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GreyWolfCherokee
3rd Mar 2011, 23:53
I am putting together a package for potential investors/sponsors for a world land speed record attempt in a turbine powered motorcycle. I have talked to a few people who seemed to know what they were saying, and I was told that a completely psychotic build w/o afterburning should net me in the neighborhood of 5500-6000 shp. My question is this, is this information correct??

sevenstrokeroll
4th Mar 2011, 00:23
I'm a pilot, not an engine expert...but, I've never heard of an afterburning PT6 or any turboshaft/prop engine

I would contact Pratt and Whiteny of Canada directly for information about it.

I can't imagine a motorcycle with a pt6...but what do I know?

twochai
4th Mar 2011, 01:37
If I remember correctly, I believe the gas generator of the PT-6A-66 has a thermodynamic output capability in ISA conditions of around 1650ESHP. Of course, the gearbox is only rated to 950 SHP and presumably the bang from the gearbox would precede the flames from the gas generator as the turbine blades burned up!

It might indeed be described as an 'afterburner' by that point!

SNS3Guppy
4th Mar 2011, 02:50
Afterburner?

Have you ever seen a PT6?

dixi188
4th Mar 2011, 03:01
I've seen flames from the exhaust during a wet start on a PT6 but no afterburner.

If you want 5-6000HP then you need something like a PW150 from a Dash 8-Q400.

barit1
4th Mar 2011, 03:09
Do you really understand what an afterburner is all about? :rolleyes:

V1... Ooops
4th Mar 2011, 07:07
...max. power output for PT6-66... for a turbine powered motorcycle.

Sir:

I think you may have unintentionally posted the wrong model of aircraft engine.

The PT-6 series of engines are turboprop engines - the power is delivered to a shaft at the front of the engine, and a propeller is then attached to that shaft.

It would not be practical to use this type of engine to power a motorcycle because the torque (rotational force) applied to the propeller would also be equally applied to the motorcycle to which the engine is attached. The result would be uncontrollable.

I am going to guess that you are most likely seeking some form of jet engine - likely a pure jet engine, not a high-bypass turbofan.

Good luck...

waren9
4th Mar 2011, 07:10
Give that Yank Jay Leno a call.

GreyWolfCherokee
4th Mar 2011, 14:36
I do know that it is a free shaft turbine and want to use it to drive the rear wheel of said motorcycle. This project is in its' early design stage, and we, the team, know that there are considerable physical and technical questions that we need to answer prior to any full scale building taking place. Not the least of these questions is in fact the torsional stability issue. We are examining several ways to counteract that force without inducing more stress to the frame of the vehicle. Another of the technical considerations is this, can we use bundled carbon fiber/kevlar rods in place of some esoteric metallic alloy of the same or similar strength to weight ratio? So, as you can see, this is not some crackpot throw it together and drive it until it kills me idea. I do want very much to survive my encounter with Bonneville and , hopefully, the record books

GreyWolfCherokee
4th Mar 2011, 14:39
I want the rear wheel of the motorcycle to be driven, not free spinning. Therefore, I will need to use a free shaft turbine along with its' transmission. I have several ideas for dealing with the resulting torsional stresses, that hopefully will not add considerable weight to the vehicle.

barit1
4th Mar 2011, 15:18
There is another possibility.

I've seen pix of the GE T58 (or RR Gnome) - a free-turbine engine - with the free turbine amputated and replaced with a straight nozzle. Some extra fuel was injected into the new tailpipe - mostly for the dazzle factor - but without a variable exhaust nozzle, it a far-from-optimum a/b. :}

Presumably similar surgery could be executed on a PT6.

MurphyWasRight
4th Mar 2011, 16:46
The original post seems to imply that no after burner was involved,
note that w/o whch I read as WithOut.

I was told that a completely psychotic build w/o afterburning


Assuming ithe ntent is to drive a wheel(s?) ( which the shp question implies, please correct me if I am wrong) rather than push the thing like a jet I only have one question.

How do you plan to couple 6000hp from motorcycle to the ground with a wheel of any sort?

Seems things would start slipping well before the 6000hp point was reached unless the wheel had nubs that ran in a matching track or something.
Guess you could get a little extra "down" force by pointing the turbine exhaust to the sky.

In any case can't wait to see the video!

barit1
4th Mar 2011, 21:18
You probably wouldn't need a gearshift on the tranny. Just gear it for max speed, and then the starting and acceleration torque could be easily held just below the point of losing traction.

V1... Ooops
5th Mar 2011, 10:53
I do know that it is a free shaft turbine and want to use it to drive the rear wheel of said motorcycle...

OK, good luck with the project. Here is a URL that might help you get started, it links to Pratt & Whitney's website where turboshaft (as opposed to turboprop) engines are described.

Turboshafts | Pratt & Whitney Canada (http://www.pwc.ca/en/engines/turboshafts)

Michael

Fat Dog
8th Mar 2011, 00:47
Brilliant... hope this isn't a wind up.

Needed something to make me chuckle half way across the world on some sh!t contract my employer currently has me working on. Love the lunacy of some people (meant in the nicest way!).

Good luck.

onetrack
8th Mar 2011, 02:15
I'm with Murphy on this one. I'd like to see the motorcycle wheel that could handle 6000 HP and get that 6000 HP to the ground, effectively?

Oh, wait! I know! Something like THIS, is what you have in mind??

Australia's Monster Motorbike from Hell (http://www.autoblog.com/2008/01/30/Australias-monster-motorbike-from-hell/)


http://i55.tinypic.com/js0lc1.jpg

V1... Ooops
8th Mar 2011, 11:38
Interesting motorcycle design in the picture above. Might be well suited to the flatlands of Australia, but perhaps less than optimal cornering performance in the mountain twisties of Switzerland... :E

I'm not entirely convinced that aviation and motorcycles are a good combination...

http://i979.photobucket.com/albums/ae275/Paneuropean/FlyingMotorcycle.jpg