<snip>

I'll work on those numbers for the 900 HP 3 rotor.

That is real interesting on the small diameter variable pitch prop.

As fate would have it Butch is working hard on a variable pitch prop
design as we speak. Hopefully he will have the prototype done by Sun &

Fun

and will be able to display it there.
The parts in this picture are from a earlier, now obsolete prototype.
(too heavy)

This is all I have on the R3350TC fluid coupling.
You can just barely see the fluid coupling.

Paul Lamar

The small diameter controllible pitch prop  would still suffer from
the high disk loading but would let you make full HP at static.
interesting thought - I will model the case (180 hp at 6000)
and put some rough numbers on it - Vance

Exactly. It will always suffer from high disk loading at low speed. So does
the UDF. The advantage is since you can control the pitch you can optimize
the pitch and get more power from the engine and therefore thrust. The UDF
used either two counter rotating fans or fixed stators behind a single fan
to recover some of the rotational momentum imparted to the air. A larger
prop with fewer blades will be more efficient at low speeds. If you can save
enough weight by going direct drive, plus some configuration advantages with
a small dia prop, and the variable pitch advantage, hopefully can help
offset the loss of efficiency. Remember this will only work on a high speed
single seat design. You certainly would not want it on a STOL plane.

An aircraft capable of using such an arrangement will need the following
numbers:

GW:                 1000 lbs
Max Cl:             1.8
S:                      46.6 ft^2
Flat Plate:         .8 to 1 ft^2

Monty

 
The AirCraft Rotary Engine NewsLetter.              Powered by Linux.
ACRE NL web site.
http://home.earthlink.net/~rotaryeng/            http://www.linux.org