PT6

[pym]

Just thinking today that with the introduction of the AW139 into service, the Air Corps are eventually going to have at least 22 PT-6 engines on the books, and possibly 26 if the Agusta options are ordered, not to mention PC-6's, CN-295's or anything else.

This compares to only 6 a few years ago.

Does this translate into easier training for maintenance crews and better economics, or are the PT6 variants so different that they may as well be completely different engines?

Also, something which may be of interest:
http://www.pprune.org/forums/showthread.php?t=204240&page=9

Long and detailed topic on the AW139. On that particular page the choice of engine on the Heli is under serious discussion. Interesting stuff - it would appear there's no danger of these birds being underpowered, but that comes at a cost.

Huge amount of details elsewhere in the same topic, discussing everything from exhaust fractures, to wind screen breakages. All part of the early days of a new helicopter.

[GoneToTheCanner]

Hi there
One thing you can say, for an absolute cert, is that PT-6s are the definition of reliability. The A-41s on the King Air are so reliable,they'd be the equivalent of a Honda Civic engine.I don't know much about the PTs on heli applications but they do have millions of flight hours logged so they must be as good as their fixed-wing brothers.They have a few quirks(shorter time-between-overhauls)because they are an old design but in essence, they are easy to run and maintain.As for commonality, they can probably swap some but not all parts but probably can share filters and igniters (which are the most used service items) and can be got anywhere.P and W also have a very thorough service network so expertise can be had at the touch of a button.PT-6s are also used as land and sea-based industrial engines and if they can survive that, they can survive anything.
regards
GttC

[SousaTeuszii]

GTTC,
Agree absolutely on the PT6 reputation. P&W service support and first class customer service is also one reason why the Air Corps choose PW engines for the 135s as oppose to comminality with the Turbomecca engines in the Garda 135.
ST

[sealion]

With regard to Turmomeca, I understand the french could be difficult when dealing with civilian contractors repairing military aircraft.
When Eithne was being built, they refused to provide the dockyard with the specifics required for designing the deck handling and ILS system.
They would only provide the mil spec details to a military customer....

[SousaTeuszii]

Hi Sealion,
I think that is just a general rule of thumb with all contractors. They are very cagey about giving any info on military or even paramilitary equipment to civil operators.

With regard to PT6 stats as the most reliable engine in the world can anybody tell me how this is worked out. For instance I have heard that the recent spate of forced landings by PC12 after engine in flight shutdowns are not included in the in flight failure figures. This is because the problem i believe was with a governer module made by another company. i.e. the PT6 didnt fail, but the result was the same.
Also in a reletively recent event a pilot shutdown a PT6 on K240 which was pulling itself apart. Again the engine didnt actualy fail so it was a precautionary shutdown not an in flight failure. Another 30 secs and it coud have taken the wing with it!

Just wondering, how common are shutdowns or failures that engine manufacturers can blame on other companies? Should we believe company stats?

[GoneToTheCanner]

Hi Souza
If a PT-6 had a failure to such an extent that it would potentially tear a wing off, then it'd be the first ever.I'd guess that the pilot got a vibration warning and shut down.If a PT-6 suffered a blade failure, it would be contained within the engine or exit via the exhaust.Also, PW would have such gen about failures and other incidents from those engines that are on a factory-controlled power-by-the-hour scheme and those operators who communicate with the manufacturer directly.Their field reps, like others, keep a very close eye on their products.
regards
GttC

[SousaTeuszii]

GTTC,
I understand that and agree but my point is when does an in flight failure become an in flight failure. Is it right to say that an actually failing engine was shutdown by the pilot before failing and therefore is not counted as a PT6 failure? Even if the engine must be scrapped afterwards?
I am afraid that in todays marketing this is how I believe stats are petered off to whittle down the number of failures.
ST