CTI 38 and 54mm CATOs

[Andrew_ASC]

I flew one Aerotech DMS and disliked how it was non inspectable. My H219T-14A didn’t Cato either. The CTI instructional videos show a guy carelessly under time dropping the black inner motor assembly into a 1G motor.

 

[Andrew_ASC]

I often pull the grains out and inspect my CTI motors. I think the nozzle is the only thing glued to the liner and not removable.

You are doing the right thing. Meanwhile CTI teaches people how to not inspect a motor.

 

[crossfire]

I flew a CTI 54mm J250 Skid today and it was a great flight. I am happy

 

[Steve Shannon]

You are doing the right thing. Meanwhile CTI teaches people how to not inspect a motor.

That was always the thing with CTI motors, that they were fast easy to build. They had already done the inspection and assembly of everything except the case, thus avoiding the common mistakes people might make with Aerotech that might lead to problems. That, plus the ability to adjust the delay manually rather than selecting short, medium, or long delays meant greater flexibility yet less hassle. For years most people had very few problems with CTI. As their motors became more popular there were inevitable problems. I still don’t think they have a statistically large number of problems in general, but the 38 mm forward closure material problem that led to the recall hurt them badly and left people sensitized.
I won’t hesitate to fly CTI motors and I probably will never disassemble the reload and inspect it. Unless you know what you’re doing that just introduces the possibility of user errors.

 

[Andrew_ASC]

Hmm. I never thought of it that way.

 

[djs]

FWIW- I flew a 54-5 grain motor this weekend. The night before, I epoxied the forward closure in with 5 min epoxy. Motor flew great. Also flew a 3 year old I470WT (38mm). No issues there.

However, two of the motors I flew this weekend (the aforementioned 54, and the upper stage of my 2 stager- 1 grain 38) were both CTI blue motors, and neither lit with the given ignitor. I was able to start the 54-5 with one of Wildman's ignitors. I'm wondering if there's an issue with getting these to light, or maybe it's just operator error. Normally blue motors are some of the easiest to light, so I dunno what's going on there.

 

[mikec]

I'm wondering if there's an issue with getting these to light...

I've never had any issues with the blue. You have to have the igniter all the way up next to the BP pellet, though; if it slips down then it can fail to start the motor.

 

[grouch]

I’ll keep flying CTI’s 29mm stuff until the cows come home...and I live in an apartment. I think they offer a great product with excellent flight choices. While I actually like assembling AT motors more, CTI’s have options AT doesn’t. They are my “in field quick turn around” motor. Sad to see the issues with the larger loads.

 

[boatgeek]

I don't think the inspection issue is a big deal. You pretty much have to take the forward closure off to adjust the delay, so you can look at the top of the first grain no problem. If you feel like dropping out the rest of the grains, you can go ahead and do that in a couple of seconds.

 

[JimJarvis50]

FWIW- I flew a 54-5 grain motor this weekend. The night before, I epoxied the forward closure in with 5 min epoxy. Motor flew great. Also flew a 3 year old I470WT (38mm). No issues there.

However, two of the motors I flew this weekend (the aforementioned 54, and the upper stage of my 2 stager- 1 grain 38) were both CTI blue motors, and neither lit with the given ignitor. I was able to start the 54-5 with one of Wildman's ignitors. I'm wondering if there's an issue with getting these to light, or maybe it's just operator error. Normally blue motors are some of the easiest to light, so I dunno what's going on there.

According to CTI, their blue formula is actually the most difficult to start (unlike other blue formulations). That said, if your (ematch?) igniter didn't light the pellet, then that was the problem.

Jim

 

[djs]

According to CTI, their blue formula is actually the most difficult to start (unlike other blue formulations).

Interesting- I wonder what's different about their blue from others.

Any suggestions on CTI propellants that light faster?

 

[JimJarvis50]

Interesting- I wonder what's different about their blue from others.

Any suggestions on CTI propellants that light faster?

I have a list somewhere. I recall that white and white thunder were on the faster end of things. I was interested because I want to light a motor at 50K. The answer to that, though, has more to do with how you light the motor than what the formula is.

Jim

 

[crossfire]

I have a list somewhere. I recall that white and white thunder were on the faster end of things. I was interested because I want to light a motor at 50K. The answer to that, though, has more to do with how you light the motor than what the formula is.

Jim

The V-Max is very fast to light.

 

[Clivus]

Here’s my L935 failure from Airfest. I’m not sure what happened, but I feel like it was my fault. I am afraid I didn’t have the motor all the way sealed in the case. I tried to find the cardboard tube to get the date code, but I had thrown it out and the trash was taken the next day.