D12-0 blow out!

[Dr.Zooch]

During the boost- yes. At ejection the lifting body does a loop and then points directly down until energy balances and then it levels out- at that point the cam looks ahead and down at a point that is just about 5 degrees ahead of the landing spot- that was the best that I could aim it. Because the window is bent the lower portion is distorted so the cam has to look a bit up.

 

[pkmpd]

We have also had 2 D engine malfunctions recently, the last one today with a D12-3 ejection charge malfunction, resulting in a destroyed Maxi-Brute Honest John.

We had another D12-3 a couple of months ago, which upon ignition blew a ball of fire up through the body tube of a Maxi-Brute V-2, knocking the nose cone up into the air.

Are there other D engine failures out there? Has anyone ever contacted Estes concerning engine malfunctions? Are they receptive to this type input? Is it worth my time and effort?

BWP

I had the same kind of Estes "D" malfunction at a school rocket show. It was kind of cool to watch, the D12-5 blew the motor core out of the fore end of the rocket. It sounded like a shotgun report. Kinda looked like a Hellfire missile going downrange, a bright glowing projectile that was dancing back and forth like a knuckleball baseball pitch does. It ruined the chute and shock cord but the rest of the rocket was fine. The engine nozzle was gone and the casing was strangely smooth inside, just like it had never been loaded at the factory. I told the kid that owned the rocket to send the engine to Estes and they'd make it right. I forgot to send in a MESS. Overall, since it wasn't my rocket and it was very neat to watch...I liked it.

 

[SwingWing]

I had the same kind of Estes "D" malfunction at a school rocket show. It was kind of cool to watch, the D12-5 blew the motor core out of the fore end of the rocket. It sounded like a shotgun report. Kinda looked like a Hellfire missile going downrange, a bright glowing projectile that was dancing back and forth like a knuckleball baseball pitch does. It ruined the chute and shock cord but the rest of the rocket was fine. The engine nozzle was gone and the casing was strangely smooth inside, just like it had never been loaded at the factory. I told the kid that owned the rocket to send the engine to Estes and they'd make it right. I forgot to send in a MESS. Overall, since it wasn't my rocket and it was very neat to watch...I liked it.

Sounds like the classic "ejected burning propellant slug" There is even a check box for it on the NAR MESS form.

 

[DaveCombs]

Doc: How's the view out of the canopy? Do you get much distortion from the curvature or the plastic?

 

[Dr.Zooch]

I just started a new thread on the lifting bodies- your answer will be there.