Eric Greenwell wrote in message ...
In article ,
says...
That price Ian gave and trust of 42 lbs. was before the motor was completed.
The ad even says available this fall. Its on Jet Cat USA web page, and its a
old ad. I have been in touch with the dealer and the price is about $3200 bucks
and the Jet Cat P200 now produces 50 lbs of thrust. There are several other
companys that make small Jet turbines, I have seen thrust ratings now at 150
lbs. which would be more than enough for self launch. The fin idea was thought
of, but remember that some of the thrust comes from the sucking action of the
motor. The exhaust is 660 C's. If you mount it like a motorglider engine it
will have to high enough so you don't burn your tail feathers off,

Or mount it on a metal Vee tail glider, like an HP-18.

For sustainer use (in-flight use only), vortex generators mounted on
the engine nacelle might mix enough slipstream air with the exhaust to
provide sufficient cooling.

if it drops
out of the belly, then self lauch could cause fob injestion. Shop around and go
out to a rc field where you can see and talk to the guys who have them.
Overhaul is now at 50 hrs. Thats only for inspection and maybe a bearing. No
big thing. 50 hrs is alot of time....about 600 climbs of 2500 ft.

Even for a self-launcher, that's about 5 years of flying, based on my
experience (200 hours a year, about 50 launches and 10 air restarts a
year).

Mounted on a
retractable pod boom with a arm that extends might be a idea. Food for though.
Tom

Even just fixed on a strut about 12" above the fuselage it would have
little effect on thermalling and speeds up to best L/D +10 knots or
so.

I would think that mounting a couple of small jets at or just behind
the wing/fuselage junction could also serve to remove some of the low
speed turbulence in that area. Also, if the engine had a tight
cowling around it then perhaps some water could be sprayed or drizzled
onto the outside of the engine and the resulting steam would mix with
the exhaust to provide some additional thrust. SWB Turbines in
Neenah, WI (SWBTurbines.com)has a Mamba turbojet which puts out 11
Lbs. of thrust. It is only 3.5 inches in diameter and would fit
nicely at the wing junction interface. SWB also has 45, 60 and a
100Lb thrust engine.