(Contributed - by Ray King - 08/01/10)
This is part 2 of the EMRR Challenge #7 as outlined I built this rocket as I wanted, making my
own modifications. I like the look of the rocket so I didnt modify that at all I focused on adding more
power. Tim the Tool Man Taylor would be proud if you dont understand this comment go watch
some reruns for Tool Time. This rocket is a Semi- version of the US Army Patriot Air Defense Missile. The rocket
is designed to use an 18mm engine and 12 recovery. I modified it so it now uses 2 -18mm engines and a
I followed the instructions with a few exceptions. First I made the engine mount a 2
engine (18mm) cluster with no engine hooks. The centering rings few made from hardened with epoxy. I also changed
the shock cord attachment, rather than using the standard Estes I ran Kevlar®
to the engine mount (drilled a small hole in the top and tied the cord around the engine tube assembly).
I also, added about .8 ounces of to ensure the rocket was stable. The rest of the assembly was per the
- 2 BT-60 White (6.625 Long)
- 1 - Yellow Body Tube (3.25 Long)
- 2 Blue 18mm Engine Tube
- 1 - (#72057)
- 2 - Body Tube Couplers
- 1 - 2.375 Long
- 1 - Std
- 1 - Green
- 2 - 2 Engine Centering Rings (Made from .060 Hard Balsa)
- Balsa Fins (3/32 Pre-cut Sheet)
- 36 of Kevlar®
- 18 1/8 Shock Cord
- 12 Plastic Parachute
- Decal Sheet
this case I didnt finish this because I ran out of time to get my review complete so I chose to fly this naked. I
did apply a couple of coats of Emerys Wood Putty thinned with water to the tube and fins prior to assembly to the
rocket. I found sanding these as components is a lot easier. My plan is to paint both rockets as the instructions
outline I will add some pictures of the painted versions to the flight log pictures.
I flew this rocket only once because the filed was a little small for the predicted. The maiden flight
was done on 2 C6-5s and did this rocket fly. Thankfully, I flew the single engine version first and was surprised
by the altitude of the C6-5 so I changed from the 18 parachute to the 12 parachute. On 2 C6-5s this
rocket screamed to very high altitude it took roughly 2.5 minutes until the rocket landed. I was going to fly 2
B64s but after the first flight they would only be a disappointment. I will fly this rocket again on a
bigger field once I paint it.
The recovery was ; it just took awhile for the rocket to land. Thankfully the wind was very light and the
rocket landed in the field.
If 1 engine = a Great Rocket; than 2 engine results in an even better rocket. For anyone who
likes high flying I would definitely recommend this modification and the 12 parachute is fine.