Finally launched the Harpoon!
Flawless launch at Midwest Power 10. Only real issue is I lost the fairing that covered my Go Pro camera, but that was actually by design. I was really worried the fairing would collapse and I would loose any good video. I had read about making an Adruino motion sensing switch on a blog at the University of Illinois Engineering website (my Alma Mater) a few years back and thought it would make an interesting solution to my issue. I built a few prototypes, and eventually settled on a design that would blow the fairing off the rocket if a photosensor detected returning laser radiation over a specific threshold. In the video below, you can see the fairing collapse right at 1:55), the Go Pro picking up the laser dot, then shortly afterward, the fairing is blown off the rocket by a small BP charge. Watching the landing from the ground, I was also a bit worried at the end that the rocket would land on a local farmhouse. Luckily, it missed by a few hundred feet.
The Harpoon has a very unique booster. I can reconfigure the rocket as necessary to fit any configuration of Motor’s I want within a 7.5” tube. Here’s a few photo’s to try and show how it works.
I’ll I have to do is make a new thrust plate, and centering rings to fly a completely different motor configuration. 100% of the motor thrust is transitioned to the bottom of the rocket, where it should be.
Next year The Harpoon will fly on one large 150MM center motor, and several smaller air starts for effect. In the meantime, most of my winter building will be on a super-secret new project……
Glad to see you got to flt the Harpoon Alex, can’t wait to see the big single motor flight!!
Tom
Tom,
thanks – you built a heck of a rocket, and I love the modular motor bay. I picked up both an O 25,000 and a P 8,000 last fall. Honestly, Ii ‘m not sure the harpoon can handle them. I’m currently planning on using the full scale Iris for the larger motors.