Jetstream 32 - engine quit

[ChristophPreinfalk]

I know this is not Javier's Jetstream 32 support forum, but please let me ask this question here anyway, since I know there are some Jetstream 32 pilots on PE.

Yesterday I was attempting to do my first TEC Route (I passed I-4 a few days ago ... yay! ) flight based on focus fields, using a non-X-Plane default plane: the Jetstream 32. Everything went really well, got clearance, fired up the engines, everything as per checklists, lovin' it. Cleared for take off, headed the assigned heading, then headed towards the first VOR of my route. Climbed to 10,000 ft, cruising along right at 250IAS, throttles at something like 70% or so. Oil cooler flaps set to automatic to make sure nothing gets too hot. All engine indicators either withing the green range or below. About 20 minutes or so into the flight, all of a sudden the left engine quits. No bells went off, no whistles, simply lost the engine. I kept flying for another minute on the right engine, but lost speed and eventually simply checked in with the controller to tell him that I'm having tech diffs and will log off, and I apologized. I know, I should have gone through the whole emergency procedure, but I'm not ready for that yet.

So the question to the collective PE forum user brain: Any ideas what I could have done wrong, or should I chalk this off to a random failure? I've been flying the Jetstream off line for longer distances before and I never had an engine quit on me (apart from flying full throttle for a long period of time, which I didn't do this time, I didn't even hit full throttle during take off, constantly watching the engine dials ...)?

[Keith Smith]

The manual states that if you exceed 100% RPM for more than 5 minutes, the engine will quit. Check your EGT's, torque, and RPM. Version 1.02 of the JS32 added an 'rpm alert light' (orange) so you can tell if you're exceeding the number.

Watch the I-5 training video in the JS32 closely and you'll see I spend quite a bit of time monitoring engine performance for that very reason (that video was shot prior to the 1.02 release which included the alert light).

[ChristophPreinfalk]

Thanks for the response! I was flying at about 70% throttle (cruising at 250IAS) and the numbers were within the green range or below, and I didn't every hit full throttle during the climb. I sent an email to Javier, and I sent a message to X-Aviation, I'll see what I get back from them ...

[Keith Smith]

The % throttle is not relevant. You can be under the torque limit, under the EGT limit and still go over RPM limit. I suspect you were overspeed. I can't get it past 240kias or so before the prop governor hits its coarse limit and now you have a fixed pitch prop. As you speed up (airspeed-wise), the RPM then slowly starts to creep up. I complained loudly about this in the forum as I can't find a single r/w turboprop pilot who has seen this be an issue, but there was no resolution. I would think the prop governor would have enough authority to keep the RPM below redline at any speed up to VNe, but it is what it is.

Zoom in on your RPM gauge while you're cruising at 250kts and let me know what % it is. If it's over 100% (by even a fraction), then you have your answer.

[arb65912]

Zoom in on your RPM gauge while you're cruising at 250kts and let me know what % it is. If it's over 100% (by even a fraction), then you have your answer.

When engine is over speeding it will be a yellow/orange light lit and if it continue for more than 5 minutes, engine will be gone. This light is an easy way to judge the RPM without zooming in to the gauge.

[ChristophPreinfalk]

Tried again tonight and you were totally right. It was the rpm. During climb everything was in the green range and there were no warning lights by the instruments, about 90% or so throttle. But once I leveled off at 10k ft and the airspeed increased and the props unloaded, the rpms increased and those small rectangular lights under the rpm indicators went on. I then had to quite decrease the throttle to keep them off.

Thanks for your help!

[Keith Smith]

Glad it helped. You're welcome. You should see how much fun it was to keep an eye on it before the yellow light was there

[Daddy O]

You sure the engines were not torn off by vmax? Xplane does rip off engines if you have the realism set for it. I have left a dozen or so virtual engines in the grand canyon, and even had one wretch itself out of my piper in straight n level flight, dunno why.

[Keith Smith]

If that was the problem, it would've ripped BOTH engines off the minute he exceeded the trigger speed in X-Plane (I have that setting turned off in X-Plane because most aircraft designers don't set the limits properly. Control surfaces don't rip off the minute you exceed a limit by 1kt).

He described a very common problem with that aircraft, and the same solution that worked for everyone else also worked for him.

Also, he reported one engine shutting down, not both.

[ChristophPreinfalk]

It was the over revving for sure. And I noticed that the left warning light comes on before the right one (last night during my successful flight), which is consistent with the left engine quitting the night before.