Question on the Aerotech RMS 29/40-120

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Well-Known Member
Dec 4, 2003
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I own the book "Modern High-Power Rocketry" by Mark Canepa, and have read the parts relevant to motor reloading, notably the section on reloading a Dr. Rocket 29/240 case. It looks simple and straightforward.

However, I currently own an Aerotech RMS 29/40-120 casing, which came with my initiator starter set back in February. The casing is somewhat "different" than the Dr. Rocket ones, but appears fundamentally the same.

Question(s): Do I load a 120mm load into the Aerotech phenalic motor in exactly the same way I would a re-load into the Dr. Rocket motor as illustrated in Mark Canepas book? If not, what aspects are different?

I have an E23 reload on its way from RAH I would like to use, you see :D

PS: I also just placed a bid on ROL's auction boards for a Dr. Rocket 180 complete motor, although I wont have anything to fly it in until I buy the PML Phobos later this year for Rockstock XX. $39...good price for a complete and unused RMS 29/180 ;)
Well, until you get the reload you may want to watch the instructional video on AeroTech's site to familiarize yourself. Also, the reason that a 29/240 load is loaded differently is that it is a high power load, not hobby load like the 29/40-120. Whether it is made by Dr. Rocket or Aerotech is irrelevant, because they are essentially the same. However only AT makes the hobby casings so that may be kind of confusing. Clear instructions are provided with that specific load once you get it so all you have to do is follow them, no guesswork. Although, I'm not exactly sure what you mean by "120mm" and "phenolic motor".
Yeah, the concept is the same but the particulars may differ between loads. Just be sure not to overdo it on O-ring grease. Get 'em shiny and that's all. Also be careful not get grease on the delay element.

I built my first reload completely on my the instructions, watched the AT videos, then read the instructions again during assembly. Worked fine. But I would always advise flying some single-use motors first beforehand.
Already flown 'em with 24mm SU motors using a motor adaptor first...and of course I flown dozens of smaller BP motor rockets as well, work my way up the ranks agonizingly slowly.

Once I run out of F21 SUs' it will be way passed time for me to move up to the next step :)

I was un-aware of the motor-reload videos over at Aerotech's website though...I haven't visited there much. Once I knew to look for such a video I found it imediately however :D. Thanks for the tip.