Saturday, February 7, 2009

Launch Report #19: A sacrifice to the rocket gods

Today was the warmest day so far of the year - 48°, and less than 2" of snow on the ground. It, unfortunately, turned out to be a crappy day for rocketry.

I used my new 6V battery for all launches. It worked great, but I need to get a new light bulb for it.
First was the body of Frankenstein on an A8-3 carrying an SR-71 nose cone modified to be a lifting body It rose about 30 or 40 feet, burnt out, fell back to the snow, hesitated a second, then spit out the motor upon ejection. Nothing was damaged. I'll make an 18" long booster for the lifting body with extra-large fins.

Frankenstein, however, has a date with death. As part of a deal with a friend, it'll be launched into oblivion on either a C6-0/C6-7 or D12-0/C6-7 combo, with the entire forward body tube full of pink tracking powder. I hope to launch it high enough to never see it again but still see the brightly-colored cloud.

Next came Rama on a C6-3:

This picture, excellently taken by my dad, looks good, but it arced over starting during thrust (heavy rocket + 10 mph winds + underpowered fatass = disaster) as ejected just before impact. Nothing was damaged, but now I'll either convert it to a 24mm mount, try a D21-4, or only launch it in very calm conditions.

Here's me loading Alexi Leonov:

A few things to be seen in the photo: using a towel as a working surface for winter rocketry, the extension cord 'plugged in' to the 6V lantern battery, and SS1 sitting on the lid of the copy paper box I use to transport rockets.

Fly me to the moon...


Here's Alexi Leonov taking off on a B6-0. Unfortunately, I forgot to insert the second stage motor.....
Fortunately, the booster motor kicked the booster stage off, pushed the nose cone off the sustainer, and kicked the chute out so both pieces came down safely. Inside the payload bay was a sonic finder consisting of a beeper from an old motherboard and a 3V battery.

On its second flight of the day on a C6-0 / A8-5 combo:

That was the one perfect flight of the day. Ejection was just past, and both parts touched down safely although the chute didn't deploy. The upper stage motor mount was fried by the two booster motors and must be replaced before it can fly again.

Finally came SpaceShipOne on a C6-3. Forgetting how light it is and how high it goes on a C, I stuffed a 24" homemade chute in it. Ejection was perfect; it fell for a few seconds before the chute deployed and then away it went. It drifted forever on the 24" chute - across the field, over the street, and into a tree, 60 feet up.

I can't climb the tree or use a ladder, and both shotgun recovery (shoot the branch off the tree) and chainsaw recovery (chop down the tree) aren't gonna happen in someone else's yard, it's stuck for now. The rubber band shock cord will break in a few weeks, so I can hope to get the plastic tail cone and nose cone back at least; by then the body tube, motor mount, and fins will be mush or warped beyond repair. The string plastic parachute and cotton shroud lines might stay up for months or years.

The homeowners weren't home, so I didn't go too close to look, but it looks to be well-tangled. I'll stop by tomorrow and either leave a note or talk to the homeowners. This was my first sacrifice to the rocket-eating trees (previously the digester of Charlie Brown's kite); everything else has either come back safely or crashed.


Total damage of the day: 1 crashed but undamaged, 1 crashed, slightly crumpled, and way underpowered, 1 with a charred MMT, and one in a fine tall fucking oak tree.


Current totals: 375.12 Ns (14.1% I) total, 70 flights on 82 motors, 4.57 Ns (82.8% B) per motor and 5.36 (7.2% C) per flight.


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1 comment:

NICK said...

Very nice pics... would you send the highest resolution to me for consideration in the 2010 EMRR Calendar?