Well done for sure, but a PT6 failing?

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but a PT6 failing?

After doing a few years of casual research, I've found that PT6 failures are quite common. If I were flying a 208, I'd try to get a conversion with a TPE-331. Simpler, more robust, more efficient, double TBO. All about the money I suppose.

Did not know that. I had just come to figure a turbine was always more reliable than a recip.

From Wikipedia: The Pratt & Whitney Canada PT6, produced by Pratt & Whitney Canada, is one of the most popular turboprop aircraft engines in history.[3] The PT6 family is known for its reliability with an in-flight shutdowns rate between 1 per 127,560 hours[4] and 1 per 333,333 hours.[5] Time between overhauls are between 3600 and 9000 hours and hot section inspections between 1800 and 2000 hrs.[6]

Then again, it is an old design.....

In a 208, the TBO is 3500. Most Caravan crashes involve failure of said PT6 best I can tell. That would include the gearbox which is integral to the powerplant. Some guys swear by em but I'm not impressed. They have other operational issues too.

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Originally posted by DOPPELGANGSTER:

quote:

but a PT6 failing?

After doing a few years of casual research, I've found that PT6 failures are quite common. If I were flying a 208, I'd try to get a conversion with a TPE-331. Simpler, more robust, more efficient, double TBO. All about the money I suppose.

Say WHAT? A Garret more reliable than a PT-6? Whatever you are smoking you'd might want to consider moderation. Yes PT-6's fail. But the reason that you hear about PT-6 failures more often is that there are more PT-6's running around by a factor of about 100.

I've flown both. The Garret is way more finicky than the P&W. Talk about a gear section! The Garret has a 66 to 1 reduction gear from the turbine shaft to the propeller. Not to mention that is has asymmetric cooling issues and shaft bow issues. The two most common types of failures in a Garret are a high pressure fuel pump shaft failure or a gear box failure.

By far and away with the PT-6 it's a fuel feed issue of some kind.

The PT-6 is more robust. The TPE 331 is more efficient.

And with that being said both have a far greater reliability factor than any piston engine that has ever been built.

Interesting, guys who are working on both and installing both are saying that the PT6 is a POS. It's magnesium gearcase is a toy and it ingests it's own bowels quite often. It has HALF the TBO of the TPE. Never heard of a shaft bow issue on a modern TPE, maybe that was in the 70's? Then there's the whole two shaft coupler lunacy, what the hell is that all about? Three shafts in the big ones. DUMB. I HAVE been told that the TPE is more vulnerable to FOD than the PT-6. Spoke to a guy who operated multiple PT6 powered HO 208's, his comment was along the lines of it makes no power, it will blow up if you push it, the already low TBO is BS, wish we hadn't bought em. Are you talking recent experience with latest variants or back in the day? Also, lumping a PW120 or 150 into the mix isn't a valid comparison.

I am comparing the TPE -3 through the -10 SRL to the comparable time frame PT-6 engines.