Leads to this question..so all SU motors are hand made.....no automatic machinery used? Just thinking about Mabel.
Don't forget to put in a MESS report for the failures.
I really wasn't trying to cause a dustup over this. As I said in my post this was just a heads up for folks to check for issues prior to launch. Aerotechs response has been great. I did have one question. If I find another of these can I just drill through the epoxy? Don't really want to pay the hazmat fee to send it back.
Thank you. I have contacted Karl.
That's my one beef with AT SU engines. I almost always have to remove the labels to get the motor to fit into the MMT.Had two core samples at the last club launch. First HP ballistic recoveries that I can recall. I believe I know what caused the second one, an IO on a G77R. Yes, I have filed a MESS report and yes I have communicated with AT about it and they are replacing the motor, great warranty response. This is in the vein of a public information announcement. Normal motor function and coast. Motor recovery charge failed to fire. This was determined by post mortem exam. The bp charge chamber on the motor was not singed and the unsinged charge cap (along with the bp I assume, hard to tell on a well flown bird) were found in the bt. After I cleaned the dust from the motor charge well I observed what appeared to be epoxy in the touch hole above the delay column. I had checked to ensure that there was bp in the well, but didn't remove it. Guess that is one more thing to check with single use motors in the future. The glint in the photo is the epoxy in the touch hole. AT requested, and I sent to them the casing. The request was framed to use the casing as a training tool. I can understand that.
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I think it had to do with the MMTs. The fiberglass MMT are right on. But I built 2 kits from different vendors with paper mmts. One fit perfect and one was tight.
Hard to know at this point. The two rockets I've flown 29mm SU's in is an NCR 1/4 scale Patriot that I swapped out the stock MMT tube since it was odd sized. I can't remember where I sourced it from (over a decade ago). The other is a Sheri's Hot Rockets Mercury Redstone. I've had it for years as well, so I can't recall if I bought it from Sheri directly or from Red Arrow Hobbies after she sold out to them. Either way, I don't know where they sourced their parts, could have been anyone's. I've designed some 3D printed parts for marking fins and such; they have to be sized for the largest diameters in any given "standard" sized airframe or MMT. I learned that the hard way.
I can confirm that. My PML Bullpuppy died a tragic death, but I have the engine from the fatal flight and the label is on it.
Simple solution, get a cheap altimeter like an Eggtimer Quark. Even if you have it built for you it is the cheapen dual deploy out there. <$50 including shipping. Then you don't need no steeeenking delays... just take out the BP to use in charge wells...
Otherwise, as mentioned, chuck the delay grains and use altimeter ejection and you won't have to worry about the delay
Beh, what you said!! Needed more coffee before typing :|Err, chuck the BP, but leave the delay grain in. Or your flight will not work out
