Exactly.
When I once had a ride as a backseat passenger in a C210 departing Dusseldorf we experienced a “cracked” magneto one minute after take-off at 1000ft GND. The engine was running very rough as the bad magneto was still firing.The pilot immediately turned back to the departure runway, switched tanks and radioed to ATC who had to stop other traffic.
We glided back successfully with more or less idle power. On the ground we then diagnosed the magneto problem. With all that workload it would have been very cool had he detected the cause of roughness while still in flight. Since then I try to include that in my scan should any roughness occur. As I remember flight schools teach a magneto failure as a “dead” magneto which is not always what happens in real life.
It seems the truth is that many pilots wouldn’t have the idea to cycle the mags when engine roughness occurs.
Isn’t this standard for PFL checks?
Peter’s reducing power when checking the mags is good advice – the risk of an interesting backfire could incinerate your exhaust.
I had platinum contacts failure over the Alps three weeks ago after departing from EDNY. Engine lost some power and EGT on all cylinders rose. I didn’t know what exact failure it was but I was clear that one magneto wasn’t firing. Before take-off engine check was ok, both magnetos were ok. After landing I repeated the check (low RPM, below 1000) and on the LEFT position there was no drop while on RIGHT position engine was shutting down.
Very few people know about that. I didn’t know about it till maybe a year ago (even though it is obvious).
But also you need balls of solid steel to start messing with the ignition switch, when the engine is running rough and you are nowhere near an airport.
Also you have to know that if you turn off a mag in flight, you have to be ready to close the throttle if the engine sounds not perfect, and switch back to BOTH before re-opening the throttle. Or you might blow the exhaust system. This is the “in-flight LOP test” under another name.
Why not turn off one magneto
Always an interesting point, Achim. Both magnetos and spark plugs can play havoc with the engine and cause roughness. Switching one of the magnetos off can indeed cure the problem.
It seems the truth is that many pilots wouldn’t have the idea to cycle the mags when engine roughness occurs. Sadly, many POHs don’t mention this in the checklists (some don’t even have an “engine rough” checklist, only engine failure, which happens much more rarely).
The concept also isn’t always taught well by instructors.
Obviously there’s selection bias
You will get a lot of that. There was an [in]famous survey done in the PA46 community and something like 10% of them reported an in-flight engine shutdown. Not just a failure with which they could fly on but something which needed a landing ASAP (which BTW is what I would classify as an engine failure). But obviously a lot of people without problems would not have responded, not least because it is the people who are getting a bit concerned over something that seek out online communities where they can discuss it.
I don’t think engine problems like Achim reports are very common. I have done 1400 hrs airborne on my engine, without a slightest issue. If it was a turbo engine (TIO-540) then I would prob90 not have got to 1400hrs without cylinders changed, which I suppose is still not an “engine failure” but if you get a bad cylinder crack the cylinder might come right off.
A friend of mine had a cracked Champion spark plug in his new SR22G3 & had to limp back to the nearest airfield with strong engine vibrations & greatly reduced power.
Why not turn off one magneto? We have two ignition systems for situations like that. Hardly an “engine failure”.
Would anyone classify denopa’s engine episode over the Albanian Alps in the Trips & Airports section as an ‘engine failure’? Or even a “partial” failure?
No, it was partical loss of power but nothing more. He didn’t even declare an emergency and it was not an emergency landing because he was able to control the point and time of the landing (he even considered a go-around). Clogged injector nozzles are a very common problem.
I had a stuck exhaust valve in flight over Africa, even that wasn’t an “engine failure”.
engine issues resulting in grave concerns of the continuance of safe flight seems to be much more prevalent than once every 50,000 hrs.
Sure but the engines are designed so that very few of those lead to catastrophic failures (i.e. engine stoppage).
So Peter’s 50k figure is at least at the correct order of magnitude.
There was an interesting discussion on the Cirrus pilot’s website a while ago, with an informal survey based purely on anecdotal experiences: “Have >you< ever experienced an engine failure”?
Pretty much every pilot with > 7-10,000 hrs of flying experience answered in the affirmative. Obviously there’s selection bias etc & the experience was gained over many years on all sorts of equipment etc.
However, I did myself experience a partial engine failure as a passenger on a Gyrocopter a while ago (the Rotax 912 blew a cylinder) at 450hrs TT, requiring an off-airfield precautionary landing.
One of the guys over at the Cirrus website picked up his brand new SR20 at the factory a couple of months ago & apparently the Continental failed on take-off for the flight home, requiring the installation of a completely new engine.
A friend of mine had a cracked Champion spark plug in his new SR22G3 & had to limp back to the nearest airfield with strong engine vibrations & greatly reduced power.
Neither of those incidents figure anywhere in the statistics.
I reckon those engine manufacturer reliability statistics have a fairly specific definition of engine failure. While 50,000hrs may be technically correct, engine issues resulting in grave concerns of the continuance of safe flight seems to be much more prevalent than once every 50,000 hrs.
Just curious: Would anyone classify denopa’s engine episode over the Albanian Alps in the Trips & Airports section as an ‘engine failure’? Or even a “partial” failure?
With the possibility of the one drive shaft failing on these dual mags and thus making both inoperative, I would think that some form of separate electronic ignition system would make sense. I’m not sure how it could be implemented on a TC aircraft but I have seen it on LAA (Permit) types.
