I did my first dual deploy flight this weekend, and have been combing over the onboard footage (120fps from a RunCam2 4k). Its a stock Apogee Katana on a J270W.
Three things from the video:
First, the video only goes up to a second or so before the main deploys, I think the shock from that ejection jostled the battery, others have mentioned similar problems with the runcam (https://www.rocketryforum.com/threads/acceleration-limit-of-camera-runcam2-troubles.156661/). I might look at soldering the battery on or otherwise better securing it.
Second, the nomex blanket seems to rip. That blanket didn't have a grommet, just a little reinforcing stitching. and I wasn't super careful about the way I tied it on, but I'm still kind of surprised by this. Looking at the frames, you can see there is some flame continuing to burn _inside_ the nomex after ejection, so I'm wondering if it burned.
Note the orange wires are ejection charge wires, not the shock cord, so by this picture it is already detached from the shock cord, but you can still see it illuminated from within:
And a few frames later you can see it fully detached, with what looks like a crescent shaped tear where it was tied on
The third strange thing (you may have already noticed) is that the backup ejection charge seems to go off at the right time (apogee+1), but it looks like the bare e-match sparking, without the powder! Or maybe just a little bit of powder. I had the charges in centrifuge tubes, extra space packed with dog barf and latched closed, but not taped or anything. Has anyone had primary charges "blowing apart" their backup charges? It seems like if this happened and the primary charge didn't work, it would have made both charges fail to work. Does that look like a correct reading of these frames?
Three things from the video:
First, the video only goes up to a second or so before the main deploys, I think the shock from that ejection jostled the battery, others have mentioned similar problems with the runcam (https://www.rocketryforum.com/threads/acceleration-limit-of-camera-runcam2-troubles.156661/). I might look at soldering the battery on or otherwise better securing it.
Second, the nomex blanket seems to rip. That blanket didn't have a grommet, just a little reinforcing stitching. and I wasn't super careful about the way I tied it on, but I'm still kind of surprised by this. Looking at the frames, you can see there is some flame continuing to burn _inside_ the nomex after ejection, so I'm wondering if it burned.
Note the orange wires are ejection charge wires, not the shock cord, so by this picture it is already detached from the shock cord, but you can still see it illuminated from within:And a few frames later you can see it fully detached, with what looks like a crescent shaped tear where it was tied onThe third strange thing (you may have already noticed) is that the backup ejection charge seems to go off at the right time (apogee+1), but it looks like the bare e-match sparking, without the powder! Or maybe just a little bit of powder. I had the charges in centrifuge tubes, extra space packed with dog barf and latched closed, but not taped or anything. Has anyone had primary charges "blowing apart" their backup charges? It seems like if this happened and the primary charge didn't work, it would have made both charges fail to work. Does that look like a correct reading of these frames?
