75 mm crossloads

[jfcote]

I am looking at acquiring 75 mm hardware soon. My initial plan was to acquire a 4 grain 75mm CTI case. With the supply issues, getting CTI motors is not easy right now. I saw that most AT 75mm motors are certified to be used in CTI hardware (crossloads). Just add the forward seal disk and you are good to go. Is there any issues to use 75mm CTI hardware with 75mm AT reloads? I am looking at people real life experience.

 

[ECayemberg]

No problem whatsoever...some actually prefer the CTI 75 and 98 hardware to the AT hardware. I've flown AT 75mm loads in CTI hardware for years; only recently have I owned Aerotech 75mm hardware. Green light!

 

[jd2cylman]

I’ve flown several different CTI loads in AT 75mm hardware without issues. I’ve used two, three, and four grain loads. I always use the AT seal disc, even if I have to leave out grain spacer orings to get enough room for the seal disc to seat fully. All loads have performed nominally.
I’ve also flown one 98/5120 (M1650) load in a AT case without issue.

 

[jimzcatz]

And to top it off, CTI gives you O-rings in their loads to use in Aerotech hardware!!

 

[ep29030]

I’ve flown four CTI 75mm 3 grain and one 75mm 2 grain loads in my AT hardware without issue.

 

[Hobie1dog]

Great information, thanks everyone.

 

[cerving]

I've done a lot of AT crossloads, I have CTI 75/3G and 75/5G cases. Pretty sure virtually all of the AT 75's call for the FSD, and I usually put both the AT-provided o-rings and the extra CTI nozzle/FC o-rings in. Never had any problems with them.

 

[jfcote]

Just to confirm, if you purchase a 75mm AT reload and you intend to fly it in 75mm CTI hardware. Are all the necessary o-rings provided with the AT reload to be used in the CTI case?

 

[ATGM]

Just to confirm, if you purchase a 75mm AT reload and you intend to fly it in 75mm CTI hardware. Are all the necessary o-rings provided with the AT reload to be used in the CTI case?

Yes that is correct.

 

[Cooperr]

I’ve flown several different CTI loads in AT 75mm hardware without issues. I’ve used two, three, and four grain loads. I always use the AT seal disc, even if I have to leave out grain spacer orings to get enough room for the seal disc to seat fully. All loads have performed nominally.
I’ve also flown one 98/5120 (M1650) load in a AT case without issue.

I'm considering loading a CTI M1560 into an AT 98/5120 case for a future L3 cert, do you know if this specific motor/hardware combination is certified?

 

[jsdemar]

I'm considering loading a CTI M1560 into an AT 98/5120 case for a future L3 cert, do you know if this specific motor/hardware combination is certified?

Yes, it should come with both sets of o-rings (CTI and AT).

https://www.nar.org/wp-content/uploads/2014/08/CasingCrossCert.pdf

 

[Cooperr]

Yes, it should come with both sets of o-rings (CTI and AT).

https://www.nar.org/wp-content/uploads/2014/08/CasingCrossCert.pdf

Got it thank you. Does this document mean I'm for sure fine to do it for a cert flight?

 

[jsdemar]

Got it thank you. Does this document mean I'm for sure fine to do it for a cert flight?

I think so. Double check with your TAP or L3CC people.

 

[jd2cylman]

I'm considering loading a CTI M1560 into an AT 98/5120 case for a future L3 cert, do you know if this specific motor/hardware combination is certified?

I’ve flown the exact configuration a few years ago. Worked great. It was going to be my L3 motor, but I acquired a M1939 before the day arrived and went with it instead.
Used it the next launch with no problems.