I finally had one!

[DynaSoar]

CATO.

On its first flight (E9-4) my Estes Falcon did fine, except the fact it arced over to 45 degrees after about 100 feet and must have looked to the nearby R/C aircraft guys like I was hunting them down. Actually, an impressive looking flight. Still, ejection and recovery were fine.

On its second flight (still E9-4, identical in every way) it arced over 80 degrees immediately off the rod, took off nearly horizontal away from me, veered 30 degrees left, rolled and veered right 90 degrees, and dove at about 20 degrees down, plowing into the soft hayfield ground under power. I heard it still firing, then the smoke, then the ejection. Only smoke rose from the hayfield; I could see nothing.

When I got there, it's rather large nose was buried completely up to the body tube in the mud. From the fins on back, not a scrtach. But the upper body had blown and shredded for 6 inches back from the top, and around half its circumference. I'm glad now I didn't spend the time to put all those decals on.

These E9s were from the same batch I got that had several with poorly made nozzles (crumbled easily under even slight pliers pressure trying to remove them). I'd suspect the nozzles shredding, but several other birds using similar engines didn't do this. OTOH, those other birds were far more stable and it may have been less apparent; many of them did arc more than I'd expect them to.

I think I'll call Estes and see if I can find out about these nozzles.

 

[Karl]

I've had nozzles like that aswell. More times then none , my motors nozzles are smooth , grey , with a smooth texture. But sometimes they are more like white , look and feel like sand . But I've never had a problem with them

 

[DynaSoar]

Originally posted by Karl
I've had nozzles like that aswell. More times then none , my motors nozzles are smooth , grey , with a smooth texture. But sometimes they are more like white , look and feel like sand . But I've never had a problem with them

I actually have some made on the same day, three E9-4's with smooth white clay, three with what seems to be large grains of different colors of grey, and three E9-6's with this same grainy look. I've burned plenty of both, and they both had similar problems. As to what that problem is, see under "Propulsion".