V12 Alternatives

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MEDEVAC

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Apr 22, 2020
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Brisbane, Australia
Hi folks,

Does anyone have any insights into the turbo-prop world? I’m looking at a power plant for my build and thinking ahead.

The aircraft was originally designed with a Falconer V12 in mind but they are no longer available and have serious limitations. Why buy an obsolete engine with no support or spares and a chequered history? Not to mention the lack of a PSRU.

To that end, and slightly serendipitously because of the COVID situation trashing aviation in general, I thought of the potential availability of turboprops. There must be some cheap(er) ones available seeing as planes aren’t flying.

Who has what? 650hp and up? How much do they cost?

More powerful
Less maintenance
Abundant
Spares easily available
Lighter
More service techs available to work on them?

What do you think?
 

TFF

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Apr 28, 2010
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Memphis, TN
Right now there are no cheap turbines on the market unless you get a brother in law deal. I can’t see one cheaper Than a couple of hundred thousand. I’m partial to a GE CT7 I don’t know how much nose you have on your plane. RR, Walter, Garrett are probably “cheaper” than Pratt and GE.
 

PMD

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Apr 11, 2015
Messages
242
Location
Martensville SK
In that power range, the front runner is Walter, but you need to do a LOT of looking around to find a good used engine. One of my good friends built an 8 place bush plane using a 601D (at around 900HP) and matching Avia propeller (search posts by Craftsven). Once GE sunk their greedy teeth into Walter, the cost of service parts increased as much as 10x. There are a few independents who provide some of the critical things for much, much better prices, but overall, if you can find a compete used engine, chances are you can fly a lot of hours without any more than staggering fuel bills for some time to come. Because of the weight difference, though, just plugging a 601 onto the nose of something intended for a cast iron V12 isn't going to work. If the airplane isn't built yet, then the re-design needed can be accommodated.

Oh: If you have any connections to Eastern Yurp, that is where you will find more Walter engines than on this side of the pond. Make sure to get the prop with it.
 
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delta

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May 26, 2011
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Brookside Utah



The Chevy engines could probably be made to produce the hp reliably, but not sure about the prsu's.
 

macquistan

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Mar 25, 2020
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You might want to talk with Elliot Seguin. He did some flight testing and ferry flights on a Walter powered Thunder Mustang. He has also been doing the flight tests on a LS powered S-51. I think he could give you a great comparative view of the two types of power plants in very similar airframes. ...By the way I think the Walter powered Mustang had decreased load limit compared to a stock Thunder Mustang. It's something you might want to investigate as well.
 

MEDEVAC

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Apr 22, 2020
Messages
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Location
Brisbane, Australia
Thanks guys - good info.

I actually tried to contact Elliot about a year ago but couldn't get through to him. I was looking at a 90% built kit with a Falconer. It sold and I moved on but now I have an unbuilt crated kit and can start from scratch.

I have sourced a Honeywell TPE 331 that might work. The owner wanted $100k then $130k then he said it might be worth $160k after he does some work to it. I backed away as I felt he was trying to inflate the price. I'm in no rush. It won't be ready for an engine for a couple of years.

I looked into a Walter but wasn't thrilled. They are expensive as mentioned and they have a 4G limit which is not what this aircraft is designed for so I'll probably keep looking. Maybe a V8 would work - it will depend on where things get to in the next few years. No rush :)
 

dino

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florida
BMW V12 made several types over the years as well as current version about 600hp stock
 

thjakits

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Jul 3, 2014
Messages
66
Location
Panama, Rep. of Panama
IF you are willing to spend a couple k of $ for a used turbine, you might as well check out these guys!!
V12, 500-600hp, PSRU - whole package designed for aviation!


Cheers,
thjakits
 

MEDEVAC

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Apr 22, 2020
Messages
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Location
Brisbane, Australia
I just got off the phone with Pacific Turbine in Brisbane, QLD.

They have a 1000 hp Honeywell TPE-331-11U for $110k USD with 3000 cycles before overhaul.

I think when the time comes, I’ll go this route. The power and reliability are undeniable. There are a few technical challenges such as how to route the exhaust butI like the idea of ducting it out the lower dogbox. With an integrated gearbox, it weighs about 300 lbs less than the Falconer assembly as well and costs almost the same.

I asked about putting down a deposit and paying it off over 2 years but they wanted 25% non-refundable, 6-8% APR and balance in 12 months which is too much too soon. I’m sure there will be plenty around when I am ready.
 

MEDEVAC

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Apr 22, 2020
Messages
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Location
Brisbane, Australia
420 litres capacity = 720 lbs of fuel.

it consumes .534 lb/hp*hr approx (-10 fuel figure)

Cruise at 600hp = 320lbs/hr

So 2 hrs of endurance at 600hp.

A lot longer at reduced power, much less on a sprint!
 

thjakits

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Panama, Rep. of Panama
Got enough room for fuel to feed the turbine?
420 litres capacity = 720 lbs of fuel.

it consumes .534 lb/hp*hr approx (-10 fuel figure)

Cruise at 600hp = 320lbs/hr

So 2 hrs of endurance at 600hp.

A lot longer at reduced power, much less on a sprint!
I think you look at only 1 hr safe cruise.....
You will use a LOT just getting to cruise - which you will not safe on coming down from cruise...
This thing is thirsty, no matter how little power you think you're going to use, 30 min reserve, 10 min taxi out , 5 min taxi in....
While you are at it, find some drop tanks!

thjakits
 
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