New AT motor technology

implemented.

times...

I'm sure they will work something out. IThe concept has already been approved by NFPA, which is the real issue.

"certified"

Why would anyone keep using the same case over and over, when they get a new case every time they buy a pack of loads? Your argument doesn't make sense.

Besides, if anyone actually was stupid enough to keep using the same case until it catoes, the worst that will happen is they have to buy a new rocket.

You can't buy grains without a case, so there would be no reason to reuse a case more than three times. It doesn't mean someone won't try it.

I'm sure RCS will fire these well beyond three uses during testing just for simple liability reasons.

Brian Elfert

It was already allowed within NFPA "model code" language. Synerjet had motor kits many years ago already.

The only "mods" to NFPA were NOT done by NFPA itself or even overseen in any substantial way by NFPA. They were made by the members of the sport rocket caucus and submitted for rubber stamp to the NFPA-pyrotechnics committee which is yet another group of industry reps.

NFPA rents a room and sells books.

You really need to update your false language Ray.

Because you can. My kid got up to OVER 80 firings on a SINGLE NOZZLE the other day.

Correct. Therefore no rule against it is needed.

Unless you just love rules for their own sake and the collateral damage just doesn't bother you one little bit. Like TRA leaders for example.

Jerry

If anything, as others have said, you're far more likely to lose the case and end up with a surplus of grains. However, in this case you might just have another LUR case you've fired three times (and kept for whatever reason) kicking around and decide to use that instead...

Indications from Gary on TRF are that there will be a very high safety margin on these cases, so that shouldn't cause any problems. Clearly the molded cases are over-engineered sufficiently that the LUR concept is possible. I think it makes sense - if the SU casing will hold up reliably to say 10 firings, ditching it after 1 firing is wasteful. If the casing was so affected by one firing that it was unusable next time it would be another matter.

So what is the mean number of flights before casing loss?

What is the average number of reload kits sold per casing sold?

Alan

Great way to practice reloads as well. If you FUBAR a reload in an expensive casing, you are left with the only recourse of buying a new casing. FUBAR a reload on a limited reuse casing (ie what is mentioned above) its not as big of a catastrophe -> except maybe for the rocket it was in >_<

It is a very good system that I believe will self-police so well it may even justify selling reload packs separately if the total flight volume is high. This is because the "typical" case life exceeds 3 by multiples of 2 or 3.

Jerry

In article snipped-for-privacy@4ax.com, Alan Jones at snipped-for-privacy@nospam.mchsi.com wrote on 3/15/05 9:01 AM:

I don't know of anyone that collects that type of information.

You would need to know Dr. Rocket's unit sales to answer that question.

Gary

Precisely.

Or it sells another new set :)

ecology :)

Jerry

Now that Gary has responded...

That is a bell curve. It is associated with rocket power-to-weight. For example you typically do not lose low power or BDR.

But you do lose high alt/performance cases.

So the key is to have a BDR for each motor mount size you might use in a HP rocket.

I would guess 10:1.

And only about 50% of motors sold are flown. Alot are "collected".

Jerry

I can't speak for everyone, but I've made about 200 RMS flights and lost ONE casing. Came close a few other times, due to trees or whatever, but all eventually got recovered except the one.

A distorted number. Rocketeers may have a lot of grains they haven't flown yet, and / or several casings they haven't used yet. I have both!

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Up to a point...

Perhaps having the casings available separately would be a good idea if you were unlucky and lost several you'd have quite a backlog of reloads and no casing. Same thing if (for whatever reason) the motor CATO'd.

It seems a nice idea, but its a bit less black and white than SU/RMS. Its probably just a case of applying common sense - if its rated for 3 firings and you're about to fire it for the 9th time, you shouldn't be surprised if your rocket ends up in pieces!

SU: use once, throw away RMS:

DO RELOAD USE CLEAN UNTIL loss OR cato

Ecology, Economics and Engineering :)

It is still just another RMS to me, albeit a cheaper one. _Especially_ if they sell the reload packs separately...

It will still be interesting to see how it well they do.

~ Duane Phillips.

Seeing the "breaking point" of these cases could actually become a "contest" of sort! "I few this case x times, even though AT only says 3!". It may not be you Ray, but understand that you're view isn't the same as everyone...)

It could not just be a cato if the case is used 5 or 15 times when it's only certed for 3.. If the cato resulted in other damage, what's the insurance impact? Let's say the cato resulted in a grass fire for example. (as I've seen in AZ, with a few that have been nasty.. And this will be a bad summer for fires here, based on the rains in the spring....) No one hurt, but the guy that owns the field files a claim as he lost 2 acres of "whatever".... "well, I think I used that case less than 10 times....."

You NEED bad news to live, don't you?

Buy a clue, Jerry. Even Economists know that a mean is not a bell curve.

MOre to the point, rocketeers flying expensive reloadable cases tend to wimp out and only fly low and slow. :(

That looks more like a mean ratio than a bell curve.

More lies. 90% of all statistics are just made up.

"A lot". By "collected", do you mean confiscated by the authorities?

Alan

NFPA writes regulations which become law when adopted by states and municipalities.

The cases can handle additional firings, so using up a couple of spare loads is no biggie.

launch one

getting

Sure, there's always someone who will find a way to do something stupid with anything. That's no reason to keep a good product off the market.

"whatever"....

If you're that worried about it, don't permit them at your launch.

You know what? You keep saying this false statement. You keep getting corrected by people with first hand experience. You refuse to change.

This is one of the many reasons you are characterized as a moron.