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Discussion in 'Propulsion' started by ATGM, May 16, 2015.
most likely not surfing.....
The 38mm end burning forward closures were not on order for whatever reason. I am correcting that now.
Would like to get the warranty hardware before its one year anniversary.
I have been looking at many vendors to find the 54mm adaptor system out of stock. Any idea on the current lead time?
We now have all the parts in stock and we should begin shipping them to the dealers early next week.
Note that the 54mm system will now include two standard case spacers and one short spacer for use with the 54/2800 case.
Completely understandable and we apologize for the delay.
I'm just getting back into this (2nd childhood, heading for retirement in 2 years max, Lord willing!), and like the idea of "D" motor impulse in an 18 mm (basically A, B, C) engine size, so when I saw your RMS 18/20 system, I was quite happy. But on the other hand, I am just getting back at this, and don't know if I'll be out flying every Friday night at 5:00! So, with the vagarites of business, if I sunk $80 or $120 into 3 cases, well... are these real popular? I have hopes of clustering 3 some day and would like to have a few loaded ahead of time for my first few single engine flights. But I'd hate to lay that kind of money out only to find out I'm one of 6 or so in the country that like them, and they up and get discontinued...
I'm building a couple of larger rockets that only project 200-300 ft. on C motors, I think the D's would be very nice.
Thanks, don't mean to be impertinent.
i have an 18/20 case, got it back in the 90's when it came out. no doubt it has its place in the line up, and i sure do prefer the 18mm white lightning loads to the q-jet black loads.
we have them in stock ready to ship
Question for Aerotech. Why are there no Mojave Green 38mm DMS motors? 29mm has a few single-use/DMS greens but no 38’s.
We don't have a DOT approval for single use high-power greens as I recall. We could however package the grains as a reload and the customer could assemble it...
Not sure you can share it, but is there a specific reason why you don't have DOT approval for greens? Or just "not worth the time at this point?"
Much thanks! Personally I think have full "D" impulse in an 18 mm case is great. I want to put it in a couple of demonstrators (Estes's Mercury Redstone & Venus Probe) where think they will perform well.
D21s are available at RocketryWorks. No D10s (shown as discontinued by manufacturer).
Not really worth the time and cost. $10,000+ these days to test and classify “new explosives”, plus months of waiting. And you’re locked into whatever configurations were specified in the approval request. There is a chance that the approved testing lab could issue a recommendation “by analogy” to the reloads but that would still likely cost several thousand $$.
Hi Tom, we discontinued the D10W and D21T because our 18mm case vendor sent us a bad batch of the casings and we lost confidence that they would be able to produce reliable molded cases moving forward. It is possible in the future we could approach the vendor that makes our 24 & 29mm casings, but that would involve a relatively large mold expenditure that isn’t currently in our budget.
To me the loss of the D21 is heartbreaking... I loved these motors, especially the D21's... but thanks for giving the reason. It makes sense since I'd rather not have detonations in the field... Unfortunately I can't see springing for the 18 mm case at the moment. While the short delay D24 would work just as well as the D21 in my Estes Phoenix, I would prefer to use a single use motor in anything that flies over 500 feet... The New England launch scene isn't conducive to recovering high flying narrow diameter rockets. (As in, I can't cram my chute release into them and there are just too dang many trees around here).
You can always use it for the heavies like the Saturn V
Only for the sake of technical accuracy, no APCP motor ever “detonates”. The case bursts because the pressure within exceeds the case’s ability to withstand such pressure.
A true detonation would release much more energy and consume nearly all of the propellant.
It’s important because a significant portion of our lawsuit was correcting misunderstandings about how rocket motors work.
Yeah I know... but I just like saying "detonate".
Did you look into G12 glass/epoxy? I've got a quote in with Franklin Fibre for 500 and 1000 feet. I'll let you know what they say. Even if it adds a $ or so to the cost, it would be worth it and you could also bring back the longer 18mm such as the E45 and F55 Make them with no thrust ring like the 1990 style. Tape still works
There's barely enough market for the D21/D10 motors at their current price. Using fiberglass casing would raise the SRP to $20-30 each.
There's even less market for the E45/F55 motors. I wish it was not so as I had fun helping develop those motors.
54mm Reload adapter system question. Will there ever be a thredded floating style closure that will work with the adapter system? One of my projects makes use of the threaded forward closure as a shock cord attachment point and I can't use the adapter system because the tapped floating forward closure does not exist.
No need for the heartbreak - they were kinda expensive ($8/per), and have been superseded by Quest motors: C12 and D16 are $4.50/per, and a WHOLE lot of fun to burn.
If that's not enough, there are the 18/20 re-loadable D13 and D24 motors ($5.50/per)
Wipe away your tears, and open up the wallet !
18/20 case is < $35 these days.
That's about the cost of 4 old D21s, and I know I burn more than 4 motors when I bring my 18mm supplies out for a launch day!
With Q-Jets widely available at 1/2 the price of the old D21/D10, I would not look twice at the oldies.
Progress is great.
Thanks Aerotech !
I'm a big fan of the Q-jets D16 and always found the price of the D21/D10 to be too high for my taste.
The Q-Jets don't replace them. The D21 and D10 had significantly higher total impulse and initial thrust, and really could do things the Q-Jets can't.
You mean this, or something else?
In fact, at least by the 10/29/2018 price guide I had handy, the RAS closures are the only forward closures listed, so non-RAS forward closures seem to be a thing of the past for 54mm.
+1, the d21 is a sad loss for me, topload into a tailcone and high-transonic at low altitude. Seems tragic now that we have 18mm glass and small enough electronics.
I had rather hoped the sales trend would move the other way and open up possibilities for the long 18's. Ah well, c'est la vie.
I got my entire stocks of D10s and D21s from valuerockets.com before Aerotech shut that part of the business down. I have a handful of each left. I’ve not bought any since the effective significant price increase of closing down valuerockets.com.
I agree the Q-Jet D16 is not a direct substitute. It’s barely 13 N-s vs. the full Ds of the D10 and D21. The D16 IS fun though.
I do have one 18/20 case so I expect I’ll eventually use it where I want a full D in 18mm. But SU motors have that “well if I lose it, it’s not a big deal” factor, which led me to put a D10 in a BMS School Rocket once....and I did get it back.
For me the real star of the Q-Jets is the C12. I’m about to get into my second 25-motor bulk pack of C12-6s.
That is a possibility but like Bob said there is very little market for these motors. The nozzle becomes a separate expense and the case must be prepped and the nozzle bonded in. It would be more of a “fun” project than a business decision.
can anyone tell me if there is a source for info on which size nozzle a specific Aerotech reload uses? I am mainly looking for info on 29MM and 38MM reloads. Thanks for any help.
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