AT K375NW, I59NW, and other end burning motors in longer cases with RAS

[Mike Thomas]

I have a question I’m hoping someone can help with an authoritative answer. I have a 54/2800 case and the RAS. For the K375WN-P motor, can I use the RAS with one spacer and the floating forward closure in the 54/2800 case, like with other 2560 motors in a 2800 case? I see the Aerotech Motor instructions call for a plugged forward closure for end burning motors in the 2560 case, but all of the case specific instructions don’t accommodate the use of the RAS specifically. Can I simply plug my floating forward closure with grease, like I do for other motors that I don’t use motor ejection, or do I have to buy a different case and/or closure? I see there is a floating plugged closure. Do I need that forward closure for this motor with the RAS spacer or can these end burning motors only be used in their designated case size with a plugged forward closure?

Same question for the I59NW. I have the 38/720 and RAS.

 

[sl98]

This thread doesn't specifically address the RAS but I think probably not. I would heed the last post of the thread.

https://www.rocketryforum.com/threads/aerotech-i59-forward-closure.133194/

 

[Cameron Anderson]

I have a question I’m hoping someone can help with an authoritative answer. I have a 54/2800 case and the RAS. For the K375WN-P motor, can I use the RAS with one spacer and the floating forward closure in the 54/2800 case, like with other 2560 motors in a 2800 case? I see the Aerotech Motor instructions call for a plugged forward closure for end burning motors in the 2560 case, but all of the case specific instructions don’t accommodate the use of the RAS specifically. Can I simply plug my floating forward closure with grease, like I do for other motors that I don’t use motor ejection, or do I have to buy a different case and/or closure? I see there is a floating plugged closure. Do I need that forward closure for this motor with the RAS spacer or can these end burning motors only be used in their designated case size with a plugged forward closure?

Same question for the I59NW. I have the 38/720 and RAS.

K375 isn't an end burner. It's dual thrust. I've flown mine with a plugged threaded RAS closure twice. Long burns don't do well using just grease to plug a standard closure - I would avoid doing that.

 

[Neutronium95]

I have a question I’m hoping someone can help with an authoritative answer. I have a 54/2800 case and the RAS. For the K375WN-P motor, can I use the RAS with one spacer and the floating forward closure in the 54/2800 case, like with other 2560 motors in a 2800 case? I see the Aerotech Motor instructions call for a plugged forward closure for end burning motors in the 2560 case, but all of the case specific instructions don’t accommodate the use of the RAS specifically. Can I simply plug my floating forward closure with grease, like I do for other motors that I don’t use motor ejection, or do I have to buy a different case and/or closure? I see there is a floating plugged closure. Do I need that forward closure for this motor with the RAS spacer or can these end burning motors only be used in their designated case size with a plugged forward closure?

Same question for the I59NW. I have the 38/720 and RAS.

The K375 is a normal motor, with no endburning grains. It'll work fine with the RAS. The only endburning 54mm motor is the J99, and Aerotech sells a plug that goes into the delay well to seal it, instead of making an entire forward closure just for one reload.

As far as I know, the only certified configuration for the 38mm endburning motors is with the endburn forward closure. That said, if you filled the delay grain well with a solid plug, like Aerotech uses on the J99, and it sealed properly, I don't see why the RAS couldn't work. Your best bet might be a delay grain, and the associated insulator and o-ring. Probably best to inhibit the face of it just to be safe. That would be an uncertified configuration. @AeroTech would have a definitive answer for you.

 

[AeroTech]

Only use the plugged endburning closure or plug with the appropriate length case for the endburning reloads.

 

[Mike Thomas]

Only use the plugged endburning closure or plug with the appropriate length case for the endburning reloads.

Thanks @AeroTech! Can you confirm if the K375 falls into this category or if it’s not truly an end-burning motor? Thanks!

 

[Neutronium95]

Thanks @AeroTech! Can you confirm if the K375 falls into this category or if it’s not truly an end-burning motor? Thanks!

Here's the cutaway drawing, so you can see for yourself.

https://d3l66gvjdr7rqw.cloudfront.n...mages/54-2560_k375nw-p_assy_1648847969298.pdf

 

[Mike Thomas]

Here's the cutaway drawing, so you can see for yourself.

https://d3l66gvjdr7rqw.cloudfront.n...mages/54-2560_k375nw-p_assy_1648847969298.pdf

Excellent! Thank you, @Neutronium95! That definitely clears it up! Where can one find the list of all technical drawings to link to the documents? I haven’t been able to find them on the AT website!

 

[3stoogesrocketry]

Excellent! Thank you, @Neutronium95! That definitely clears it up! Where can one find the list of all technical drawings to link to the documents? I haven’t been able to find them on the AT website!

RCS Rocketry site is my go to

 

[bad_idea]

Excellent! Thank you, @Neutronium95! That definitely clears it up! Where can one find the list of all technical drawings to link to the documents? I haven’t been able to find them on the AT website!

Aerotech Recources page at RCS.

 

[Mike Thomas]

Thanks for pointing me to the resource page for these drawings. Was also able to confirm the K375N uses the standard or plugged forward closure. Thanks folks! Bought a couple of them! Hoping to enjoy the dual thrust this weekend!