Found Collection

I did not go to Springfest planning on flying any hybrids but
after I got to talking to Korey Kline of Hypertek, he indicated
he would provide the motor for a flight in one our VB Extreme 54
kits.  I also did not bring an Extreme with me so I borrowed Mike
Rodgers.  Korey drilled a hole for the N20 vent and installed the
motor while I prepped the payload with an Adept ALT2SA altimeter
with a 1 gram Robbie's Rocket charge.  Mike and Korey set up the
rocket on one of the pads equipped with a Hypertek filling
station.  It was a great flight with ejection right at apogee.
This flight did not have the pulsing sound normally associated
with the hybrid, probably due to the long burn injector installed.
After recovery we noted that the airframe kinked slightly above
the motor on impact.  We used the 28" parachute provided with the
54 Extreme kit and it came down hard with the spent hybrid in it.

After this flight, Ed Lacroix of Aerotech approached me and said
they would like to fly the Aerotech Hybrid in the same rocket.
Ed provided a 54mm coupler and I cut the kink out from the last
flight.  We CA'd the airframe back together, loaded the motor,
installed another ejection charge, and it was ready to go again.
I carried it out to a pad equipped with a 7/16" rod and told the
LCO to launch it on Ed's signal (he was concerned about wind gusts).
Another great flight with nominal recovery due to a larger parachute
installed this time.

Flight Statistics:
        Hypertek        J140    800NS           5960'
        Aerotech        I123    600NS           4364'

Observations:
        Of a total of 9 hybrid flights at Springfest (8 - Hypertek,
        1 - Aerotech), only 4 recovered under parachute.  While
        some of the failures could be attributed to mechanical
        acceration switches being confused by the pulsing of the
        hybrid, this shows an area that needs improving before the
        hybrids become accepted.

        It should also be noted that in the ballistic recoverys (some
        quite impressive) none of the motors were damaged.

        Although I am not a participent in either beta program, I have
        now flown both hybrid systems.  Each system has unique pros and
        cons and it would be hard for me to choose one over the other
        at this time.

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   Vaughn Brothers Rocketry - R&D               TRA: 1830  NAR: 23248

Stefan

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Do 't tou h the f op ydi ks su f ce!

Hypertek
        Pros - Simplicity,***on the fuel cartridge, install the motor,
               load the rocket on the pad/filling station, fill N20 tank,
               and launch.

               Lighter spent weight.

        Cons - Dedicated pad/filling station (this could be a pro in
               disguise if the wait is long for a standard pad).

               Requires N20 vent.  Easy on the minimum diameter rocket
               we flew (3/16" hole in airframe), however on some designs
               it could be more difficult.

Aerotech
        Pros - Once the motor is assembled and filled it can be handled
               like a standard composite motor.

               Already owned RMS hardware investment can be leveraged into
               hybrid technology.

        Cons - The pyro ignition material will require hazmat shipping fees
               to paid on reload kits.

This has not been a complete comparison of the two systems, just some of my
initial impressions after flying both.

The pros/cons of hybrids in general has been discussed at length in other
threads but one thing I havn't seen mentioned is the fact that there is
no tracking smoke.   After the motor burns out, it just disappears until
ejection (if you added tracking powder).

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   Vaughn Brothers Rocketry - R&D               TRA: 1830  NAR: 23248

1. Boost performance
2. Mass fraction
3. Recovery damage limitation
4. Initial shipping and manufacturing costs

I would think the "leverage" of reloadable motor hardware to hybrids is a
marketing scheme (in the neutral/positive sense) to lock in existing RMS
customers to the latecomer AT hybrid line.

Jerry

It does seem to have those flight advantages, but it seems the AT system
allows for staging, and easier pre-flight prep.  Their valving/igntion
system also seems to make for easier flights.

RE: Use of existing hardware.

Seems to me a good decision for any number of reasons from the
manufacturer to the end user.