estes ejection charge power?

[jerryb]

at our last club launch, one member brought out a vintage X-wing fighter... C6-5 i think.... flew beautifuly... when the ejection charge blew.... BOOOM! sounded like a shotgun.... popped the shock cord in two... didnt burn it through... SNAPPED it...

has anyone noticed a trend lately for more violent ejection charges in estes motors?

just wondering... the model was moderately damaged when it struck the pavement... was kind of a sad ending to a great day of flying...

doesnt Estes put some kinda code on the engines to tell if they came from the same lot or not?

just wondering?

Jerryb

 

[jflis]

Estes motor ejection charges went up in power considerably about 6-10 years ago. For many it's a real problem. I beleive that they did this as some of their larger models were experiencing ejection *failure* due to too *small* an ejection charge (the maxi brute series for example and the Mean Machine).

It's frustrating for many models as what you describe is a common failure mode now.

 

[JStarStar]

I have definitely noticed the ejection charges have much more kick than they did back in my early rocketry days.

You used to hear ejection charges go off with a light "pop" or "puff,", now it's more like a "kaboom!"

Yet another reason to ditch the standard Estes 6" shock cords, and put in 2-3 -footers.

 

[Karl]

Somone at a club launch a few months back actually had his BT 'blow up'. Just above the MMT was a 6" hole in the BT . And the ejection burnt through the Kevlar. He fixed the rocket and went to fly it again , this time it burnt through the steel wire acting in place of the previous Kevlar.
I've only had one problem , on my Quest Spinfin. I used 4 peices of Quest wadding & the ejection still seriously burnt the bottom of the shoulder on the NC....

Karl

 

[Donaldsrockets]

I've seen Estes motors with ejection charges of all strengths. I've seen one or two where the ejection charge did *NOT* fire at all, resulting in prangs, to ones that were barely enough to deploy the recovery device, hence the clay ejection cap was largely intact, to ones that were moderate, ones that were pretty strong to ones that were so powerful, they went off with a thunderous BOOM and they either ripped the cord completely out of the mount or burned it in half either way resulting in a seperation.

I've noticed though that the ejection charges on the C11's, D12's, and E9's have been pretty consistent. I think it's mostly the 18mm motors whose ejection charges fluncuate.

Too bad you can't add the ejection charge seperately to Estes motors like you can with Aerotech RMS motors so you could adjust the strength of the charge to suit your particular rocket, more for a large one, less for a smaller one.