Aerotech Astrobee D on an "H"?

[10 count]

Any probelms using this rocket for a Level I certification flight
(Aerotech H97 reload)?

Thanks.

[Bob Kaplow]

In article <7q9qvtc44k75a53m0...@4ax.com>, 10 count <spa...@testor.org> writes:
> Any probelms using this rocket for a Level I certification flight
> (Aerotech H97 reload)?

There shouldn't be. but I'd suggest an H128 instead of an H97. Easier to
ignite, quicker thrust buildup, and less total impulse.

Bob Kaplow NAR # 18L TRA # "Ctrl-Alt-Del"

Kaplow Klips & Baffle: http://www.nira.chicago.il.us/Leading_Edge/MayJun00.pdf
NIRA: http://www.nira.chicago.il.us NAR: http://www.nar.org

This is a country which stands tallest in troubled times, a country
that clings to fundamental principles, cherishes its constitutional
heritage, and rejects simple solutions that compromise the values
that lie at the roots of our democratic system. -- Supreme Court
Justice Thurgood Marshall, 1972

26-October, 2001: A day that will live in infamy
Support Freedom: http://www.indefenseoffreedom.org/

[10 count]

On 22 Nov 2001 10:30:46 -0600, kapl...@eisner.encompasserve.org.mars
(Bob Kaplow) wrote:

>>In article <7q9qvtc44k75a53m0...@4ax.com>, 10 count <spa...@testor.org> writes:
>>> Any probelms using this rocket for a Level I certification flight
>>> (Aerotech H97 reload)?
>>
>>There shouldn't be. but I'd suggest an H128 instead of an H97. Easier to
>>ignite, quicker thrust buildup, and less total impulse.

All I have are H97's for now and the certification is next week. Will
the H97 have too much impulse?

[Ray C]

On Thu, 22 Nov 2001 10:27:49 -0600, 10 count <spa...@testor.org>
wrote:

>Any probelms using this rocket for a Level I certification flight
>(Aerotech H97 reload)?
>
>Thanks.

I used an A-Tech Astrobee D on an H-180 for a level 1. It was
slightly built up with 4 plywood centering rings and a single 4 foot
'chute/tubular nylon shock cord. The same rocket flew extremely well
on an H-128-10 with deployment at apogee. In neither case was there
an damage upon landing.
Remove "123" from e-mail to get actual address

[Steve Gibbings]

H97 is Black Jack propellant, which may be harder to light than a White
Lightening. It has 200Ns total impulse
H128 is White Lightening, which is very easy to light (compared to Black
Jack). It has 175Ns total impulse

The H97 will put less stress on the airframe but has a longer burn time,
you'll get a higher altitude than with a H128 given "average" rocket weight.

I'd agree with Bob and go for a H128, especially if it is windy, but
there's nothing wrong with the H97. Run a simulation (RockSim or RASP) and
you'll see the difference in performance yourself. You can then make an
educated decision.

Steve.

"10 count" <spa...@testor.org> wrote in message
news:0haqvt8v98jojgfp5...@4ax.com...

[Bob Kaplow]

In article <0haqvt8v98jojgfp5...@4ax.com>, 10 count <spa...@testor.org> writes:
> All I have are H97's for now and the certification is next week. Will
> the H97 have too much impulse?

How do you have H97s (plural?) when you aren't certified yet?

Probably not. Be real careful with BJ motors if there is any wind at all.

Bob Kaplow NAR # 18L TRA # "Ctrl-Alt-Del"

Kaplow Klips & Baffle: http://www.nira.chicago.il.us/Leading_Edge/MayJun00.pdf
NIRA: http://www.nira.chicago.il.us NAR: http://www.nar.org

Timid men prefer the calm of despotism to the boisterous sea of
liberty. -- Thomas Jefferson

[10 count]

On 23 Nov 2001 08:28:29 -0600, kapl...@eisner.encompasserve.org.mars
(Bob Kaplow) wrote:

>>How do you have H97s (plural?) when you aren't certified yet?

The guy giving me the certification has them and is bringing them to
the event.

[Carl Battles]

Good Answer!!
CB

"10 count" <spa...@testor.org> wrote in message

news:klosvtctj2237b7nv...@4ax.com...

[Larry S. Zeilmann]

I flew a successful level 1 flight earlier this month with an Aerotech
Astrobee D on an H128-10. I made a few modifications in the engine mount
area. I left out the thrust ring and retainer clip. Glued the aft centering
ring to the face of a .125" plywood centering ring. Then went with the usual
T-nut & clip positive retention system.

I stayed with the dual chute but I didn't permanently install the main body
tube coupler. Instead I hold it in place with three through the wall nylon
screws. Secured with nylon nuts epoxied in place on the inside wall of the
coupler. This modification was so that I could later remove the it to build
an altimeter bay inside the coupler. At that time I will then use dual
deployment with drogue deploying from lower body and main from upper body.
Since the upper body will eventually be used to deploy the main chute, I
didn't want to glue the nose cone on per the instructions. Therefore, my
nose cone is held in place with three small brass screws. I also drilled a
.125" vent hole covertly located in both the upper and lower bodies.

I Used RockSim 5.02 biased to the actual mass and CG to simulate the
Astrobee D on about every HPR motor possible. My launch weight with the H128
was 40 oz, (1135g). Peak Altitude was estimated at 1975 feet, Max
Acceleration of 456 ft/sec. Deployment was at apogee with nose down. Both
chutes tracked right next to each other and were evenly rated at 18fps
descent rate.

I was happy with the flight except for one item. I launched off of a Mantis
.25" rod, and the Astrobee did deviate slightly from vertical upon leaving
the rod end. I am suspicious that rod whip might of caused this, but not
sure. I will install a set of buttons for the next flight and fly it off a
rail.

Good luck and hope things go good for you!

Larry

"10 count" <spa...@testor.org> wrote in message

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