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It was a copy and paste from Paul. Typos happen. From the post:

K850DM-16A

This motor is a 54 MM-2560 case reload in the Dark Matter propellant. Specifics are as follows:

Total Impulse 1869.13 NS
Max Thrust 1094.56 N
Average 922.6 N
BurnTime 2.028 Seconds
TMT Metric K922 (45% K)
Total Weight 2041 G
Propellant Weight 1224 G


K990DM-14A

This motor is a 54 MM, 24” long Single Use motor, also in the Dark Matter propellant. Specifics are as follows:

Total Impulse 1867.13 NS
Max Thrust 1075.85 N
Average 931.9 N
BurnTime 2.04 Seconds
TMT Metric K931 (45% K)
Total Weight 2109 G
Propellant Weight 1224 G

Per above, the K850 is a reload for the 2560 case while the K990 is a single use DMS motor likely using the same case as the L1000W DMS. A difference of 2 NS between the two, or .012 s in burn time, or 9.3 N of average thrus - virtually identical. The difference in classification (K850 versus K990) would be product differentiation I would imagine (L1000W DMS versus L1090 RMS, among others, although they didn't do that for the H550ST DMS/RMS for some reason).

Regarding which one is the actual DMS/RMS version? I'll defer to whatever Charlie said :).

I understand typos happen, but should this many happen in 1 post from the certification group? That's what bothers me most. What other typos do we have?
 
In this case, I have the test stand data from the cert tests, and that is correct. I have emails back and forth with Charlie and Gary too. I can say my files are good.

Typos do happen. It appears the error occurred going into the cert document.
 
I believe I flew the first ever certified K2050 in my Nike Smoke yesterday at TCC October Skies -
3zF0urS.png


It was spectacular. More later.
 
I can't be the only one whose fingers are itching for an updated price list...
 
will have to try the Super Thunder next if its not a plugged motor.

It is, sorry.

Various pictures and notes online will say that it ships with a 14 second delay but it needed to be plugged for certification at the last minute.
 
Can some one remind me how to plug a motor using grease? Is this considered modifying the motor?
 
Can some one remind me how to plug a motor using grease? Is this considered modifying the motor?

I use a plugged forward closure for my plugged reloads. You just install the delay grain as usual. If you are using an open forward closure, you assemble the delay as you would normally but put grease on the end of the delay grain facing the charge well, and leave the well empty of course. I think some folks fill the ejection well with grease, but I don't.

Using a plugged reload in a motore case with a plugged fwd closure is not considered modification. Not sure about using a plugged motor reload with an standard open closure.
 
I use a plugged forward closure for my plugged reloads. You just install the delay grain as usual. If you are using an open forward closure, you assemble the delay as you would normally but put grease on the end of the delay grain facing the charge well, and leave the well empty of course. I think some folks fill the ejection well with grease, but I don't.

Using a plugged reload in a motore case with a plugged fwd closure is not considered modification. Not sure about using a plugged motor reload with an standard open closure.

Unless absolutely necessary to plug the closure, just assemble the motor as instructed and fill the ejection charge cavity with packed dog barf (instead of BP) and cap/tape over. Then you get to keep the delay element which is also the tracking smoke generator. The delay will not burn through until after the propellant has burned and pressure dropped inside the motor. The only thing that can really go wrong is if the delay element has some kind of failure that results in a Cato (like burning up the outside of the delay because of a loose fitting delay grain or delay grain insulator would be one example).
 
Was gonna fly a K1000 at MWP (picking up the motor from Tim). Considering the overnight cure requirement, I may bring an alternate motor. The L1000.
 
Speaking of the L1000- are the thrust rings ok on these now? Thinking of picking one of these up at some point.
 
Speaking of the L1000- are the thrust rings ok on these now? Thinking of picking one of these up at some point.

They ship them with the thrust rings off, you have to glue them on now. Even if they're on, it doesn't hurt to add a little CA as a backup. More troubling to me is the forward closures... I had two flights at LDRS with them, and both of them blew out the forward closures. The first one blew right away, reaching an apogee of about 1,000' instead of 11,000', and was forceful enough that it blew the guts out the back and took the Aeropack screw-on cap with it. The rocket had a solid builkhead in front of the motor mount, so fortunately it did no damage to the rocket. Since AT was on-site, we gathered up the pieces and brought them to their table, they gave me a replacement.

The replacement went all the way to 11,600', and I was quite satisfied... until I got home and took out the motor. Seems the forward closure had actually let go, but apparently it was late enough that it didn't have a significant effect on the flight. I'm done with the L1000 DMS... at least until I see an actual advisory from AT that they've fixed the forward closure issues, which seems to be why they're failing now.
 
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