At least that's been MY experience... in many things in life-- so I guess rocketry should be no different...
Here's a few select responses in the thread in question over on YORF...
ghrocketman
I only have a handful of the old Centuri 13mm B's left....wish I had a bagful.
I'm of the opinion that ONCE a motor is certified it should NEVER lose certification for age/out of production.
Motors should ONLY lose certification if for safety reasons.
Better yet, DUMP the certification process all together and ELIMINATE it's requirement.
It's as moronic as requiring blends of R/C glow fuel be 'certified'.
uke strawwalker
Quote:
Originally Posted by ghrocketman
I only have a handful of the old Centuri 13mm B's left....wish I had a bagful.
I'm of the opinion that ONCE a motor is certified it should NEVER lose certification for age/out of production.
Motors should ONLY lose certification if for safety reasons.
Better yet, DUMP the certification process all together and ELIMINATE it's requirement.
It's as moronic as requiring blends of R/C glow fuel be 'certified'.
Exactly... I've thought the same thing for YEARS...
If you're talking about "contest certified" I can see the purpose of wanting a 'readily available" motor, but then you're talking about an "approved motor list" which is not the same thing as "safety certified".
Contest certified is really only applicable to the tiny minority of rocketeers that actually engage in contest flying... (which if that's your bag, more power to you, but the "average rocketeer" could really care less...) Like I said, that being the case, then have an "approved motor list" for contest flying, and remove motors that have been out of production or that aren't readily available for contest flying, and leave it at that.
Safety certification, once obtained for a given motor and issued, should NEVER be revoked unless it's statistically proven that a given motor is unsafe, ie prone to go "BOOM" or have some other sort of failure at a statistically unacceptable rate.
The fact that motor certifications are removed once a motor becomes "too hard to get" for contest use is really an inconvenience to the vast majority of the rocketry community not engaged in competition. If it were merely an inconvenience, it wouldn't be so bad, however, flying "uncertified" rocket motors is grounds for refusal to pay the claim should anything happen during a rocket flight causing an injury or damage on the ground, exposing the rocketeer and club/launch site to undue liability, which is why flying "uncertified" motors is usually discouraged or not allowed. It's foolish, but it's how "the system" works.
It's a system that needs to be changed.
Later! OL J R
Royatl
As I recall, the original Safety and Contest certifications had certain performance parameters, like Safety was within 15% of stated thrust and impulse, and Contest was 5% within some amount of standard deviation.
Those went away sometime while I wasn't paying attention. Apparently, DuPont's black powder, which Estes depended on, suffered varied quality and efficiency in the 70's and 80's and Estes found it difficult to hold its motors to the same performance parameters as before.
So NAR certification simply meant they were consistent, worked properly and the company that made them could provide customer support (and a liability chain). Contest certification then became essentially the subset of motors that were commercially available to most competitors.
The liability chain is, apparently, the sticking point to making initial certification permanent.
Date codes on motor labels is probably another problem. If you say, we certify the Jones A7-5 motors made between 5-2003 and 8-2008, but no others, you've got to have the date stamped indelibly somewhere on the motor. But motor manufacturers have been inconsistent about that at best. Estes went to that 1970=A, etc system for years, then for awhile a code probably based on which Mabel it was made on, and marketing says some people think of the date as an expiry date. Aerotech had some octal system or some such, and for a long time they were printed on the ejection charge cap, so you couldn't tell anything about the motor after operation. And that's ignoring the whole reload situation.
So, what about doing away with certification totally? Well then, how do you count on anything the manufacturer tells you? You might trust Estes, but why? Why would you trust Aerotech? CTI? So you build or buy your own test stand and check them yourself, but that's usually impractical when you're talking about a K motor or larger, unless you've got money to... well, you know.
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Roy
astronwolf
Back in the day, they needed something to distinguish model rocket motors from fire crackers. IMHO, we still do today. So we enjoy the benefit of having a certification process.
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-Wolfram v. Kiparski
Chas Russell
Wolf noted: "Back in the day, they needed something to distinguish model rocket motors from fire crackers. IMHO, we still do today. So we enjoy the benefit of having a certification process."
Oh Wolf, you say the nicest things. Seriously, it is what the G. Harry, the Model Missile Association, Estes and others had as an uphill battle to change or revise fireworks restrictions to allow model rockets to be flown. The MMA became the NAR and testing standards were established to certify motors to convince fire authorities to allow model rockets.
In my home state of Ohio, in my home town we had a fire marshal, Fred Long, who became a model rocketeer and advocate, supporting the NAR and the Columbus Society for the Advancement of Rocketry. I served on the NAR Standard and Testing Committee in the late '60s and early '70s (then in the Air Force much bigger motors).
Motor certification is what keeps the authorities in check along with the Safety Code. There are those who think they should be allowed to do anything they want, but we are always one "Oops" away from additional restrictions. At the least, bad press. We had a saying in the Strategic Air Command that you could have all the "Atta Boys" in the world, but it only takes one "Ah Sh*t" to wipe them all out.
Certification is what keeps the wolves away... Sorry Astrowolf...
Chas
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