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Marty Weiser

December 3, 2003

Marty Weiser Rocketeer Profile – November 2003

I was involved in rocketry from about 1968 – 73 and then became a born again rocketeer (BAR) in either late ‘99 or early 2000 when I took my boys out to a SPARC launch after seeing one of the flyers posted by Kirk. We flew a couple of the models that had survived in my folks’ attic and we were hooked. Since then the rockets and motors have gotten bigger (I now have my Low Explosives User Permit – LEUP) so that I am now doing the design work on an M impulse rocket that I plan to use for NAR level 3 certification in the Spring of 2004. Along the way I had my arm twisted to become the SPARC VP in the fall of 2000 which evolved into my current role when the President decided to step down.

I bought my first mid-power rocket, a LOC Aura, from Ursula of AllHobbies at the SPARC launch in June 2000 and flew it in July. I then built a stretched version called the Blue Danube which I flew on an H128 motor for my NAR level 1 certification in October 2001. Over the winter I built a stretched version of the LOC Caliber to include an avionics bay which I named Caliber-X and flew for my level 2 certification in June 2001. The J350 motor drove the rocket to an estimated 4600 ft. and it drifted three quarters of a mile to the NE for recovery 30 ft. north of Wild Rose Rd.

My boys, Matt and John (pictured to the right with the Caliber-X in ‘01), attend almost every launch and really like hanging out with all of the neat people who attend SPARC launches - sometimes they even fly a few rockets. John’s favorite thing to do at the launches is to take long hikes with Bob in search of Bob’s min diameter mid-power flights that have a propensity to drift. Matt has decided he likes to upscale the Estes Mosquito and has built and co-flown a three diameter (6X) version on an I161 motor.

Since I wasn’t ready to get my LEUP after I earned my level 2 certification I decided to build some rockets that were not as conventional as my level 1 and 2 birds. The first of these was a standard size Estes Fatboy that was modified with a 38 mm motor mount. There were several structural modifications that were necessary to fit an 8” long motor into a 12” long rocket along with the parachute and nose weight required for stable flight, but the crowd reaction when they hear “Estes Fatboy on I161” is worth it. My next project is a short fat 4” rocket with a ring tail and an attitude when loaded with one of the larger 38 mm motors – Mama Raccoon is a natural name.

Last year I had decided to build either Papa (8”) or Bubba Raccoon (12”) for my level 3 certification, but a couple of things changed that. The first was Bob, Ray, and Keith’s report that someone had launched an upscale Astron Sprint on an M motor at Black Rock this year - a larger Raccoon would be very similar in appearance. The second was the successful launch of Skeeter Eater on a J570 motor this Fall (see Ray Stoner’s video of the flight in the launch photos area).

Skeeter Eater is a 12X upscale of the Estes Mosquito that came about through the receipt of a 6” diameter mailing tube at work and Matt’s interest in building the 3” Mosquito. It turns out that seven 38 mm motor mounts will fit in a 6” body tube with room for through the wall fin mounting. Once again I had to get creative in the construction department to make it all work – the fins are fiberglassed foam with plywood reinforcement to minimize the weight in the tail. I figure the same techniques can be scaled up to a 24X upscale (12” diameter) with a central 98 mm motor mount for an M1419 and six 54 mm motor mounts in case I want to load some long burn motors for air starts for flights after certification. Skeeter Eater Beater is still on the drawing board. Of course I still build some smaller rockets – seven 18 mm motors will just fit in a stock Fatboy as seen in the picture to the right.

I have had my share of setbacks along the way. I almost trashed Blue Danube in the shake down flight for my level 1 certification when I attached the parachute to the wrong eyebolt – the chute failed to deploy and the rocket landed in a flat spin. Luckily, I build strong rockets and the only damage was a few paint scratches so I my cert before winter. My favorite mid and small high power motors use the black jack propellant for relatively low, long thrust and lots of smoke. Unfortunately, they are hard to ignite and it is not uncommon to ignite the delay grain well before the motor lights. Both Mama Raccoon and the 38 mm Fatboy have ejected during boost as a result – the weighted nose cone of the Fatboy landed within 10 feet of me for a true heads up flight. However, the most spectacular failure to date was of Joseph – a joint project with Ray Stoner which was inspired by a 4.1” ID carpet tube. Such a tube will hold four 38 mm motor mounts. Joseph was designed for dual deployment since four J570 motors will reach over 10,000 ft. Unfortunately, we had not installed the avionics bay bulkhead for the shake down flight on a pair of J350 motors and the charges could not pressurize the entire 6 foot long body tube to deploy the chute. Luckily, the lawn dart of this 17 lb. rocket was in the middle of the field and nothing other than pride was hurt. Ray’s video if this flight is also posted on the SPARC site and we are rebuilding Joseph as a Lazarus (the avionics bulkhead is complete!). All of these failures have taught me that careful and thoughtful preparation is required in rocketry, particularly as the rockets become larger.

Posted by terry at December 3, 2003 4:30 PM

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