Signs to recognize an engine failure asap

RyanB

RyanB

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This may be a dumb question but it never hurts to ask. How do you know if you really have an engine out or start to lose power? Say your taking off (or even at altitude) about 500ft agl and you have a failure, what are signs you will notice that are out of the ordinary? Obviously the engine sound will change and you may feel deceleration but as far as engine sound goes, i assume it will be noticeable. We get accustomed to how everything normally goes so if something were to develop i feel like its important to know what is actually happening ASAP and do something instead of "something doesnt seem right, but im not sure if its actually happening" and not your mind playing tricks on you if that makes sense.
 
Ryanb said:
This may be a dumb question but it never hurts to ask. How do you know if you really have an engine out or start to lose power? Say your taking off (or even at altitude) about 500ft agl and you have a failure, what are signs you will notice that are out of the ordinary? Obviously the engine sound will change and you may feel deceleration but as far as engine sound goes, i assume it will be noticeable. We get accustomed to how everything normally goes so if something were to develop i feel like its important to know what is actually happening ASAP and do something instead of "something doesnt seem right, but im not sure if its actually happening" and not your mind playing tricks on you if that makes sense.
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High oil Temperature, low oil pressure and high CHT are good indicators.
 
If your losing lots of power, At five hundred feet no time to analyze......simply look for a field and go for it more or less straight ahead.
 
Manifold pressure loss and RPM loss will be present in varying degrees with partial or full power loss.
In at least some partial power loss situations such as loss of compression on a cylinder it will be obvious as the motor will shake the plane significantly along with loss of about 500 RPMs.
 
I think you mean MP gain…a stopped engine has about 30" at sea level.

At high power, you'll feel it. At low power, maybe not.

Wrong engine indications, funny noises, funny smells, rough operation, loss of airspeed, basically, anything not normal.
 
Don't worry, when that big fan up front that keeps us pilots cool stops, you'll sweat bullets in a nano-second.

+1 if you're 500 AGL, don't try the impossible turn.
 
Good question. Might be beneficial to go up to altitude, establish a full power climb, and pull power back just to see what happens.
 
Watch this video, preferably with your headphones on. You WILL know the instant you have a problem IME, as did this guy: http://youtu.be/WbqDTuAQoi4

This is how I hope it happens to me, e.g. lots of wide open field to set down in, airframe be damned. A couple of times in my 150 and once in particular the engine stumbled on takeoff. Not like a smooth rollback in power, but more like sputtering. I had runway beneath me and dove for the deck and nearly ran off the runway but got stopped in time. On the ground my knees were knocking.

In this particular video, my own senses screamed to turn back and land, but fortunately this pilot made a better choice. I can't recall a better real-life video for human factors during an engine problem on takeoff scenario than this one, although that Bonanza vid, which was a true engine out, was educational as well http://youtu.be/94IURXCoY5A
 
JohnAJohnson said:
Good question. Might be beneficial to go up to altitude, establish a full power climb, and pull power back just to see what happens.
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Hopefully he did this more than once in training. Years ago , my instructor pulled power usually around pattern height and asked " where will you land " and proceeded to let you get very low over farm land before restoring power. Excellent training. Below five hundred your choices are very few.
 
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Ryanb said:
This may be a dumb question but it never hurts to ask. How do you know if you really have an engine out or start to lose power? Say your taking off (or even at altitude) about 500ft agl and you have a failure, what are signs you will notice that are out of the ordinary? Obviously the engine sound will change and you may feel deceleration but as far as engine sound goes, i assume it will be noticeable. We get accustomed to how everything normally goes so if something were to develop i feel like its important to know what is actually happening ASAP and do something instead of "something doesnt seem right, but im not sure if its actually happening" and not your mind playing tricks on you if that makes sense.
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Oh... You will know it instantly.......

500' AGL... = STRAIGHT AHEAD.....

Find a safe place to stuff it....:yes:
 
Jimmy cooper said:
Hopefully he did this more than once in training. Years ago , my instructor pulled power usually around pattern height and asked " where will you land " and proceeded to let you get very low over farm land before restoring power. Excellent training. Below five hundred your choices are very few.
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Sure, lots of power outs, but we never did any in the initial climb-out speed, attitude and power configuration.
 
passenger's voices get much louder.
 
To paraphrase Mr. Justice Potter Stewart writing in Jacobellis v. Ohio, 378 U.S. 184 (1964), "I may not be able to intelligibly describe it, but you'll know it when you see it." Things like high oil temp and low oil pressure may be indications of impending failure, but when the failure actually occurs, there will be no doubt in your mind that it has happened.
 
I felt a deceleration during climbout, pushed the nose down for speed and glanced towards the power indicators (tach, MP, Fuel flow) and saw them all unwinding, pushed all the go levers forward (throttle, prop, mixture, fuel selector) while turning back to the airport and calling tower. "Nxxxxx is returning, no power".

I had reached pattern altitude and on crosswind. A 180 turn towards the runway put me on base to land the opposite direction.

The answer, how did I know? I felt it, maintained flying speed, confirmed it (checked gauges), applied corrective action (levers forward), alerted ATC, and landed.
 
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MAKG1 said:
I think you mean MP gain…a stopped engine has about 30" at sea level.

At high power, you'll feel it. At low power, maybe not.

Wrong engine indications, funny noises, funny smells, rough operation, loss of airspeed, basically, anything not normal.
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A windmilling prop will not have surface level MP.
For me to the engine was still running, but not producing power, barely an idle.
MP was less than 12.
 
Nobody told him the obvious indicator if the power loss is subtle, and not a god-awful bang and vibration like many, is:

Airspeed decaying in a power and pitch configuration when it should not be decaying.

The more technical form of this is what pros would call "flying a profile".

The airplane should perform a certain way fairly consistently for a typical set pitch angle and power setting. When it doesn't, you switch to the *briefed before takeoff* alternate plan.

Airspeed decaying, the immediate required action is pitch down. Now.

The secondary is to start the memorized flow for power loss/engine out. This is where the engine instruments come into play. Not before airspeed is maintained.

Memorization of the engine out/restart checklist items is required. It is going to be very difficult to futz with a checklist at 500 AGL.

Next is execute the pre-briefed plan. The plan must take into account obstacles, wind, pilot skill, airplane capabilities, and a fudge factor for error.

At 500' AGL in a single, it's always "Land straight ahead, try to miss hard things, once on the ground, maximum braking."
 
BillTIZ said:
A windmilling prop will not have surface level MP.

For me to the engine was still running, but not producing power, barely an idle.

MP was less than 12.
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I bet that glance at the MP gauge is forever available in your mind's eye, eh? Ugh.
 
BillTIZ said:
A windmilling prop will not have surface level MP.
For me to the engine was still running, but not producing power, barely an idle.
MP was less than 12.
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Your throttle failed closed, eh? Or intake icing?

You won't get that much vacuum without an air blockage and good rings.
 
denverpilot said:
Airspeed decaying in a power and pitch configuration when it should not be decaying.

The more technical form of this is what pros would call "flying a profile".

The airplane should perform a certain way fairly consistently for a typical set pitch angle and power setting. When it doesn't, you switch to the *briefed before takeoff* alternate plan.
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The problem is that this can also happen due to strong downdrafts, so unless the decaying of airspeed is much more marked than anything you have ever experienced before in that airplane, this is not a reliable indicator of *subtle* failure.

It's happened to me several times here in VT and a couple of times back in MI too. On climbout after the miss, airspeed getting down to 60 kts, barely climbing at 200 fpm. Loss of power or downdraft? It proved in every case so far to not be engine failure, but this is NOT easy to diagnose in real time, particularly under the hood. In the end I relied on normal readings plus the lack of roughness or shaking to convince myself that this was "normal", but I'm not sure that there aren't subtle failure modes where the symptoms are indistinguishable from normal functioning in a strong downdraft.

Not great comfort to the OP, I know. :(
 
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In my case it went from normal operation to shaking like crazy. From analysis of the post mortum failure, it's unlikely gave any detectable warning.
 
MAKG1 said:
Your throttle failed closed, eh? Or intake icing?

You won't get that much vacuum without an air blockage and good rings.
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Fuel line was sucking air through the Cessna style pull drain. It took a while to find that one. No fuel or not enough fuel to the engine for power.
 
For me, the two biggest indicators were rapidly decreasing airspeed and rapidly increasing quiet. :D

To echo what the others have said, you'll definitely know. ;)
 
My case it was loss of cylinder and EGT shown on the engine analyzer.
 
Have had two instances, there was no doubt both times.

Deceleration, less engine noise, EGT plummet, MP dropped like a stone.

Have had partial loss before, MP dropped slowly.
 
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