I'm new to rocketry. I am looking to purchase a motor system and I am very confused. The Aerotech hardware and motors seem to be a lot more expensive then USR motors on ROL auctions. Is there a reason for this? Am I getting myself in trouble if I purchase the USR hardware? Will it work with Aerotech reloads? Does anyone know why the cost difference is so much? If I purchase Aerotech am I getting into trouble because they are going bankrupt?
Bayourat
The Simple answer: USR motors are no longer recognized by either national Rocket clubs: Tripoli
JD
That's a very good question. To state a different way
Is the certification issued by TRA/NAR for the hardware, propellant load, or both?
Careful, if it includes the hardware, how does Dr. Rocket hardware fit into AT certifications?
Bob
It is only fair to compare retail for retail at the manufacturer website.
As such the diferences are minimal.
It is also important to consider availability. Some brands are available through more outlets, or more locally, than others. To a consumer it does not matter why that is the case, only that it is.
USR closures and AT closures are interchangable with both their cases (except AT 38-240).
The loads have to be designed for the particular combo you have selected. That is critical.
Both are "mostly very reliable".
Jerry
The certification submission from the manufacturer specifies the hardware that the reloads are to be assembled in. The "Aerotech" and "Dr. Rocket" branded hardware components are made in the same machine shop (the only difference is in the final finish and labeling method), and are considered perfectly equivalent and interchangeable, even by Aerotech and TMT themselves.
-dave w
Whitney, is that you?
- iz
Bayourat wrote:
OK, let's see now... AT needs money...hmmmmm
How about I contract with AT to make me a line of single use motors in the range of F25, F50, G40 and G80. To be labeled under my small business.
Since "the only difference is in the final finish and labeling method" would they not be certified/certifiable by me?
As the contractor, I am not responsible for any manufacturing permits, shipping permits, etc.
Bob
Dr Rocket makes the cases under license from Aerotech, as well as using the same machine shop. That is why they are certified by TRA and NAR for use with Aerotech reloads.
Brian Elfert
NAR currently allows AT to do that for PML, RV and even USR when Gary will cooperate.
although there are many requirements in NFPA 1125 regarding motor casings, most are the responsibility of the manufacturer. However, a certifying organization is responsible for the following specific tests of motor cases:
I believe PML was doing exactly that (with 3 of the four specific types they mentioned, as a matter of fact), and selling them under the "PML Thrusters" brand.
-dave w
Does PML have a LEMP and EX numbers in the name/address of PML?
If not the please exxpla> > How about I contract with AT to make me a line of single use motors in
So was Apogee. Remember the F10 Slow burn. (I loved that motor.)
Bayourat
PML doesn't need a LEMP, as they are not the manufacturer. They are simply dealing motors made by Aerotech (and placing their own label on them). The motors have EX numbers, obtained by Aerotech.
I see no correlation between the two situations. Aerotech is an operational company that will stand behind its products. Aerotech sumbitted the motors that PML is selling for TRA/NAR certification. Aerotech has all appropriate licenses and PML makes no secret of where they get their motors. PML is not telling us to ignore that man behind the curtain.
- JT
Hmmm... so US Rockets doesn't need a LEMP, as they are not the manufacturer. They are simply dealing motors made for them by ACS and placing their own label on them. The propellant in those motors has either an EX number (or an acknowledgement of the lack of "explosive" hazard requiring same, depending on size), obtained by ACS.
Seems like a perfectly parallel situation to me...
-dave w
Aerotech considers Dr. Rocket hardware equivalent to their own.
-- Joe Michel NAR 82797 L1
That is a contractural issue between PML and AT. If JI wants to contract with a company to have his motors made for him, and the contract has him "stand behind his products" then why is it anybody elses business who is making them? Why can't JI submit them for certification?
Bob
Bingo! Now for a little substitution on your words:
Does the above cut and paste not shed some light?
Irrelevant to the certification process.
certification.
Does is matter who submitted them for testing? If so, please explain why
As does ACS. Jerry is for all intensive purposes a dealer. A dealer who would like to get his product certified for sale.
telling us to ignore that man behind
That is irrelevant. Chick-fil-a makes it a very big secret where they get there chickin from. 90% of the goods you buys were OEM'd from someone who all parties involved work hard to keep nameless.
The difference is that in PML's case, the manufacturer (ie Aerotech) presented the motors for certification, not PML, and in doing so also presented their LEMP, etc... If ACS (which I thought didn't exist any longer) were to send motors in for certification, and show their licenses, etc. then JI, USR, or anyone else could stick their labels on them and sell them. It's simple, the certifying authority (TRA, NAR, or CAR) needs to be in direct contact with the manufacturer. I can't imagine why a proper manufacturer would refuse to do this, as it would then allow them to make money.
- JT
Yes, it matters to TMT as per rule 2-4.0 "Motors shall be accepted for testing only when submitted by their specific manufacturers. Individuals, distributors, agents or other interested parties not directly involved in the specific operation of the motor manufacturing company shall not be permitted to submit, or be a part of the motor certification process." I believe that NAR and CAR have similar rules.
I've only been around the HPR hobby for six or seven years and I don't know the history of ACS. What I do know is that there has not been any mention of a company called ACS in the rocketry mags or online or anywhere that I know of, except for the document from 1986 that JI likes to show people. A LEMP is not a company asset that can be bought and sold and I haven't seen anything that leads me to believe that ACS is still in the business of making motors (or making anything).
- JT
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