From: mckiou@cbnewse.cb.att.com (kevin.w.mckiou)
Subject: Re: Rocket Powered Gliders 
Organization: AT&T
Date: Wed, 18 Nov 1992 18:33:01 GMT

In article <1992Nov16.200518.15585@acuson.com> griffith@acuson.com (Paul Griffiths) writes:
>
>	Has anyone seen/heard/tried anything with regards to
>the rocket powered gliders?!  The boxes seem to suggest rocket
>assist takeoff to 1000 ft or so and hours of gliding enjoyment...
>I have quite a few hours of thermal soaring and am sorta tempted
>to give one a try, but something tells me I'd be getting way over
>my head..(no pun intended) Any comments?!
>			-Paul
>
I assume you are talking about the Estes AstroBlaster (AB).  I've flown
it and a few other RC Rocket Gliders (RCRG).  The AB box is a 
bit misleading.  There is no way you can boost it to 1000 feet
short of an F impulse motor (~80 newton-sec). A typical D impulse
motor (~20 ns) will boost it to about 200 feet.  Flight durations
are about 30 sec from that altitude.  The AB performs more like a
hot fighter plane than a sailplane.  We added a pair of "strap-ons"
to the tail of our AB to cluster 2 C6 motors with the main D11.
This gave it enough punch to move out quite respectably.  Alt was
about 400 feet.  Flight time ~ 1 min. It's great fun to launch this
way.  However, if you are looking for more flight time, take it
to the slope.  Also, Estes has added an adapter to the kit so you
can put an .049 pusher on the tail.  I hear it's a lot of fun to 
fly.

If you want a  truely high performance RCRG, buy the AeroTech Phoenix.
It is bigger (50" wing span), it will thermal, it is fully aerobatic
(rudder/elevator/aileron), and has an incredible speed range.  	If built
correctly, you can fly  very slow (~20 mph) or very fast (~160 mph).
The very fast is on boost with an F25 - most impressive 2 foot flame.
I probably have 300 flights on mine.  Most of those were off a high-start.
That's another advantage of the Phoenix.  You can get reasonable flights
off a high start.  One other thing.  The Phoenix is actually LESS
costly to fly with rocket motors than the AB.  The Phoenix uses F and
G impulse motors.  But the motor technology is reloadable.  The AB
uses expendable motors.  A 500' boost on a F13 reloadable costs $3.00,
retail.  A 500' boost on the AB would cost at least $5.33, retail
for 2 D11.  BTW, a 1000' boost of a Phoenix on a G12 reload costs
$5.00, retail.  Also, the reloadable motor  IS supplied with the kit.
Price is $189, retail.  I've seen it for ~$135 in local hobby shops.

There are another few kits on the market: Avatar and a scale Space Shuttle
(complete with strap-on boosters and main fuel tank) by NorthCoast
rocketry.  And, a new outfit called Hobby Lab has a MD-80 (like the
commercial jet airliner) and a F-14 swingwing.  The F-14 looks really
cool.  Wings swing out at the end of boost (~50" wing span) for a
nice glide.  Seem to remember it being a bit pricey ~$200.

Beyond these kits you must get into the world of competition RCRG
designs.  These are small birds (~40"-46" wing span) that will reach
400 feet on a D and >1000' on E impulse motors.  Some of the best of 
these tend to be pretty sophisticated designs - though the building 
methods are pretty standard for  high performance sailplanes.  These
birds boost and thermal beautifully.  They also fly off a high-start
and slope very nicely.

As to your fear of getting in over your head.  NONSENSE!  If you can
fly slope ships, RCRGs will be a piece of cake.

Kevin
Newsgroups: rec.models.rc