How long can an RMS stay loaded?

The Rocketry Forum

Help Support The Rocketry Forum:

doug_kosty

Well-Known Member
Joined
Dec 20, 2009
Messages
93
Reaction score
16
How long can a Aerotech reload stay.... loaded? I have a couple of 24/40 cases loaded with D15 reloads. I carefully loaded these in anticipation of a launch 4 weeks ago - what with the bad weather (in San Diego!) the launch never happened.

I hate to disassemble these just to look at them and say "Huh" and then put the whole thing back together. So... what should I do at this point?

Let me add that these were carefully assembled with a minimum of the Aerotech supplied lube and stored at a comfortable room temperature. Should I be worried?
 

dave carver

....what hump?
Joined
Jan 18, 2009
Messages
4,973
Reaction score
5
Location
Idaho
I have a D15-4 that's been loaded for over two years and I am waiting for good weather this spring to burn it. I did the recommended procedjure(sp:p) and backed off the endcaps to ease the pressure on the O rings.

It's kind of a test of the D15-4's delay problem but only for my own satisfaction at first then the threads(yes, threads) on the motor makes it a public thing, now.

I'll let ya know what happens:snowman:
 

dixontj93060

Well-Known Member
Joined
Feb 20, 2009
Messages
13,083
Reaction score
25
My personal record is an H180 that had been loaded for over two years. Built for MWP5 at the end of Oct. 2007. But the day I wanted to launch was far too windy. I have had other opportunities to launch it since then, but other bigger projects on those particular days took priority. Finally at the Tripoli Indiana launch in early November I was able to use it in a (reinforced) TLP Hawk 23B--flew perfectly as seen below:



BTW, all the procedures mentioned earlier, e.g., backing off the closures, not loading the BP were followed.
 

rocket999

Well-Known Member
Joined
Jun 27, 2009
Messages
75
Reaction score
0
You will be fine storing them for at least a year. Just loosed the aft closure and store them in a zip lock bag. I've fired motors that have been loaded for over 6 months...

BTW, interesting smilies...

:merry-christmas::grinch::hohoho::tree::candy::impatient::happydeer::present:

:)

Sam
 

bobkrech

Well-Known Member
Joined
Jan 20, 2009
Messages
8,352
Reaction score
39
The warranty at https://www.aerotech-rocketry.com/warranty.aspx is only good for 12 hours. I wonder how they picked that number?
A properly designed o-ring sealed motor should have a lifetime limited by the propellant, not the o-rings, insulators or other sealing components. NFPA 1125 mandates a minimum propellant life of 5 years. The single use motors use pretty much the same seal design that the RMS motors use, so that pretty much tells me how good the seal design is.

Bob
 

WillMarchant

Well-Known Member
TRF Supporter
Joined
Jan 15, 2009
Messages
2,467
Reaction score
128
A properly designed o-ring sealed motor should have a lifetime limited by the propellant, not the o-rings, insulators or other sealing components. NFPA 1125 mandates a minimum propellant life of 5 years. The single use motors use pretty much the same seal design that the RMS motors use, so that pretty much tells me how good the seal design is.

Bob
Perhaps someone from Aerotech will weigh in on the rationale for the 12 hour number and the warranty limit of one year for reload kits.
 

stickershock23

New Member
Joined
Jan 18, 2009
Messages
0
Reaction score
-57
I have one recomendation. when you loosen the aft closure and remove the ejection charge. put a piece of masking tape on the motor. that says
"Tighten closure. NO Eject" It's funny what you forget to do when launch day comes. that is some cheap insurance..
 

WillMarchant

Well-Known Member
TRF Supporter
Joined
Jan 15, 2009
Messages
2,467
Reaction score
128
I have one recomendation. when you loosen the aft closure and remove the ejection charge. put a piece of masking tape on the motor. that says
"Tighten closure. NO Eject" It's funny what you forget to do when launch day comes. that is some cheap insurance..
Great advice. Also note any delay change that you made.

Remove the ejection charge THEN loosen the aft closure is probably the appropriate order... :duck:
 

doug_kosty

Well-Known Member
Joined
Dec 20, 2009
Messages
93
Reaction score
16
Thanks for all of the helpful replies. The Aerotech 12 hour warranty is a bit of an eye-opener. Perhaps I should try one of these in a rocket that I am not too fond of. Worst case, I'll just have to get a replacement :D
 

blackjack2564

Crazy Jim's Gone Banana's
TRF Supporter
Joined
Jan 18, 2009
Messages
9,150
Reaction score
1,325
Location
Savannah Ga
Just an educated guess......

.......... a while ago there was a problem with the interaction of some of the delays with the propellant after prolonged storage.
This chemical reaction caused a speed up of the burn time of the delay.

This is why several of the propellants now come with the delay packaged and protected separately. There was mention of this [redline] in the thread that was linked!
By having them assembled the chemical reaction starts immediately to de-grade the proper length of delay time. 12 hrs is the limit by which they have allowed this not to have an effect and by which they will stand by the warranty.

This is not to say it WILL happen, just to say that it CAN happen, and has.

If you are flying electronics it is a moot point. Motor eject is another story.

White lightning, blue thunder,and blackjack have NEVER been an issue with me. I have flown motors [reloads] 10years old and stored loaded 3. I flown single use from 1992 just a few months ago, no issues.
 
Last edited:

dpower

Well-Known Member
Joined
Jan 18, 2009
Messages
1,420
Reaction score
184
My opinion, which I think is consistent with Bob's (I've only used hobbyline), is that it is ok to leave them fully assembled, without loosing the enclosures, for quite long periods of time. If they use the same seal design as the SU motors, which can stay assembled for years before use, I feel I should treat RMS motors the same way. While I don't make a practice of it, I've had hobbyline motors assembled for a few months (usually the winter months), and they have performed fine. After assembling them, I keep stored in small ziplock bags.
 

als57

Well-Known Member
Joined
Jan 25, 2009
Messages
938
Reaction score
0
Well I bought a used AT 29/40-120 case that was loaded with a G71R reload in fall 2008 and burned it in Aug of this year. Was storred in a plastic sandwich bag.

Flew fine except the delay was a couple seconds on the short side. Have seen that before with older Redlines.


Al
 

doug_kosty

Well-Known Member
Joined
Dec 20, 2009
Messages
93
Reaction score
16
Well I have my data point - flew the "loaded one month ago" reloads today and they were just fine. Guess the 12 hour warranty is a bit pessimistic. In the future I will adopt the "loosen the enclosures" technique - that simply makes good sense to me.
 

UPscaler

New Member
TRF Supporter
Joined
Nov 25, 2009
Messages
4,379
Reaction score
379
I had a black jack loaded in my 29 case for about 6 years. It still flew fine, But it was really scary waiting fr the launch.
 
Top