Deisel Helicopter

[nickn]

Came across this today a two seat Deisel Helicopter Look's like it has just been put on the register here in oz take a look at www.deltahelicopters.com.au

 

[HobbyCAD]

I heared a while ago that Graeme was doing this build, but never saw any pictures. Looking at them now, the machine sure seems good. It seems the Samka has a challenger!!

Looking at the attention to detail of the components, I'm sure Graeme must have done all his R&D well. But there are 2 things I wonder about, can anybody help me out here?

The heli has rotors turning the conventional "American way". I seems the accepted way is for the T/R to push against the torque, ie, it's mounted on the left. Why is this heli pulling against the torque, with the T/R on the right? Has it got something to do with the clean inflow of air? If so, why has just about all the heli's out there have it the other way round?

My second question, referring to T/R rotation, I was taught the accronem, Bottom Aft is BAd. This heli has the bottom blade going aft, thus Bad. Again, most heli's out there have the bottom blade going forward, why has Graeme done it differently?

If I ever meet up with him, I'll sure ask him, to clarify it up for me.

Regards,

Francois

 

[helipaddy]

The R22 has the blade goin the same "bad" direction. but the R44 T/R goes the "Good" direction.

Pint of Guinness to the first person who posts why!
(Only redeemable in Charlie Welds Pub in Robertstown, Ireland!)

 

[Arnie Madsen]

I have been following the prototype build for over a year. Graeme Smith and associates have accomplished a lot in a short time. Lots of posts and build pictures here.
https://www.rotorwayownersgroup.com/forums_c/showthread.php?t=5182&highlight=delta

Roomy 2 place cabin , 3 blade fully articulated rotor , diesel power. Designed for the Australian cattle mustering market .

Arnie
Bell 47

 

[WaspAir]

I seems the accepted way is for the T/R to push against the torque, ie, it's mounted on the left. Why is this heli pulling against the torque, with the T/R on the right? Has it got something to do with the clean inflow of air? If so, why has just about all the heli's out there have it the other way round?

I'm not convinced that there is a single accepted way.
My Sikorsky S-52 had a pusher tail rotor, and my Bell 47 has a tractor tail rotor, and both designs are from the same era with the same main rotor rotation direction. The last Brantly B-2 I spent any time with had a tractor, I think, and the last Enstrom I flew had a pusher. And if my memory is reliable, the Black Hawk has a tractor (as does the new S-92), while the SH-3 Sea King has a pusher, all from the same company.

And how does one count the AS365? Is that a "tractor" inside the fenestron, running on the left side of the shroud, pulling against the "French" direction torque?

 

[MikeSherman]

Helipaddy -

I'll take a stab at it...

I think Frank had the tail turning away from the MR wash simply due to making the TR gearbox smaller and lighter. The opposite direction would put the gear on the other side of the pinion, probably needing a support bearing.

The current design allows the gear to cantilever out but spin with the downwash.

Close? Ballpark? ;-o)

-Mike

 

[helipaddy]

I owe you a pint, You'll have to come over here to get it though!
You are welcome anytime!:yo:

(Or I could drink it for you!)

 

[MikeSherman]

Helipaddy-

Hah! Finally got one right! ;-)

Enjoy that pint, I doubt I'll be in your neighborhood anytime soon. Thanks anyway.

...sorry for the short, thread hijack...

Regards,

Mike