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muddymooose

Hoopy Frood
Joined
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Location
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This has to be a mistake, right? Shouldn't this be 5-7 seconds?

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I'm eyeing that CTI I150 also. It meets min specs. Depending on launch rail length it might or might not be safe enough if a tard flies it off a four foot rail. The CTI I100 may require plugged forward closure and electronic deploy like an Aerotech I1299N that had 0.3s burn. Idk. I don't fly much Cti.
 
What rail lengths are these rail exit velocities spec at?
 
It seems reasonable that the I100 motor delay would be in the same range as the other motors suggested, possibly there is a error, might be a good idea to send a contact report to TC (or John Coker iirc, hes one of the guys behind TC).
 
Okay I stand corrected...the other motors only burn for ~1-3s, so with a 5-7s delay they're at ~6-10s total time.

The I100 burns for 6.2s, so with a 1s delay it's at 7.2s. Still it seems weird for ejection to start only 1s after burnout. You can't even drill down an I100 to 1s...7s is minimum.

Regardless I may have to rethink the load I'm using for my Warlock shakedown. The other I loads look better.
 
Delay is based from burnout, however on composite motors the delay is in most cases lit at motor ignition, but it is still timed from burnout. According to the TC stats and the actual burn time, the flight is 10.4 seconds to apogee, the motor burns for 6.2 seconds therefore the delay should be 4.2 seconds long, not 1 second long (of course I may be wrong too!). I went back and checked my math on the I445 and J1055 and it works out both of them burn for 1.1 and .7 seconds each and the delays work out to about what the TC shows then to be 6s and 7s.
 
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Okay I just had a teachable moment. Delay is measured from burnout and not from ignition as some posts would have had me believe.

Regardless, since it is impossible to drill down an I100 delay to 1s using commercially-available tools (yeah you could dig it out with a screwdriver or awl or whatever) it probably shouldn't be listed as a viable motor for this rocket.
 
Okay I just had a teachable moment. Delay is measured from burnout and not from ignition as some posts would have had me believe.

Regardless, since it is impossible to drill down an I100 delay to 1s using commercially-available tools (yeah you could dig it out with a screwdriver or awl or whatever) it probably shouldn't be listed as a viable motor for this rocket.

Actually attempting to shorten the delay under 3-4 seconds iirc can cause the delay to fail allowing the still burning motor to vent forward into the rocket precipitating a forward closure failure, shortening the delay to much affects its structural integrity.
 
Actually attempting to shorten the delay under 3-4 seconds iirc can cause the delay to fail allowing the still burning motor to vent forward into the rocket precipitating a forward closure failure, shortening the delay to much affects its structural integrity.

Understood. I'll go with the I218.
 
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