Just seems to me that the date of cert expiration is an important thing. Kind of like "buy before" and "use before" dates on food...
But in this case, it also allows an RSO to determine if a motor is still certified or not, or if it was manufactured after the cert had expired.. I guess this assumes that motor certs still expire, as manufacturers probably didn't like to recert every 3-5 years (or when they start manufacturing in Texas, or Utah! - Remember the Texas J350's!)
What about manufacturers that go out of business? Do they stay on the certified list forever?
A refill is theoretically about the same price here, but then there is the extra "fixed charge" of another $15, plus yet another $30 for "delivery" (to the local depot - don't ask) - plus $60 annual rental, plus account charges, plus VAT - works out about $150 for tank rental and one refill per year.
That's roughly typical of the large suppliers, who only rent cylinders - the smaller boys who sell them usually end up costing more overall, and you can end up with a cylinder that no-one will refill.
By making the oxygen on demand, by catalytic decomposition of sodium percarbonate. This is readily available here as "oxygen" laundry bleach. The catalyst is made from rusty "brillo" pads (steel wool cleaning pads) and the insides of a zinc-carbon dry cell battery (or some manganese IV oxide, if you have any handy).
The equipment is made from PET drinks bottles and a few other bits-and-bobs, and should cost about £10 including a containment/safety shield, as exploding PET bottles are nasty. The percarbonate costs 52p per launch.
This is entirely legal, eco-friendly, and if done correctly it should be at least as safe as if not safer than using high pressure steel tanks.
But I don't know if it will work. The simple theory is okay, but the required rate of flow is higher than I anticipated, and I still have to do some experiments, detail design work, failure analysis and so on.
And would be illegal here in the UK.
More, you can't simply get a tank, test it, and then use it - you have to be able to show everything from the raw material manufacturers' test documents to the tank manufacturer's EU conformity declaration.
No, TMT is a testing authority and their responsibility is to provide accurate unbiased information on all of the motors they certify. They are failing in that duty. Either they need to do the job, or pass it on to some other body that can do it right.
Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!
Do you have any credible evidence of this? You have said it MANY times in that past and have NEVER presented any credible documentation to PROVE IT!
Try posting something rocketry related for once. Everyone is tired of your many years old personal vendettas. If you can't do that, at least make up some new stories.
Determining this from PUBLIC TMT output is also practical and has been done right here on rmr. Feel free to review the log. Many PROVEN examples in there.
Again your being myopic about it means nothing. Less than nothing actually.
I am not demanding you take my word for it, but my word is affirned by fact.
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