Supersonic 3D-printed rocket on a I280 Metalstorm, and wild recovery at sea

That’s a mighty big plume for an 18-inch tall rocket!

The golf-ball nose cone serves as the nose weight and self-centers on the airframe during launch. It is attached with a wire, and a blinking LED light (from REI for pet collars). Luckily it proves to be water-proof, as we lost the rocket at sea. We thought all was lost, but I got a voicemail at 11pm that night (I always put my name and cell phone number on the rocket):

“Steeeeve! Duuuude! How are you man? I was on a great date with Jill, and we saw this red light in the sea. So I stripped down and swam out there and got it. It’s this, this… I don’t know what it is, but it looks like a bong with a blinking light, and I’m sure there is a great story behind it. So give me a call at …”

And so we got it back! Photo below, and for more, here’s my talk on rocketry from Maker Faire which I just discovered online (the 3D-printing rocketry adventures start at minute 9:30).

Here are the 3D-print files, free on Thingaverse, for 38mm and 29mm minimum-diameter airframes. Total rocket cost is under $10, and total assembly time is about 10 minutes (after an overnight 3D print).

Here is a video of a supersonic launch with the same 38mm airframe. The J270 takes this puppy from 0 to 1,363 MPH (Mach 1.8) in 2.6 seconds, pulling 74g’s! According to RockSim, it topped out at 9,454 ft.