I have joined the “it was stable for the last 112 flights so what just happened??” Q-Jet club. I put my current Nova Payloader up for its 111th, 112th and 113th flights today. The first of these was on an Estes C6-5 and was as expected. The next was on a Q-Jet C12-6FJ. Also as expected. Then I put in a C18-6W. It chuffed quickly, then about 30 or 40 feet up did a skywriter routine for a bit, before shooting off at about a 40 degree angle upward. It got high enough that with a shorter than advertised delay (~4.3s, per the FS Mini aboard) the ‘chute got out before it lawn darted and the model was pretty much unscathed. But still…what the heck??!? I have flown hundreds of Q-Jets and dozens of C18s and D20s, and this is the first time this has happened to me.
I will admit I didn’t inspect the nozzle closely before the flight, but I certainly didn’t notice anything odd as I was installing the initiator and the little bit of orange heat shrink to retain it.
After the flight it looked like this:
Date code on the motor (it’s from a bulk bag of 25!) is 030121-01.
I have filed a MESS report and also written Karl already.
(I had two Estes CATOs today as well, an A10-0T and a D12-5 — the latter blew up my Green Eggs. So three motor anomalies in 11 flights and 12 motors. Not a good average and much worse than I normally see.)
I have well over 100 Q-Jets on hand (mostly 18mm Cs and Ds). None have been made more recently than August of 2021. And, until today, they’ve generally worked pretty well and have been trustworthy and consistent. But now….I have to wonder what will happen next time, at least with White Lightning motors. *sigh*