Jet Glider Sparrowhawk

Current Jet Cat turbines require propane to start them. The RC Jet guys at our
field have a whole bunch of Jet RC planes and fly from our field several days a
week. Including a FAA safety Inspector. The Jet Cat turbines due to using
propane for start, cannot be started inflight. The wind with blow out the
flame. Also, our RC guys do have flameouts everyso often requiring them to have
a dead stick landing. Jet-RPM of Sweden is making a Jet turbine, I have spoken
with him. His Jet Turbines will have a electric start, he hopefully will be
ready soon to start selling them. He said the price would be around 3450 euros,
this was several months ago. To prep a current Jet Cat for engine start does
take alittle time. I believe in March, in Lakeland, Florida the Jet RC people
are going to have a big meet. You might want to check it out. Jet RPM said
several sailplane manufactures have spoken to him already. It appears the small
turbine with a electric start could become a substainer with inflight start
very soon. Tom

Bob Kibby wrote:

My D-2T does not self launch. After an aero tow the D-2T handbook says 216
nm range based on sawtooth method at 882lbs gross weight, 3.43 gal of usable
fuel. I don't think that any current small jet engine approach can even
approach this. I think it will take a high bypass fan to compete with my
current and existing performance.

Two stroke engines are much more economical, for sure, but the turbine
_seems_ to promise a simpler, more reliable, more easily started system
and much less drag while the engine is out, especially interesting in an
engine failure situation. And there is the ability to cruise
significantly faster.

Any one need a copy of the Flight Manual
pages documenting this performance?

Nah, my ASH 26 E manual says I can go 290 nm on that much fuel, so I
believe you (I'm not sure I believe the manual, though!)

--
-----
change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

A Genesis owner in Sweden is planning to install one
or two jet engines which will pop out of the BRS hatch.
He's planning to use the electric start version which
is being developed. His progress can be monitored
on www.genesisflyers.com He has also done some wing
root fillet modifications and testing to improve low
speed air flow. Good pictures and descriptions.


At 05:06 14 January 2004, Tomnkeylargo wrote:
Current Jet Cat turbines require propane to start them.
The RC Jet guys at our
field have a whole bunch of Jet RC planes and fly from
our field several days a
week. Including a FAA safety Inspector. The Jet Cat
turbines due to using
propane for start, cannot be started inflight. The
wind with blow out the
flame. Also, our RC guys do have flameouts everyso
often requiring them to have
a dead stick landing. Jet-RPM of Sweden is making a
Jet turbine, I have spoken
with him. His Jet Turbines will have a electric start,
he hopefully will be
ready soon to start selling them. He said the price
would be around 3450 euros,
this was several months ago. To prep a current Jet
Cat for engine start does
take alittle time. I believe in March, in Lakeland,
Florida the Jet RC people
are going to have a big meet. You might want to check
it out. Jet RPM said
several sailplane manufactures have spoken to him already.
It appears the small
turbine with a electric start could become a substainer
with inflight start
very soon. Tom

Bob Kibby wrote:
My D-2T does not self launch. After an aero tow the D-2T handbook says 216
nm range based on sawtooth method at 882lbs gross weight, 3.43 gal of usable
fuel. I don't think that any current small jet engine approach can even
approach this. I think it will take a high bypass fan to compete with my
current and existing performance. Any one need a copy of the Flight Manual
pages documenting this performance?

Bob Kibby "2BK"

This turbine approach absolutely will not compare to the fuel
efficiency of a piston engine. Our point was simply that
fuel efficiency issues are dwarfed by the other advantages of
a turbine. Four times a small number is a small number.
If the turbine uses four times as much fuel (14 gallons in this
case) we are really talking about an additional 70 pounds/$20
of fuel, which we believe is a minor additional cost
compared to the other advantages a turbine provides.

This is clearly not true for ALL applications (if the 70# extra
means you are over gross and can't fly, then this kills the
whole idea). But on balance, for many cases, it looks like the
turbine idea, with it's fuel inefficiency, is interesting...

Mike Borgelt wrote:

When you do the performance calculation correctly you are in for a
surprise.

Jet engines have more power available the faster you go.

The downside of this is if the specs are for thrust in Newtons
available at a certain airspeed (not 0). At 0 airspeed, it
may be that the AMT-400 puts out significantly less power.
This would extend the takeoff roll some, and decrease efficiency
at any airspeed lower than "spec."

Or maybe the spec is for thrust on a test stand, who knows?

On 13 Jan 2004 10:55:44 -0700, (Mark James Boyd)
wrote:



www.usamt.com

In the specifications I also see a AT1500 engine that delivers 670 N @
75,000 rpm.
Should be more than enough thrust to modify my DDT into a DDJ ?

"Ruud Holswilder" wrote in message
...
On 13 Jan 2004 10:55:44 -0700, (Mark James Boyd)
wrote:



www.usamt.com

In the specifications I also see a AT1500 engine that delivers 670 N @
75,000 rpm.
Should be more than enough thrust to modify my DDT into a DDJ ?

If not, you can add the afterburner! (re-heat)

Bill Daniels

Early models of the KC-135 tanker used water injection
on takeoff for added thrust. No idea how much additional
thrust could be gained by adding this to a 45Lb thrust
turbine but it wouldn't increase fuel consumption the
way an afterburner would. How about a cowling around
the jet and water could be sprayed or misted onto the
exhaust section. Could the steam then mix with the
exhaust well enough to increase thrust or would it
be a perpetual motion add on?

If not, you can add the afterburner! (re-heat)

Bill Daniels

The water was injected into the combustion chamber, not the exhaust.
Evaporation increased the pressure in the chamber without increasing
temperature too much. In the 70's, there has been a spectacular accident of
a Lockheed Tristar outbound Hamburg where the mechanics put fuel ino the
according tanks instead of water - resulting in all three engines failing
during the initial climb, and the aircraft passing underneath a bridge of a
local highway. Partially passing, that is :-(

--
Bert Willing

ASW20 "TW"


"Steve Davis" a écrit dans le message
de ...
Early models of the KC-135 tanker used water injection
on takeoff for added thrust. No idea how much additional
thrust could be gained by adding this to a 45Lb thrust
turbine but it wouldn't increase fuel consumption the
way an afterburner would. How about a cowling around
the jet and water could be sprayed or misted onto the
exhaust section. Could the steam then mix with the
exhaust well enough to increase thrust or would it
be a perpetual motion add on?

If not, you can add the afterburner! (re-heat)

Bill Daniels

I had no appreciation for how much water was injected until I saw the fire
go out in a KC-135 engine one day when they hit the water after throttle up.
Quite a splash.

Frank Whiteley

"Bert Willing" wrote in
message ...
The water was injected into the combustion chamber, not the exhaust.
Evaporation increased the pressure in the chamber without increasing
temperature too much. In the 70's, there has been a spectacular accident
of
a Lockheed Tristar outbound Hamburg where the mechanics put fuel ino the
according tanks instead of water - resulting in all three engines failing
during the initial climb, and the aircraft passing underneath a bridge of
a
local highway. Partially passing, that is :-(

--
Bert Willing

ASW20 "TW"


"Steve Davis" a écrit dans le
message
de ...
Early models of the KC-135 tanker used water injection
on takeoff for added thrust. No idea how much additional
thrust could be gained by adding this to a 45Lb thrust
turbine but it wouldn't increase fuel consumption the
way an afterburner would. How about a cowling around
the jet and water could be sprayed or misted onto the
exhaust section. Could the steam then mix with the
exhaust well enough to increase thrust or would it
be a perpetual motion add on?

If not, you can add the afterburner! (re-heat)

Bill Daniels