Reading CrashTalk this am, looks like there have been several "engine failure/uncommanded power rollback" incidents in PA-46 turboprops.


Is this more common than expected? Something unique to this airframe?

In ag planes it sure is rare to see a PT-6 quit....and of the ones I personally know about, they are usually *very* high time engines (like 10,000 plus hours).

MOR is your friend with SETP’s as has been said. Don’t know if it helps real close to the ground though. Roll back has not been an issue in the TBM PT6’s that I can think of. Certainly possible for the FCU to fail and allow engine to “roll back”. Good to brief the response, MOR, before flight and procedure if needed.

What’s going on with the PA 46’s?

I have heard that the fuel controller has been the issue(but that might not be right) in the M600 there was a change in the fuel controller at serial #81 and that was to a Woodward controller.I know that the starts with the old one on a normal day the ITT is around 770-820 and with the Woodward it is around 640-680 ITT.If the fuel controller rolls back PWC does not count that as a engine failure so in their caculations there has never been a engine failure in these instances.I have forgotten who Manufactured the first edition of fuel controllers for the Meridian and M600.

The Meridian PT6A-42A has the Honeywell FCU

The TBM's have the Woodward

I did some research and the Honeywell was the fuel controller on the M600 also through serial #80.

Stan,

I know you and, just like me, the EPA endangerment finding has me looking at Jetprops...

A JetProp would be a perfect airplane for us. It has enough payload for the two of us, and we seldom fly with pax. It gets 25% better fuel specifics than the B-55-P2 and with a card the fuel is considerably cheaper, and 30% faster.

But my hangar neighbor sold his TBM and bought a Phenom 100 because he could not stomach flying it at night west of Denver. I guess I don't fly so I will keep looking. Right now there are not many to choose from and the prices are ridiculous.

Ron Calguar posted in another thread that one of the secrets to happiness is to "want what you have." Both of us do pretty well in the airplane department. Maybe Stan, we should just want what we have.

Doug,I would recomend getting an insurance quote early because there are few underwriters that will writr insurance for the jet prop.

I think with the rollbacks there is a lot of the same event told 10 different ways by 10 different people, but it is very rare. But Pratt did come out with some SBs on the old honeywell FCU’s. They were only voluntary, but from what I can tell were directed at the rollbacks. When the FCU’s were overhauled or complied with the SB those FCU’s should be mostly updated. You can over-ride the FCU with the MOR lever. Hopefully pilots are training that every year at recurrent. Not hard, just a very sensitive backup throttle. As Joel mentioned Piper went to the Woodward, which has the coolest starts I have ever seen. There is almost no time needed from shutdown to restart. I fly day/night, VFR/IMC, over the rockies regularly, and don’t worry about the engine. Not to mention the P46 turbines have a 17-18:1 glide ratio, you will essentially always be in glide of at least 1 airport over the rockies. Just follow airways, which follow lower terrain and towns, and be cautious with GPS direct routing, which can put you over some wilderness. The 2 areas that come to mind are the Idaho wilderness north of Boise and the Utah wilderness over and south of the uinta’s. Other than that always going to be a place to land. Even as a glider. One of the engineers on MMOPA once demonstrated that a Meridian at typical cruising altitudes had more landing options than a Baron single engine over the rockies. Interesting point.

What is MOR?

What is MOR?

MOR=Manual OverRide.

SETPs have this lever, which I have used in training many times. Manually controls the system in case of a rollback where the engine remains on but the throttle control doesn’t work. I’m being very general here for the sake of simplicity. That’s why Pratt doesn’t count it as a “failure” and I agree with them. You still have ITT, NG, etc. Torque goes down. If you look at the gauges and that’s what you see, engage the MOR. If you look at the gauges and you don’t have ITT/NG, you’re a glider unless you can restart.

PT6 accessories occasionally fail on all these aircraft, like the prop governor sensor which happened to me - everything was running fine on takeoff and initial climb into the Houston Bravo, but the prop RPM indicator bounced around wildly then went to zero and I got the CAS message. Plane was humming along fine. After stopping my climb to investigate, I did a non-emergency RTB with ATC and we got the part shipped out by fedex and fixed on my field.

Our M600 has the original FCU. Never had an issue with it. Start temps definitely higher than the Woodward but I don’t believe you can swap one for the other… there is a six-year overhaul period for the FCU, which we will get to within a year or so. If not this annual, then the next one.

I have literally never worried about engine failure in our airplane. I practice the MOR in case of a rollback and have landed using the MOR several times as well has done air work with it. And as Chuck says, these airplanes are great gliders. It takes a heck of a lot to stop a PT6 once it starts … and the MOR is your insurance policy. I have not lost a wink of sleep about this issue.

I don’t know that the PA46 turbines are any different than the other SETPs with Pratts, other than the FCU choice but I have not done any incident research either. I worry more about getting contaminated JetA somewhere than a rollback…

Cheers

PS: Our recurrent is coming up next month and I’m sure I will get another chance at the MOR - it’s actually kind of fun flying the plane with it!

I read an interesting statistic that the piston powered Pa-46 has a lower accident rate from engine failure than the turbine over the 10 year period that was reviewed. These are fairly recent numbers and the rate for both was very low and I am sure there are many variables but just throwing that out there.

I quoted Ron this am...in this same context.



I'll add you to the "Be content" chorus.....



stan

Can you provide a source for this?