I’ve been neglecting this page. But I’ve still been busy! Here’s a catch-up:
I’m back on the fence about going to Airfest. I want to go, but a lot of minor reasons NOT to go have been cropping up; any one of them I could ignore, but piled together they’re making me feel as if I should reconsider. I have my COVID vaccination, but I’ll be traveling in areas where the vaccination rate is much lower than the area I live in. It was also announced that the fields east and west of the rocket pasture will have crops planted, which will make rocket recovery more difficult – especially the types of rockets I’m planning to fly this year (relatively small rockets that go high). Also, one of my friends from St. Louis is not going, and another is a maybe.
I’ve registered for the event, and I’m still preparing as if I intend to go. The weather may be the deciding factor…if we get to the week before the event and it is looking like it’ll either be rainy (like it was the last time I went, in 2019) or super hot (like it was almost every other year), I might just give it a miss and aim for Midwest Power in October.
Having said that…
Kerbal 5 is done! I need to finish rigging parachutes, but other than that it’s ready for the pad. I made a video of the ground testing.
I lost my mojo for Swamp Gas again. I’ll take another swing at it over the winter, maybe.
Gravity’s Just a Habit.
What I worked on instead was the two-stage Shapeshifter Jr. kit that I’ve been thinking about for a couple of years. It is nearing completion at this point, and should be ready to fly at Airfest, if I still go. It’s named after a lyric from an OK Go song.
Generally, I’ve been happy with the way this rocket has come together. I spent a lot of time working out how the interstage was going to work (see photos below). The interstage will carry an Altus Metrum EasyTimer to ignite the second stage, and will rely on motor ejection to deploy its parachute at its apogee. It should have enough space to carry a Jolly Logic Chute Release for that chute. The interstage also contains a BigRedBee radio transmitter for tracking. There’s a screw switch to power the electronics on, and a pin switch to safe the upper stage igniter (the igniter leads are shunted together while the pin is inserted, and connected to the pyro battery when the pin is pulled). A couple of weeks ago, I did some testing to figure out what kind of igniter would work best (spoiler alert: the Quickburst Twiggy in the photo will not work). Here’s a video of my testing.
The upper stage will use the same electronics sled as Kestrel, the 54mm minimum diameter rocket I flew in 2019 to 20,000 feet. It uses an Altus Metrum TeleMega, which combines the flight computer and GPS tracker into one device. My plan is for the booster to come down on a 36 inch Top Flight X-type parachute, and the sustainer to carry a 48 inch ultra-light Spherachute (this was the original parachute I bought for Kestrel and found to be too big). I’m planning two flights – an I285 staging to an I175 that should go to about 7500 feet, and a J425 staging to a J150 that should go to 13,500 feet.
- St. Louis Rocketry Association had a high-power launch in Elsberry – I just flew my LOC Nano-Magg but I signed off on three new level 1 certifications!
- I finally got Berthimus Prime repainted and re-vinyled after its repair a year and a half ago.
- I made another launch controller. I wanted to make a super bare-bones design that could be made cheaply. I also had an idea for making the launch controller in the form of a spool to make it easy to spool up the wire. The design I came up with can be made for about $20 in electrical parts, but you have to 3D print the case.
I’ll try not to make it six months between updates next time.