I wondered that, too. Looking at the pic, it's a bit fuzzy, but it looks like there's a BT-20 motor tube sticking out, so I'm thinking C6-0, or maybe something vintage, if Bill has any B8-0's or B14-0's.

In fact, the lack of a strong 18mm booster, such as the B8 or B14, is why I built mine for using 24mm motors in the 1st stage. I think I've only ever flown it once, maybe twice, but the C11-0 got it off the rod with authority

As for the launch lug, I assume Bill just has it out of view of the camera

Doug

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