LAUNCH! Schoolyard, November 21, 2010

I got up a little earlier than normal for a Sunday, why not launch a few before the winds pick up?

This is the Hot Rod Rockets BELL BOTTOM won on Ebay.

It's a conical stabilized model with streamer recovery. Great flight on a A3-4t engine.

It came back close enough I caught it before it hit the ground.

I made up a larger UP! CUP from a 16 oz. styrofoam cup.

I had great success with the earlier 13mm version, this one would fly with 18mm engines.

Look to the bottom left of the cup. I added too much clay to the lower end hoping it would lift the nose and "glide" down, lifting body style.

It didn't! After it left the rod with a B6-2 engine, it went horizontal. Landing about 100 feet away, there was no damage. It'll fly again, but without the clay weight on the tail end.

On a positive note, the engine ejected and the attached streamer did unfurl.
After two launches of the smaller 13mm UP! CUP there was soot and slight melting of the inside foam wall. On this larger cup the inside of the cup was coated with white glue to protect the foam from engine flash. That seemed to protect the inside wall. It wiped up clean with a damp paper towel.

On a sad note -

Here's that old Quest MMX igniter right after it's 14th launch!

I was going to use a 15th time today, but it broke when inserting the retention toothpick.

Here's the math -

14 uses X $.40 (per igniter) = $5.60 - $.40 (one time use) = $5.20 savings!

I subtracted the first, one time use of the igniter and only calculated the repeat uses and savings.

Gee, now I can afford those other more expensive igniters.

I'm using a six volt Estes controller with the MMX igniters. I would see more burn through if I had been running a 12 volt system.

The MMX SKYWRITER it's 14th flight on a Quest Micro Maxx engine. I also caught this one on recovery.

Also flown - The downscale GALAXY GUPPY and MICRO BIG BERTHA had successful flights on MMX engines.

The Micro Bertha should be rebuilt, next time for 13mm engines. It doesn't get the altitude to make it worthwhile using MMX engines.

TIP: A note on the Micro Bertha - Two years ago, Instead of Kevlar, I was using hemp shock cords. The hemp has held up very well after quite a few ejection charges. Hemp is cheap and works fine, it just isn't very pretty.

All five rockets (MMX, 13mm and 18mm engines) were launched using my surplus Quest Micro Maxx Q2 igniters! No pyrogen, just thin bare nichrome.