduction system so we could get the RPM up to 6,000.

The hard part here is definitions. Define engine, define failure, and define the relevant causes.

I know a bunch of pilots who would say they had an "engine failure" in flight. But their engine didn't fail them, they failed. What they mean is, they didn't fuel it up before they left, or they didn't remember to switch tanks, or they didn't use carb heat when required, and the list goes on.

It's more often pilot error than mechanical failure. I've only seen a few engines which actually cracked a cylinder and lost power. Of course it does happen and I've seen it a number of times.

But people who report "I've had 3 engine failures in my XX,000 hours flight experience" - often they mean they've stuffed up three times.

Agreed!

master rod bearing failure, 3350....

crankshaft breaking, 0-320


bilateral coil failure, Franklin 165....


nope, I think all 3 of those were real “failures”.


Of course, in the turbine world they have “uncommanded power rollbacks”, which they don’t count as failures....but the engine quits producing power anyway...

My one total engine failure was very definitely a real failure--threw a rod through the top of the case, necessitating an immediate landing in a field.

My other temporary engine failure was caused by impact icing which closed off the air intake of the Mooney 231 and caused us to lose 1300' before ol' Dummy here remembered to pull the alternate air door knob.

As the saying goes, flying is hundreds of hours of boredom punctuated by a few moments of sheer terror. Been there, done that! I much prefer the boredom.

Cary

Battson wrote:The hard part here is definitions. Define engine, define failure, and define the relevant causes.

...It's more often pilot error than mechanical failure.

That's true. Sometimes the cause is pretty obvious, a lot of times not so obvious until tear down. Some powerplant "failures", maybe a lot of them, happen because the pilot abuses the engine. In any case the NTSB data pretty clearly shows that 'powerplant malfunction' is second only to loss of control as the 'defining event' for US accidents. That's been the NTSB's finding for several years now.

Regardless, if the powerplant stops producing rated power (or quits completely) the outcome is the same. The plane will return to earth sooner (if the engine quits) and a bit later if it still produces a little power. In every instance we still have to fly the plane and respond to the emergency.

After over 500 responses to the survey the numbers are pretty consistent. Around 1 in 5 instances when the powerplant croaks result in an accident. Another 1 in 6 result in an FAA 'incident'... i.e. the damage and injury don't reach the standards in the NTSB 830 reg.

Very few of these engine failures involve fuel exhaustion. A few complete and partial failures resulted from fuel STARVATION... i.e. fuel pump malfunction; crimped fuel line; etc. The vast majority involved some mechanical issue (swallowed a valve, cylinder came apart, mag failed, camshaft broke, carb ice/impact ice killed the engine, etc., or some part was replaced with wrong item, or something didn't get assembled correctly after maintenance). Several respondents said their engine was recently in maintenance. In some cases the offending parts were in place for 10's or even a hundred hours or two... then failed.

In case you've not responded to the survey, here's the URL: https://www.surveymonkey.com/r/NF92626 If you've already shared your experiences, thanks.

FWIW, "engine", "failure", and "causes" are clearly defined in the survey. Also, to have a manageable, and comparable data set I've asked for engine failure data (resulting from ANY cause) for just Single Engine, Factory Built (i.e. on a production line like Cessna, Piper, Maule, etc.-- Not EAB), Piston Engine, Fixed Wing aircraft. While I'd like to know your experience flying different airframes, please don't include engine failures in your helicopter, turbine engine, jet engine, rocket engine, etc. power aircraft. Also, please don't include engine failures you've experienced with piston engines that were hung on a multi-engine airframe.

Done.

The only issues I've had relate to pilot-induced intake or fuel management. Aborted T/O in a 172N because of a power dip on the roll which was my fault, but I stopped anyway just to be sure (counted as '0' in the survey because I technically never left the airport). I've also been a pax in a 310 when someone flipped a fuel selector the wrong way and made one side pretty quiet for a minute. And the occasional carb ice, though that's a rare problem here in CO where the air is so dry.

Barring outright manufacturer defect of parts, based on my informal reading of other pilots' experiences it seems like these engines generally run a very long time *provided you manage them appropriately*. Over-temp on the parts is an engine killer, and some people just suck at keeping things in the right temp range. Shock cooling can be a bad thing as well, though you have to try a fair bit harder to accomplish that. Proper periodic maintenance is also absolutely critical. Being smooth on the power and not abusing the thing tends to lead to many cases of engines going well past TBO with nary a glitch in flight.

I don't think the Kia comparison is generally fair either. The car will run 200k miles sure, but how much of that is at maximum horsepower near redline? My guess is a few percent at most. Our engines run in that regime almost all of their life across wide ambient temperature margins, and without the benefits of water cooling. Also if you figure 130kts cruise, 2000 hours is nearly 300k statute miles of distance flown. Of course we need to decrease that for time around an airport but still, say 250k miles for comparison? That's pretty good. You *will* replace something on that Kia motor in that time - alternators, radiators, injectors, these parts just wear out.

Do we accept higher risk in an airplane? Of course - you can't just pull over when something bad happens. Do I have qualms about putting my family in a well-maintained, regularly flown aircraft over the remote chance of a catastrophic engine failure? With proper risk management, not really.

Thanks copilot. While I agree with your observations about maintenance, excess heat, and shock cooling survey responses suggest a lot of powerplant malfunctions occur, far more than show up in the NTSB data base. FWIW, in 2013 "powerplant malfunction" was the number one cause of GA personal flying accidents - most of which was SE piston aircraft. Add in fuel issues (some pilot caused, some from neglect, some just 'cause') and a few of the 'unknowns' and the number of engine issues gets pretty impressive.

I'm still collecting data, and the survey is still running with 535 respondents. Current gross statistics are:
Total time in all powered aircraft: Average 2700
Total time in Piston SE FB acft: Average 1560
Number of partial power loss events: 208
Number of partial power losses with NTSB Accident: 9
Number of partial power losses with FAA Incident: 6
Number of complete power loss events: 136
Number of complete power losses with NTSB Accident: 28
Number of complete power losses with FAA Incident: 15

FWIW, the average flight hours are fairly stable within a range of 60 hours +/- or so. The ratio of accidents/incidents to partial power loss events is very stable. For example, about 1 in 20 partial power loss events results in an accident, while about 1 in 5 total power loss events results in an accident.

If anyone else who's not yet responded to the survey would like to offer their experience your data will strengthen the data base. Your experience is very important, regardless if you NEVER EVER had any power loss events, or you've experienced lotsa engine issues that required an off airport or 'other' airport landing.

The caveats are as follows. Your experienced engine issue OR lack of an engine issue (partial or complete power loss from any cause) must meet all five of the following criteria :

1. Piston engine
2. Single engine
3. Fixed wing
4. The aircraft must be 'factory built' (i.e. NOT a homebuilt), for example Cessna, Cirrus, Beech, Mooney, etc.
5. Because of a power loss problem you either made an off airport landing, or landed at an airport that was not your intended destination... i.e. made a precautionary or forced landing. For the purposes of this survey if you were on your takeoff roll and aborted because your engine quit/had and unexplained loss of power that would count.

Here's the link to the survey: https://www.surveymonkey.com/r/NF92626

Thanks!

PapernScissors wrote:Thanks copilot. While I agree with your observations about maintenance, excess heat, and shock cooling survey responses suggest a lot of powerplant malfunctions occur, far more than show up in the NTSB data base. FWIW, in 2013 "powerplant malfunction" was the number one cause of GA personal flying accidents - most of which was SE piston aircraft. Add in fuel issues (some pilot caused, some from neglect, some just 'cause') and a few of the 'unknowns' and the number of engine issues gets pretty impressive.

Well, this is where the data dispels the anecdotal BS, so I like numbers too. I also wonder if the prevalence of failure has anything to do with use of the engine, but that's a hard area to study accurately.

If you haven't done it already and I'm just not seeing it, would you mind if I cross post this thread (and your survey) to some other aviation forums (Cessna Pilot Assoc., Cessna Pilot Society, AOPA) to get a better sampling of pilots for your data? In this case more is better.

Is it possible to compare privately owned single engine piston with commercial single engine piston?
To see if the extra requirements pay off?

I say this because in Costa Rica every piston engine airplane is required a 50 hr , 100hr inspection plus annual inspection.
Owners are not allowed to work on their planes.
I never complained about this.

In 7 years flying there and seeing airplanes fly, there has been only 1 single engine failure, and was a Pitts who took off and inverted the plane immediately started sputtering, he crash landed and survived.


Plane has not been flown in 3 years before that flight.

But I think its a pretty good record (I know its a lot less flights than in the USA but still not bad).

So wondering if we can compare commercial piston vs private piston reliability record.

colopilot wrote:If you haven't done it already and I'm just not seeing it, would you mind if I cross post this thread (and your survey) to some other aviation forums (Cessna Pilot Assoc., Cessna Pilot Society, AOPA) to get a better sampling of pilots for your data? In this case more is better.

The survey has been on about five forums, including BCP and AOPA. Pls do put it out on CPA and CPS.

Data is our friend. As the survey has progressed I've shared preliminary results with CFI friends. Many were very surprised at the number of power loss events (from all causes) that don't show up as 'accidents'.

The survey asks for power loss from ALL causes. When the chips are down it doesn't matter if it's fuel starvation, fuel exhaustion, severe carb ice, or a busted crank, a swallowed valve, whatever. The fundamental problem is the same: Our 1st and only priority is land in a survivable location with minimum injuries and loss of life. If the plane is intact when it's all over that's fine, but not a priority or objective..