Wednesday, September 05, 2012

Launch Report 2012-13

Location: Mattie Stepanek Park
Weather: 78 degrees and HUMID, wind 0++ mph, partly cloudy
Total flights: Today - (6); YTD - 80
Total motors: Today - 0; YTD - 95
Motors by class YTD: (Air -12); MicroHybrid -1; MMX -6; A -6; B -5; C -32; D -7; E -23; F -6; G -9 

Here is a description of the rockets that I flew today:
  1. The Rocket Formerly Known as 'Stretch' (TRFKS) - It was called 'Stretch' because it was longer than the other one I was flying.  It's been shortened but the goal is the same: To see if an ultra-loose nose will fall off and release a 'chute.
  2. Long Piston - A longish rocket with a 6" shock absorber section.
  3. Saturn V - Kit from Alaska Paper Model Works.
  4. Honest John - Also from Alaska Paper Model Works.
The flights:
  1. Saturn V @ 40 psi - I didn't have my launch support team so I had to hold the launcher and watch from underneath. I lost the rocket in the sun until I heard it fall on the pavement behind me. One fin was slightly bent but the nose was not :)
  2. TRFKS @ 50 psi - After 40 years of flying rockets, you'd think that I would have known the 'chute wouldn't deploy. 
  3. Saturn V @ 55 psi - I made sure I angled it away from the sun so I could see the whole flight. The good news is that the rocket doesn't separate right at launch.  The bad news is that it came apart at what appeared to be about half its potential altitude. I say this because it clearly slowed rapidly after separation.  It recovered nicely on the grass.
  4.  Honest John @ 60psi - The altitude wasn't that impressive considering this is the highest pressure that I've tried. I noticed that the launcher retains about 10psi of pressure and I'm wondering how efficient the sprinkler valve is. Filling to 60psi, even with a 10psi starting point took about 7 minutes.
  5. Long Piston @ 60psi - I also lost this one in the sun but the hang time was about 3 times as long as the Honest John. The nose was pushed about half way down on the pressure tube but the nose was nevertheless crunched. I pulled it back in place and turned the pump back on.
  6. Long Piston @ 60psi - Wow. I have no quantitative basis to estimate its altitude but I would say 3x the altitude of the Honest John was pretty close. It's clear to me that longer pressure tubes help performance.
I can't say that these are as fun as my motor-powered sport rockets but they do help quell my launch fever. Being able to launch 5 minutes from the house is a plus.