Gary-
Thanks for the explanation about Mohave Green not being sensible for 18mm.

Gary, here is a version 1 A3 (Original release) on the left and the revised A3, that has the case diameter nudged down. Note the difference in nozzle size which surprised me, later version being larger. Can you share what the design thinking was on this change?

The exit cone is surprisingly short so is under expanded. They might be slightly better off by increasing the expansion angle to >30 degrees, perhaps 45 degrees. Heck, make it a curved shape since it is SU ceramic!

I don’t think the throat on those has been changed, it may have used an older version of the tool or there could be a bit of ceramic “flashing” in the throat.

The nozzle expansion ratio is actually pretty close to optimum for the motor operating pressure, which is low by typical composite propellant model rocket motor standards.

Update
 

To update our progress on this project, we tested the delays for the C and D White Lightning Q-jets today and they were all within spec, with no failures or anomalies. The next step is to build the motors for certification and submit to the testing organization.

Awesome! That is great news. Is the White the same that is used in the F44?

No, it's the fast white that was used in the old G80FWL. These small motors need a relatively high mass flow rate to work with the minimum nozzle throat size of 0.090", so the igniter can be inserted.

Oooh thanks, I loved that G80FWL, still have one from Magnum, and an E30FWL also. These should be great, the flame in the test video looks great.

The only downside to these small motors is that the burn time is relatively short, like 0.7 seconds. Looking on the positive side they have great lifting capability!