My Level III Certification Launch


This bird was named "Half Mile Reality" and was not expected to reach that altitude. "Half Mile Reality" was designed to be a low and slow performer.

I read the Tripoli Rocketry Association Level III rules in March of 1997. I then wrote Bruce Lee and Phil Prior to ask them to be my TAP approving authorities for the design. I created my data packets and made multiple copies just in case Snail Mail got lost. they approved of the design and I was on my way.

I started building in earnest in June of 1997. I started purchasing materials at a number of local hardware and building supply stores. After 6 months of part time work into the winter I realized this was not the project that I imagined it would be. It ws an undertaking that only a patient wife could bear. I had my workbench in the living room of our apartment. I kept it clean for company and when I was not working on it. It also was a bit over estimate on the weight side.

When fully assembled and ready for fligh the rocket weighed 110 pounds. This was the all-up fully prepared and armed weight. I used an an Aerotech M-1939 reload.

After the flight it was prononunced "Crude but Effective" to quote Phil Prior at the March 28 - 29, 1999 Gouraj launch. The pictures displayed here are from the setup session, actual launch and from the my progress photos. I have to agree with Phil on the "Crude" description. I admit I did not take the time to make it pretty and smooth as many others have done. I was looking to keep it under 4000 feet with base drag and skin drag. I thought the more drag the better to keep it low instead of more weight in this case.

In the last stages before the launch I took the revised version down to Mechanicsburg to talk to Ross. Since noone was flying that February day Ray Forrester, Jim Rosson, Ross D. and others talked over the changes that could be made to my machine. I reworked the specs with Wrasp and VCP to change the CP without affecting the CG.

When project changes were finalized and ready to launch , Jeff Singleton and I headed down to the March 28 - 29 Gouraj launch. We hung around at Magnum until he could get my reload out of the magazine. I started prepping at the launch site at about 9:00 AM. I was not ready until at least 1:00 PM. What I learned in the assembly process will generate changes to make it easier next time. It took 6 people to walk the rocket to the pad comfortably. I prepped the ejection charge cannister did a final check on the charges and we then lifted the rocket to the vertical. When everyone was away I placed the igniter in the motor and moved away. Ray Halm was there taping the assembly and the launch preparations.

The launch itself was delayed because I did not see a continuity light on the hand grip. I tried to fire it anyway and the rocket just sat there. I checked the igniter wires and rewound them on the clips again. I checked the hand grip and I had a continuity light burning . Ross announced it and then we did a 5 count. "Half Mile Reality" jumped off the pad much to my surprise and kept on going. At about 200 feet I noticed a slight roll to the right. I know this would happen because the material the fins were made of took a slight set in storage. The flight was straight and true but a little more angled that I would have liked. It looked very good to see the ejection charges push out the three rocketman chutes and the nose cone on a separate chute. The landing was uneventful and slow.

When I arrived at the landing site, I couldn't hear any chirps from the altimeters. I was disappointed. It is unfortunate but the altimeters shut themselves off either when the ejection charges went off or when the package landed under parachute. I therefore have no idea of the altitude to which it really flew. Right now I am happy that the flight was completed successfully. Phil Prior took a quick look at the rocket and pronounced that the rocket passed muster. Phil signed the last page of my TRA tracking forms and I had my III rating. (Thanks, Phil). An exhilirating and successful flight.

As stated before "Half Mile Reality" was designed to be a low flyer. I used 12" ID Sonotube cut and fitted to make the 4 essential parts of the airframe. The four pieces were Nose Cone, Payload Section/Chute Compartment, Interstage Coupler and the Booster section. The booster section was designed in such a manner as to facilitate the removal of the fins through the body wall and to create a breakdown mode for transportation of the pieces. All of the airframe of "Half Mile Reality" fit in the back seat of a Pontiac Sunbird. The total length of the rocket was 10 feet 6 inches. The fin span was 36 inches fintip to fintip. Wrasp predicted 3400 feet at 110 pounds. The hard part was designing the fins to keep the CG/CP relationship correct. The original 24 inch chord and 12 inch span was making the CP move to far forward.

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Notice in the first picture how the rocket is seated on the pad. What I did not realize was that the launch rod was bent from the right to the left. See the next photo to see why I should have taken the tension off.

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The above photo shows me starting the rocket assembly. The first step was to get the booster section onto the sawhorses. I had carried my motor casing in the booster section to save space in the car. Jeff Singleton caught me taking out the motor casing.

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A fully assembled view of the "Half Mile Reality"

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Rear View of the test fit assembly of "Half Mile Reality"

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The First Iteration of "Half Mile Reality". The fins shown here were 24" at the root and 12 at the tip. In the final iteration the fins leading edges were moved back 3" to make the CP/CG relationship better and the new cone (the blue straight cone) was used to save weight.

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"Half Mile Reality" had to fit in the back seat and trunk of a Pontiac Sunbird. The booster was on the bottom in the back seat, the payload/chute section was then placed on top of it. The nose cone fit point first into the interstage and was then place on top of the payload section. The fins and other support equipment were placed in the trunk.

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Here I am during the Final Assembly. I am attaching the Sky Angle chute to the nose cone lines. In order to bring down the rocket more slowly I decided the nose cone should have it's own 'chute. I need not have been too concerned as the whole system came down gently. The rest of the rocket was suspended under 3 Rocketman R14C parachutes.

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A picture of the booster section during construction. Note the PML 4" tubing is still missing from the engine/fin mount. The line inside is the epoxy that holds the cut down sonotube into a "coupler".

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The Fin Cannister / Integrated motor mount. This fit into the 12" sonotube and became the mount point for the fins. The fin roots slide into the long channels and throught the tube wall to the engine mount tubing. A piece of aluminum angle was placed on either side if the fin root to allow fastening the fin firmly into the rocket.

Stadium Hardware, Builder's square, Smede Sons Builders Supply and HardQuarters were the sources of all my needs. Stadium Hardware in Ann Arbor is the most complete hardware store I have found in Ann Arbor. I have yet to send them a picture of what their products can do.

Thanks go to also Steve Lublecki for the photos of the launch pad setup crew and the actual launch. Jeff Singleton and I took the rest of them.


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