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Sky Rockets - Longspear 3

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JAL3

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The Longspear 3 actually began life as the Sky Longmarch 3, one of my earlier rockets. I remember not being impressed by much of anything except that it had a cool nosecone. After a couple of flights, the trifold and elastic parted ways and the nosecone drifted down US 87 towards Victoria on an overlarge chute and the body tumbled to the ground.

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JAL3

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Since it was one of my earlier rockets and getting fins straight was still a novel experience, I was not about to waste a perfectly servicable fin can. I concoted my own mod which I called the Longspear 3. It used the original body tube, 18" of BT20 and 18" of BT5.

The first few flights were fine but then something strange began to happen, sometimes. The rocket would boost to a few dowzen feet and then it seemed as if all thrust would stop and the nose would begin to rotate down and the rocket hung in the air. Momentum would generally carry it through about 270 degrees of arc so that it was horizontal and then the motor would "re-ignite" and the rocket would take off horizontally, leading to long walks and uncomfortable encounters with livestock. I thought the first time was a fluke, especially since it behaved fine the next time, and then it happened again.

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JAL3

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On its last outing, some time back, several of the tubes were damaged.

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JAL3

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My repair began with cutting out about 2" of damaged tube in the forwardmost BT5 section. A razor knife was used and the damaged part discarded. I will accept the shortening of the rocket.

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JAL3

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A 3" length of BT 5 was cut from my stock and then slit lengthwise. It was rolled, inserted into the BT5 which had just had the damaged part cut out and allowed to expand. A mark was then made at the overlap and the slit piece was removed. Another lengthwise slit was made at the overlap mark and the narrow piece of material discarded. This formed my coupler and it was glued in place with yellow glue and the 2 sections were rejoined.

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JAL3

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The rocket had also suffered from some buckling of the BT5 at the transition from BT5 to BT20. In this case, the glue joint to the transition was still good so the upper tubing had to be cut away.

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JAL3

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I just realized my previous post conflated the 2 transitions. Oops.:confused:

There was some buckling at the transition from the original body to the BT20 aw well. The BT was cut away from the shoulder and about 1.5" of tube was cut off. The remainder was then glued again to the shoulder.

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JAL3

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The blue areas were in need of some repainting after the splicing. I did not have the original blue I used so I masked a little bit wider area than I had done originally. I then used a piece of BT56 to hold the lower transition and began spraying blue.

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JAL3

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The masking was removed and the results, while not perfect, were good enough for me.

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JAL3

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The shock cord was then tied back to the lower transition and the rocket assembled. Its now ready to go.

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JAL3

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The Longspear finally got a chance to fly today after its repair job. It took off on a C6-3 and performed fine. The only real issue was keeping the upper assembly straight until liftoff. Some masking tape to tighten things up solved that problem.

A video of the flight can be seen here: http://www.flickr.com/photos/23694991@N03/3516520043/

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