Don't Debate This, Too (final edit) - CTI N5800 in a Carbon Fiber Reinforced Composite Case
We successfully launched at 1:30 PM PT on Friday 21 September 2018 in Black Rock Desert Nevada. While only a portion of the on-board avionics was recovered, the evidence suggests the rocket made it at least 90,000 ft AGL. Please see my post on the Ausrocketry.com forum for more information. My uncle and I were safely waiting about 3,000 feet away when the rocket was launched and rapidly climbed out of sight into the clear blue sky. Other than a slight angle, which was likely attributed to the pad shifting during motor ignition, the boost looked perfectly straight. I was very relieved to hear nothing but positive sounds during the boost, and a somewhat sporadic but consistent set of tracking signals from the onboard avionics indicated the rocket had survived. The hardest part of this project, keeping my first composite motor case together during a Mach ~4 ascent, was validated quickly and gave me a lot to be grateful for. Finding the rocket turned out to be the hardest part of the trip... As it climbed, we tracked the rocket to about 68,000 feet MSL where it was still climbing and was at a range of about 2.3 miles to the East-Northeast. I continued to receive medium-strong signals from the onboard trackers but temporarily lost the GPS data packets. GPS data was required later, when the rocket was descending, at approximately 33,000 feet MSL, at a range of over 5 miles also East-Northeast. Packets came through until the rocket was about 1,500 feet AGL, at a range of over 7.2 miles. The last reported packet was in a very very difficult to access area. The GPS location and time stamps indicated a rapid descent. The entire flight was over in 3-4 minutes, which mean that the rocket fell very very fast, but not fast enough to not receive the last GPS packet about 1,500 feet off the surface. My gut told me that the rocket had come in semi-ballistic, but there were decent arguments to be made for a tangled recovery system. Nonetheless, the only way to find out was to find the rocket, or what was left of it. My biggest concern was not finding anything at all and/or not getting close to the last reported position. Fear of not knowing what happened far outweighed just about any other scenario... It took us the following two days and four attempts to finally locate the rocket. The first two attempts, immediately following the launch were direct line of site drives from the launch location but were quickly hindered by massive mounds of playa and deep gullies. On Saturday, we planned an early drive away and around the difficult to access parts. I tried my best with my truck, but received warning lights on Saturday and became concerned about ground clearance and getting stuck miles into the desert without a reliable means to contact anyone. The fourth attempt was aided by a local ex-US Marine who drives a Hummer H1 and tows a Polaris General for hunting rockets. With the right tools, you can do anything ... and we drove in a straight 7-mile line ENE from camp, hardly every turning the wheel. It was a tremendously fun, and rewarding ride in the Polaris. We began a search grid about 9 miles from the launch location, working our way back, but saw nothing until we drove directly under the last reported position. A few fresh clumps of playa dirt on the surface, zeroed us in on the resting place of the rocket. We dug down by hand and found the back of the back of the rocket, in-tact and about 1.5-2ft below the surface. The aluminum tip and about 10 feet of Kevlar shock cord were laying on the surface. We pulled pretty hard on the Kevlar with the shock cord but were unable to get the rocket to budget. Unfortunately, the Polaris's winch wasn't working and we couldn't pull at a great angle to extract the rocket. In the end, we ran out of time due to our schedules and had to haul ass out of there. I brought the tip with me, which includes the thermocouple logger. I was able to get enough data from the logger and piece together what I think happened. While it sucks to have suffered a ballistic descent, I am very encouraged by the successes we had during this flight. Based on all the information I have right now, I believe drogue parachute became detached sometime after the apogee ejection charges fired and the rocket, which was falling nose down, with the tip/shockcord off to the side, hit the ground. My gut is that it happened when the charges fired and ripped off, or as the rocket fell rapidly and began to hit thicker air and shredded. Check out my thread on the Ausrocketry forum to learn more about the project and the estimated altitude it may have achieved. (https://forum.ausrocketry.com/viewtopic.php?f=6&t=6119)
Author Mike Passaretti
Duration 219 seconds

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