Test 2019-2

This was my first flight with "Everclear". After the 2-grain test stand run, a quick Burnsim session suggested a 4-grain configuration with #32 nozzle could work.

4 grain 54mm Everclear motor with #32'ish nozzle (some crud in the throat from previous use, largest diameter maybe 0.549"?), using one 45-cal pyrodex pellet on an e-match for ignition. Flown at NCR North shortly after Jamie Weiss flew her successful L3 certification flight on 4 May 2019.

The grains used were from the 7 and 8 January 2019 batches:

• 8 Jan grain 1, 2.980" long, 162.6g gross, 5.48g casting tube, 157.12g net
• 8 Jan grain 2, 2.970" long, 162.0g gross, 5.46g casting tube, 156.54g net
• 7 Jan grain 3, 2.976" long, 163.4g gross, 5.48g casting tube, 157.92g net propellant
• 7 Jan grain 4, 2.650" long, 146.1g gross, 5.52g casting tube, 140.58g net propellant

The incomplete/short grain was put at the forward closure end, leaving a bit of a gap between the propellant and the closure.

Used abou 13.625" of ARR liner (if using the pressure tap closure, would have been 13.75, but we needed about 1/8" less to make the normal closure with o-ring against liner fit). Small profile o-rings were used between grains, leaving the grains still slightly "loose" in the case. The buna-n o-rings were lightly lubed, and the liner exterior was greased.

Results

PFND.

Forgot to get pre-flight masses. The post-flight mass of the airframe and motor was 4055g. That's complete except for maybe 3-5g in the ejection charges, and of course the propellant consumed.

Flight data in 2019-05-04-serial-1257-flight-0017.eeprom shows 6079 ft GPS apogee.