Helicopter Engines?
 

Guys this may be a silly question, but one I've been thinking about none the less. With the options for truely high performance "45" size engines limited to Rossi or costly Nelson/Jetts....would there be an option to use a helicopter 50 size engine in an airplane application.

I would love to get my hands on a NIB YS 45..but seems like they are few and far in between. But YS does make a 50 size helicopter engine and that has me thinking. Could this be used on my speed delta with a 9-8 prop and tuned pipe? From pics looks like it just needs a prop drive and washer.


Also given even the cheapest heli engines run in the high rpm band, they could also be used?...OS, TT, Etc.

I know there's GMS, Tower, Supertigre etc out there with 45 size engines...but nothing like the old YS45....and I just can't sneak a $300.00 engine past the wife. Can pick up a helicopter engine for about $200.00. If this is a totally dumb idea, I can always do as initially planned and go with a new Rossi 45 and full length macs tuned pipe.

what do you think?

RE: Helicopter Engines?
 

The heli engines actually work nicely --- as you noted, the better ones are timed for higher rpm these days.

I sympathize with the money vs wife thing.

But keep in mind.... to your $200 heli engine you will have to add a $70 tuned muffler or pipe setup to truely take advantage of the power and develop the rpm and torque needed for the aero application. Without the exhaust system --- you might as well be using a TT46pro or OS50 aero engine to start with. Plus for most heli-engines you will need a special shaft-extention nut - the output shafts are often too short for a prop hub... thats another $10-20.

Retired or re-built heli engines are sometimes a good value. There were a bunch of YS80 and OS70 engines floating around fairly cheap for a while. With the right exhaust system and suitable prop .... they have some good higher rpm/speed potential.

Speaking of which... since you are on a budget... one of my favorite combos.... TT46pro and Jett-stream.
For most .40-.50 size Q-500, deltas, shrikes, etc it is a performance/$$ setup that is hard to beat.

RE: Helicopter Engines?
 

i have seen YS 90 size helicopter engines and others for sale and wondered the same thing.

RE: Helicopter Engines?
 

You just got to keep your eyes open and look at adds here and EBay. I just won this YS 45 with pipe and header on RCU for $145. By the looks of it, the engine may never had seen full power, the header looks way long. Ive scored 4 of these engines this year and 2 are NIB and could of had more, just wasnt in the mood. This is about the going price for NIB or used with pipe.

http://www.rcuniverse.com/market/item.cfm?itemId=347570

RE: Helicopter Engines?
 

I snaged this from another forum (tachometer readings):



RE: Ys 45 2-stroke - 8/26/2007 8:07:43 PM
sydc

Posts: 21
Joined: 5/1/2006
From: Skirlaugh, UNITED KINGDOM
Status: offline Hi Wood489,

I have recently converted a YS91st to aero, I believe that the 91st is a bored out 80st and should have the same output shaft threads. Here are the part numbers I used to convert the 91st with the output shaft thread of 8x1mm.

Drive washer YS part number F9323
Drive washer retainer YS Part number F9324
Reach through prop nut Tru-Turn part number TT-0813-A, (these prop nuts are designed to take the Tru-Turn alloy spinners).

Hope this helps,

Regards, SydC.

(in reply to wood489

Unquote

Would it be cheaper? I dont know, but folks are doing it. It may work for smaller engines too but you need to do your parts research here:
http://www.webra-austria.at/motor.php?lang=EN