Whats up with Aerotech Delays?

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Well-Known Member
Apr 1, 2004
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I launched several AT reloads this weekend and here's what I got.

E18-4... launched 2 both delays were over 6 seconds.

E23-5... more like 3.5 or 4

F22-5... This one was way early. 3 seconds at the most . This one tangled the chute. Luckily the chute did open at about 200'.

Was this just a bad delay day or has anyone else had these kind of problems?
I have witnessed an H123M act more like a short.
I have also seen a G64-7 finally eject at about 11 seconds.

They must be having some quality problems.
I have seldom gotten short delays, more often "bonus delays". Part of the problem is the design of composite motors - since the delay burns at different rates under pressure you must get a clean ignition at the head of the grain or the delay will be off - there is a good explaination in the latest Exteme Rocketry. But I also think the other part of the problem is quality control at AT.

Dale Greene
At the last launch:
Saw an AT "G" with around a 1 to 1.5 second delay. It was not mine.

My daughter's AT Initiator on an E11-3J had around a 5 or 6 second delay - in fact deployment occured about 0.00001 seconds after it had a wonderful lawn dart.
It now flies with several wraps of duct tape.

Yes - I've seen some problems.
See...this is what scares me about AT motors!

My Commado Cody Rocket flew beutifully on an D21-4 but unfortunately it turned into a D21-8 and deployed the chute 4' from the ground...at terminal velocity.

Slowed the model down enough for a safe landing but the chute was trashed.
A couple of months ago I launched my venerable (35th flight) North Coast "Big Brute" on a G80-4 that turned out to be a 1.5 or 2 second delay. Deployed the nosecone but snapped the 12' shock cord in two. The nosecone came in ballistic ( had 4oz. of nose weight) and shattered on impact. The airframe floated off the field to the East and hung up in a 20' tree.

Now I'm wondering what to do with the other 3 G80's that I bought at the same time.

I think the G80's had a bad batch , IIRC AT where asking customers to return any G80 ejection caps (POP*) in a certain batch number.

*= Proof of Purchase.

Are you thinking of the G35s? Speaking of which, i have not been asked for an ejection cap yet...
Well I knew it was some type of AT G motor :rolleyes: Well we had someone in the UK asked to send his pack of motors back to AT but they sorted something out ( Shipping prices too high ) , and AT asked for the ejection caps to prove that he has actually got the motors. But they said they will send some new motors out to replace them but Im not sure if he has recieved them yet.
I had an Initiator with an E16-4 at LDRS in Argonia. The Ejection charge went off imediatly after it lawn darted into the crowd :eek:

Flew an H128-6 that was about an H128-9 Saturday.

Had a spool with a F40-4 that was more like a 7. Oh yea, it was a 4-H competition flight. Parachute poped out while it was bouncing.

Probably many, many more
Argonia, Initiator, E16-4, ejection right after impact, exactly what happened to me.Maybe I'll have better luck this time.
Originally posted by Blue_Ninja_150
Argonia, Initiator, E16-4, ejection right after impact, exactly what happened to me.Maybe I'll have better luck this time.

Was it at LDRS, or when? That is weird
I'm telling you...there are just way too many of these "bonus" delays!
Kloudburst. More like a 8 second delay than a 4. Might have had to do with me storing it in a ziploc. first reload, learned my lesson.
The only ones I have consistent problems with are the E16-4's. I think it's because the propellant is soooo far away from the delay grain that it doesn't start burning as early as it should...

Yeah, but the E23 grain is also that far away and I still got 3 seconds from it not 5. The E23 is a quicker burn and is a blue motor, but I don't think thats the problem.