Cessna Caravan TPE331 Conversion

[nomorecatering]

I hear that Cessna wont allow the TPE331 Supervan STC conversion to be done on Caravans with the G1000 panel. It seems Garmin is willing to write the code for the new engine but Cessna wont hear of it. Thus, classic Caravans are back in high demand.

Does a TPE equiped Caravan really have the edge on Chieftains for the bank runners, considering cost?

[wishiwasupthere]

I think Wagga Air Centre is running a Caravan out of Bankstown now on bank running. Would love to have that job!

[WannaBeBiggles]

If the Texan conversion does this well on floats then I'm sure are some good reasons to put one in a wheeled van :ok:

900 shp Texas Turbines Supervan 900 vs. Stock 675 shp Caravan in Takeoffs on floats.avi - YouTube

[Sunfish]

Garrett/Honeywell TPE331?

Is their reliability and spare parts support still a byword for horrible?

[Super Cecil]

They would want to be cheap to make up for the noise :}

[T28D]

Unlikethe oppositions engine the Garret is modular and readily fixed if it does give trouble, generally TBO is 7000 hourswith Hot Section at 3500.

Speaks for itself really, the other air through the engine backwards is limited to aTBOat 3500 and Hots at 1000.

Never had a Garret give a moments worry in flight, can't say that for the other brand.

Parts are easy to get and there are a number of O'Haul shops approved in OZ.

[Propstop]

It is horses for courses: the PT6 can be maintained and operated in third world countries and will run in a satisfactory manner, but a TPE331 does require an amount of skill and precision from both pilots and engineers to get the best out of it and not cook it.
Both engines are excellent in their respective niches. In saying that the 208B does require some serious horses to perform in anything greater than ISA and the TPE fits the bill there.

[tail wheel]

"....the other air through the engine backwards is limited to aTBOat 3500 and Hots at 1000."

I thought the base HSI period for a -114 was around 1,500 hours (or more?) and I think most Caravan engines would be on a TBO extention program? I have known -27s and -34s on condition to run 10,000 hours TBO.

The video clip proves only that 900 HP is 33% greater than 675 HP with corresponding increase in aircraft performance. There is also a fair chance that if one were to install a PT6A-67 (1,200 HP) in the Caravan it would probably outperform the Garrett equipped aircraft?

[T28D]

Taily OK the TBO and HSI times vary a lot model to model and are to a degree operator dependent , but as a rule the Garret times are significantly higher than the backwards air engine.

And for the noisy quote, yes taxying they are noisy, exposed compressor, with the advantage that the RPM of the compressor whilst noisy rejects ingestion of stones and fod in the main, also more ice tolerant in flight.

Not any noisier than the competitor in flight.

The -10 engines are easy to start and keep cool in the start cycle, there is no doubt the engines have evolved over a LONG time and early models were not anywhere as efficient or user friendly as the current evolution.

[tail wheel]

From one who is so dependent on the original big round Pratt's product, I'm surprised you don't also support the greatest small turbine available to aviation! :} :}

[T28D]

Taily the big round engine is a Wright 1820-86 , the B18 small round pair are 985 Pratt.

I like Garrets, like Wright radials they are bullet proof if you know how to handle them and start into wind.

[Super Cecil]

I like Garrets, like Wright radials they are bullet proof if you know how to handle them and start into wind
I'm sure you'll get a few disagree with you, off tarmac work Garrets have a deserved reputation for not running anywhere near their full time. Not many have full trouble free life on AG, Pratt's on the other hand usually are the opposite. AG is a harsh enviroment, same as bush operations that a lot of those Garret Caravans are headed for.

[AdamFrisch]

Plus Garretts are certified and won't mind a bit to run on anything - Avgas, Diesel, Mogas.

[mattyj]

Isn't the big advantage the tpe's improved performance for the same fuel burn?

[The Green Goblin]

THe PT6 was originally designed as an oil pipeline pump in Canada.

The Garrett, an american war throw away helicopter engine.

I'd rather have the one built to fly than the one built to stay on the ground :)

From my perspective the Garrett was a better engine. A little trickier to start, but if you kicked it in the guts with a series start once you had light off (starting the first engine) it was always a faster, cooler start. A battery assisted start on the second engine was preferable to a cross generator start to save current limiters.

The nicad batteries will also add to starting woes if they have not been upgraded to the lead acid spec.

Nothing worse than on a 40 plus hot and high day watching a poor soul starting a hot Garrett. :cool: it could sometimes take a while!

I certainly miss the metro salute on every ramp you arrive on :p

[Super Cecil]

I certainly miss the metro salute on every ramp you arrive on
That's the fingers in the ears and the look of incredulity? Everybody here HAS to admit on the ground they are horrendously noisey. When you unplug the ground power (Single injun) the noise is such your expecting something to come out the side. :8

[nomorecatering]

Now if you want realy really loud, try unplugging a GPU cable from the engine nacel, which is only a metre or so behind the prop after its started.

One day I was training a newbie, his first day on the job. Never been around aeroplanes before, let alone walking to within 1m of a spinning prop. This time, the crew gives us the GPU disconect signal. Just as the newbie unplugs the GPU cable the crew lifts the props off the start locks. Poor newbie needed a change of underwear.

On their return, I firmly said to the crew that if they ever did that again, i would personally insert the GPU cable in a place where the sun dont shine.

Never happened again.

[Wizofoz]

Would a Garret equipped Caravan be cleared for IFR commercial work in Australia? I thought it was pretty much only PT6 powered aircraft that had that approval.

[Grogmonster]

I hear from a reliable souce that Cessna will now produce the Black Hawk Dash 42 conversion off the assembly line which may explain their reluctance to help the Garrett cause.

Groggy

[airag]

Agree with Taily on this one , Garretts start slower and hotter , idle faster and noisier ( suicidal ground crew), Very high pucker factor leaving the box office whilst still in ground idle ( yes bush lawyers we do have dipensations!) , need their own engineers due reliability ( Ag' and RPT) , love to ingest dirt/dust and birds .... but do have slightly better SFC once they're going !

Yep I reckon a -67 'Van would be the go.

[18-Wheeler]

DvshBFJSoDo

A bit of reference here.
(And this is a good start!)

[ironbutt57]

-67 gonna gobble fuel though...water manoeuvrability and fuel efficiency make up for the exterior noise of the TPE...I'll take the TPE anyday...

[ironbutt57]

"18" if you could look up the hiney of a PT-6 you would see the same thing....