Scratch Superscale Ninja Original Design / Scratch Built

Scratch - Superscale Ninja {Scratch}

Contributed by Eric Speckman

Manufacturer: Scratch

Superscale Ninja
(Contributed - by Eric Speckman)  

[Rocket Pic]

For someone who is used to Estes kits, this thing is huge. For people in HPR, this isn't so big. This rocket stands 4' 9.4" tall, and is 4" in diameter. As of now, I don't know what the exact weight is, but I it is around 3 1/5 lbs (Loaded weight was 4.5 lbs). A lot of the weight is in the payload section. The heavy bulkhead and the 10 oz. PML nose cone add up to quite a lot. It has a 36" round chute from.

[Rocket Pic]It has a 29mm motor mount tube, and I built a booster pod for it. It consists of a ring of 8 24mm engine tubes glued to the inside of a coupler. For a picture or the back of the loaded rocket, click here. My original idea (Which changed) was the following: It will have a timer to air start the main G64 Aerotech reload. The flight plan is as follows (hopefully): Ignition of the 8 D11-P's with a car battery. At a either .5 or 1 second, the timer (or thermalite) ignites the G64, and boosts it higher. The main motor's ejection will hopefully deploy the chute. If the main motor doesn't light, the timer will ignite an ejection charge, and push the chute out. It better fly right, or I will have a lot of work to do!

[Rocket Pic]Flight #1: (1)H180 + (8)D11's

The Ninja flew for the first time on July 20, 1997. After talking to some people, I decided that boosting on the D's and airstarting the G was a bad idea because composites are harder to light. So I needed a more powerful engine. An announcement was made asking if anyone could help me, and Frank Noble was willing to help me with my project. I ran a computer altitude sim, and found that an H140 SU would work, but the motor dealer did not have any. So, I was able to borrow a reload casing, and fly it on an H180. Frank loaded the motor, and explained how to drill the delay to the right length. He showed me how to use teflon tubes and thermalite to ignite the D11's.

[Rocket Pic]Finally, it was ready to fly. We took it out to the pads, and set it up on pad 5. The rocket was angled a little bit away from the spectators (and downwind) for safety. When if finally came time to launch, the LCO made everyone stand up and watch this rocket, and it was a very heads up flight. 5...4...3...2...1...Launch... The H lit after a short delay. It boosted straight up on a column of smoke. Just after the H burned out, the D's lit for a little extra smoke and noise. After it coasted for 9 seconds, and the ejection went off and the chute came out. It took a little while for the chute to open, but it deployed after a second or two. It drifted for a long way, and was recovered undamaged. When I recovered the rocket, I quickly looked, and it appeared that all engines ignited. Later, it was pointed out to me that only 6 of the 8 lit, but it was still spectacular.

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