Before we get into the weekend of the regular Tripoli East NC December launch at Bayboro, we need to go back two weekends to Saturday, November 28, the weekend after the regular November launch. The back story is that a team of NCSU graduate students, led by Chris Buck, a former president of the NC State High Power Rocketry Club, have been designing and building a pair of “cube-sats” to acquire information in a project they call HATI, or “high altitiude tethered instrumentation.” They wanted to deploy this instrumentation package at about 12,000 feet to kick the package out, and gather data all the way down to the point where each of the 2 would put out a small parachutes and land softly. I conferred with them and Jim Livingston, and we hit upon the plan of flying my Spork on a 4-grain 115mm N motor and completely redesigning the forward parachute compartment to hold and deploy the scientific package, and moving the main parachute and its associated gear to the compartment aft of the electronics compartment, where the apogee deployment gear usually rides. We could not get the project ready in time for the November 21-22 weekend, so I agreed to open the range for a special launch on the next weekend. The NCSU High Power Rocketry club also decided to come along and do a shake-down flight of their sub-scale model for the NASA competition.
Chuck Hall came along to assist with the project, and we decided that it would be a shame to drive all the way to Bayboro when the waiver was open, and just stand around and watch somebody else fly a rocket, so we had some fun of our own. Chuck flew his 4” Patriot on an Aerotech J420R. All components worked perfectly and the rocket came back safe and fairly close. I loaded my Astro*Mollusk VI with a 4-grain 54mm K motor (homemede) and made another great flight to the 5800’ region. The HPR team had a pair of extra channels on their Arduino for data collection, and a few thermocouples around the lab, so we hatched a scheme to record surface motor casing temperature on the front and back ends of a 38mm homemade I motor. I haven’t seen the temperature data yet, but the flight was essentially perfect.
When it came time for final assembly of the Spork 2.0, I let the team down in a big way. The motor/forward bulkhead combination would not fit in the rocket, and no reliable work-around could be found. We came back home to re-group and re-fit.
Fast forward to December 19-20…
The weather forecast for this weekend was just about perfect (for December) and turned out to be very fine. Saturday was a little windy, but the wind was in exactly the right direction (out of the northwest) and 12 flights were made – or attempted. A couple of young tads from Tommy Harrell’s extended clan were on hand and made a pair of flights. Allen Harrell flew his Cow Cow w/ Awesome Astronaut on a C6, while Issaiah Harrell flew the Hobbes rocket on an F44. I was busy with my attention elsewhere, but I think both flights went well.
One of the NCSU senior design class teams was on hand to fly the rocket called Eruca on another shakedown flight, this one designed to get the team familiar with the use of altimeters for 2-stage deployment.
Dennis Hill brought back the venerable Tiberius to fly it on one of the new Aerotech RMS loads, the K535. This load came from the factory with an external thrust-ring that was glued on in an orientation that could only be described as “wonky”. Dennis did some gluing and some taping and worked the whole assembly into a very squared-up arrangement, and when we pushed the button, everything behaved perfectly.
It was finally time for the Spork 2.0 with its payload to get loaded and launched. We assembled everything and applied the requisite duct tape repairs, loaded the rocket at the away cell and pushed the button. The N motor rapidly pushed the whole package straight and fast up to the edge of the subsonic/transonic range, about 4 seconds into the motor burn, when the rocket folded up and tore itself into little pieces. There was a sparkly rain of carbon fiber, fiberglass, and 3D printed plastic shards that fell over a fairly large area. What a mess. Most of the largest pieces were recovered: The cube-sats were found – somewhat warped but still beeping, the parachute was recovered intact, the motor casing only had a few dings on it, both altimeters were still beeping, and the radio tracking transmitter was recovered with the antenna sheared off [on Sunday!]. Beyond those components, everything else is going to need to be re-built before the Spork 2.0 flies again. Graduate education is not for the timid or faint-of-heart.
Sunday was even finer! The wind calmed down a lot and only one rocket left the property. The motor use summary table shows the typical Sunday anomaly:
Wait! I haven’t put in the famous motor use summary , yet. Here it is…
Notice the big gap between C motors and H motors on Sunday. A complete absence of “mid-power” motors. That was perfectly alright with the crowd, everybody seemed to have a good time.
Justin Giulak did most of the low-power flying, with several flights in the A, B and C range. Chris Aubright came back to Bayboro for one last launch before he is posted to the NAS in Jacksonville, Florida. He flew his level 3 rocket, the Liberator, on an Aerotech K550W for a beautiful flight up to the 5000 foot range.
Dave Morey seems to keep finding these commercial motors that I have never heard of, and this month was no exception. Dave launched the Upscale Arreaux on an Aerotech J740G staging to a CTI J94 Mellow. The flight was a great success and the J94 seemed to burn forever. Chuck Hall flew his Patriot on an Aerotech J420R motor and recovered it close to the launch pads.
C.J .Lucas brought out his recently-finished Eagle Claw 4 and launched it on an Aerotech J500G for a perfect 2-stage recovery flight.
One of the first flights of the day was Jeff Goldstein’s Red Darter, flown on an AMW J475. This little rocket did some extreme “darting” and ended up landing in the wooded area to the northeast of the launch site. Jeff and Chris Aubright got in the car with the Big Red Bee receiver and disappeared for most of the day. I was just beginning to worry about them, when they rolled up with the rocket intact. The rocket missed the trees and was lying on a dirt road back beyond the power lines. Once again, a radio tracker device pays for itself many times over.
Dave Morey captured a few videos from Sunday’s events on his photo-sharing site.
Join us in January if you can, and please try to find some time to help us out at the Astronomy Days exhibition January 30-31, 2016.
Prefect, Tripoli East NC