I was a bit surprised too, as the few gliders I have call for short delays too, but it makes sense when conditions are right. A less than perfect boost angle or some wind would still probably call for the shorter delay with the II. As a standard rocket example, I use a D12-5 on windless days for my demo flights with the 2.6" Goblin, but it needs a D12-3 if there's a breeze that noses it into the wind during coast. Both motors put ejection right at apogee, with the 5 seemingly hovering before ejection in no wind. Also, I wouldn't be surprised if the B6-4's average 3.68 second delay is a little shorter than it was back in the days of the original Skydart. Bill may be good at building light too.

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