CTI H163 question

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

qquake2k

Captain Low-N-Slow
Joined
Jan 26, 2010
Messages
13,574
Reaction score
65
Has anybody ever seem this? I last flew my Binary Effusion on a pair of CTI H163 White Thunders. I just pulled the cases out, and noticed that one motor is much shorter than the other. It looks like it shrunk. I've never seen that before.

H163_01.jpg

H163_03.jpg

P1100217.JPG
 
Were they the same length when assembled? Only trying to eliminate a mislabeling issue.
 
Yes. Happens quite often to CTI loads. As they burn, the liner melts and shrinks. Sometimes it happens more than others. Just depends on the motor itself and how it burns. No big deal.
Nice pic, by the way!
 
Jeron from CTI told me most of the melting and shrinking of the liner happens after motor burn out. Case is heated up as motor burns. As long as the case has no damage the liner did its job.
 
Like Erik said. This is 100% normal. The liners get soft and start to melt. When the motor shuts down, there is a vacuum effect on the case and the pressure change pulls the front of the liner down towards the aft.

I used to think this was from the ejection charge pushing on the liner. The differential pressure thing was told to me by Dr. J.

No worries, throw them away and burn another one.

And Mark, no way would the motor even have worked if it were the wrong motor for the case.
 
So to quote George Costanza, "Yes. Significant shrinkage!"
 
Jason. I once flew a two grain motor in a three casa and forgot to put in a spacer it worked pefect. I got lucky
 
Thanks for the replies, guys. Never happened to me before, I thought it was odd.
 
Jeron from CTI told me most of the melting and shrinking of the liner happens after motor burn out. Case is heated up as motor burns. As long as the case has no damage the liner did its job.

How is Jeron doing? Didn't he get burned in the CTI fire?
 
Back
Top