Jeff Spitzer wrote:

At 01:01 PM 3/16/99 -0800, you wrote:

The Predator is a high altitude UAV. That's Umanned Aerial Vehicle.
Used in Bosnia and Iraq. It is about the size of a 172.
All carbon fiber. 57,000 feet with a considerable payload
unlike the Aerovironment solar powered electric toy :-).

Paul Lamar

Paul, we should get you in our marketing dept.  Actually Predator has
a service ceiling of about 30K with a nearly stock 914.  Payload for
Predator is 450 lb.  The Altus is capable of 65,000 ft with 300 lb. but
with about $250,000 in custom stuff including custom (as in built from
scratch, not modified) sequential turbos and millions in development
specifically for high altitude.  Other nifty things needed for high alt
include dual intercoolers utilizing a recirculating EGW cooling system,
pressurized, constantly cooled fuel (to prevent boiling), custom designed
jet pumps in the fuel tanks to move the fuel to the pumps, variable flight
control gains due to low damping at alt, active thermal control of
avionics, etc, etc.  A fun project for sure.  BTW, the Aerovirnment "toy"
is an absolute engineering marvel and is capable of flying higher than any
gas powered toy will ever go (subsonic that is).  I have the utmost respect
and admiration for what they have accomplished.

That's great and politically correct in a corporate sense but it does'nt
carry 
anything. A good wind would blow it away and you would never see it
again 
with its 15 MPH cruising speed. Sorry! I think it is a waste of our tax
money.
 

P.S. The same vendor that produces our custom turbos has a triple turbo
package that can get a 914 to make 100 hp at 80,000 ft.  That's about 3:1
on the first stage and better than 4:1 on stages two and three.  Now if we
only had an airplane for that....

Jeff Spitzer

 
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