Aerotech Grain Spacers

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Gee I wonder where they got that idea from. pretty original.
i guess if you can't lead at least follow.

of course thats just my personal opinion
 
As an owner of AT hardware I welcome this product. If they don't violate a patent, more power to 'em. I don't really care otherwise.

Now I think its time we find out who first developed snap ring casings...:y:
 
Actually, AeroTech began using grain spacers in 1991 with the development of the RMS-29/40-120 and its smaller model rocket reloadable motors. Also, Wayne Schaffer of Synerjet first demonstrated the use of grain spacers external to the combustion chamber in the early 90's.

AeroTech invented the reloadable hobby rocket motor in 1990. AeroTech continues to be a leader in the development and implementation of new technologies in hobby rocketry. However, we are certainly not beyond adopting new or recycled ideas developed or reintroduced by others that have merit to consumers.
 
Don't some AT reloads already effectively use spacers? The D and E loads in the 24/40 and the E and F loads in the 29/40-120 are shorter than the space provided, and they use a short cardboard tube to fill the gap...
 
The EGE said:
Don't some AT reloads already effectively use spacers? The D and E loads in the 24/40 and the E and F loads in the 29/40-120 are shorter than the space provided, and they use a short cardboard tube to fill the gap...
Click to expand...

That is correct.
 
Jeroen_at_CTI said:
Seems like the wrong naming for what they are doing. Don't they space the case in stead of the grains?
Jeroen
Click to expand...

I have to agree, If I am understanding this correctly they just added one more piece to the assembly of a reload. since it is being changed internally,
wouldn't they have to be re-certified? it seems like they will just be new motors, not the same motors in different cases.

I think they need to spend more time getting their delays to be the correct time. this would make some happy customers. at a launch in las vegas last weekend I saw 5 rockets almost destroyed because of early ejection. all
of them went about 3 to 5 seconds instead of the "M" (or 10 seconds) they are advertised at. Nothing worse than destroying a rocket because of a bad delay.
 
stickershock23 said:
I have to agree, If I am understanding this correctly they just added one more piece to the assembly of a reload. since it is being changed internally, wouldn't they have to be re-certified? it seems like they will just be new motors, not the same motors in different cases.
Click to expand...

That's a decision for S&T and TMT. Both will, I'm sure, review the changes to any motors they certified, and decide accordingly.

-Kevin
 
I would agree about that comment expect that the very nature of pryo based delays is there going to be problems some times with them no matter how good company is in making them. Its is the very nature of the beast and how they function.

Still not sure why I see so many fliers risk a expensive HPR rocket by using pyro delays. Electronics is the way to go for most all high power rockets and even some mid-power ones. I will usually even pull a very long backup pyro delay charge out of a motor because it could fail by firing early and destroy a altimeter based bird because of failure. I use almost only plugged forward closures to ensure reliability in reloads.

Folks just say no to pryo based motor delays ! Get a good altimeter (accelerometer or baro based) or two and you never will want to go back to pyro delays. :gavel:

Cheers
John ..

stickershock23 said:
I have to agree, If I am understanding this correctly they just added one more piece to the assembly of a reload. since it is being changed internally,
wouldn't they have to be re-certified? it seems like they will just be new motors, not the same motors in different cases.

I think they need to spend more time getting their delays to be the correct time. this would make some happy customers. at a launch in las vegas last weekend I saw 5 rockets almost destroyed because of early ejection. all
of them went about 3 to 5 seconds instead of the "M" (or 10 seconds) they are advertised at. Nothing worse than destroying a rocket because of a bad delay.
Click to expand...
 
Last edited:
How about an E.F.C. ?

rocket1017 said:
I would agree about that comment expect that the very nature of pryo based delays is there going to be problems some times with them no matter how good company is in making them. Its is the very nature of the beast and how they function.

Still not sure why I see so many fliers risk a expensive HPR rocket by using pyro delays. Electronics is the way to go for most all high power rockets and even some mid-power ones. I will usually even pull a very long backup pyro delay charge out of a motor because it could fail by firing early and destroy a altimeter based bird because of failure. I use almost only plugged forward closures to ensure reliability in reloads.

Folks just say no to pryo based motor delays ! Get a good altimeter (accelerometer or baro based) or two and you never will want to go back to pyro delays. :gavel:

Cheers
John ..
Click to expand...
 
shreadvector said:
How about an E.F.C. ?
Click to expand...

Although more accurate than using motor-based ejection, the EFC (which uses a timer) isn't as nice as using an altimeter. With any timer you have to make an accurate prediction of when to deploy the parachute. But, that's not possible because, among other things, wind may affect the rocket's flight. So, using an altimeter makes life easier. It figures out the right time to deploy the recovery system.

-- Roger
 
Uhh not quite right! Check your facts. Frank Kosdon made the first reloadable motors available at least a year or so before Gary came out with them. What Gary did was patent them first and Frank never challenged the patent. I know the history was there when they were released and flew them.

Cheers
John ..

ATIPR said:
Actually, AeroTech began using grain spacers in 1991 with the development of the RMS-29/40-120 and its smaller model rocket reloadable motors. Also, Wayne Schaffer of Synerjet first demonstrated the use of grain spacers external to the combustion chamber in the early 90's.

AeroTech invented the reloadable hobby rocket motor in 1990. AeroTech continues to be a leader in the development and implementation of new technologies in hobby rocketry. However, we are certainly not beyond adopting new or recycled ideas developed or reintroduced by others that have merit to consumers.
Click to expand...
 
rocket1017 said:
Uhh not quite right! Check your facts. Frank Kosdon made the first reloadable motors available at least a year or so before Gary came out with them. What Gary did was patent them first and Frank never challenged the patent. I know the history was there when they were released and flew them.

Cheers
John ..
Click to expand...

Hi John, Gary here. I just got off the phone with Frank K. to check the facts. Frank confirms that he first publicly displayed and sold reloadables during LDRS in Hartsel, CO in 1990, and they were tested on the AeroTech test stand the following February. AeroTech displayed and flew RMS motors at a Black Rock launch a few months earlier, and also sold motors at the Hartsel LDRS in 1990. AeroTech began designing the first reloadables in 1988.
 
Last edited:
Garoq said:
Hi John, Gary here. I just got off the phone with Frank K. to check the facts. Frank confirms that he first publicly displayed and sold reloadables during LDRS in Hartsel, CO in 1990, and they were tested on the AeroTech test stand the following February. AeroTech displayed and flew RMS motors at a Black Rock launch a few months earlier, and also sold motors at the Hartsel LDRS in 1990. AeroTech began designing the first reloadables in 1988.
Click to expand...

Was Frank responsible for the reloadable motor that we found at the MIT Rocket Society test cell in the late 1970's ? It was rumored to be from the 1950's or 1960's and had an unscrewable aft closure. I don't remember any additional details except that Hyong Bang (yes, that was his real name) produced some propellant to test in it (around 1979 or 1980) that actually detonated when ignited - and he did not have the aft closure in place!!! it made quite a mess and thankfully he was standing by the quartz window that was built into the steel blast chamber. It bent the steel door and the spring loaded roof panel.

Safety first.
 
I hope 29mm versions come out soon. I'd love to be able to fly G loads in my 29/180 case.
 
shreadvector said:
Was Frank responsible for the reloadable motor that we found at the MIT Rocket Society test cell in the late 1970's ? It was rumored to be from the 1950's or 1960's and had an unscrewable aft closure.
Click to expand...

There were some JATO rockets (back in the 1950s or earlier?) that assembled somewhat like our reloadable rocket motors. I'm not sure, however, if they were designed to be reloaded and re-used after use or if the design was to make storage and assembly easier (the propellant could be stored separate from the motor casing). I suspect the latter.

Aerotech's patent (1993) doesn't mention any prior patents that sound much like a truly reloadable solid rocket motor.

A patent for a Kosdon-style motor was issued later (in 1994) to Charles Mund. It also doesn't mention any earlier patents for a reloadable solid motor. Interestingly, though, it references an Aerotech ad in Triploi's Tripolitan magazine.


-- Roger
 
Jeroen_at_CTI said:
Seems like the wrong naming for what they are doing. Don't they space the case in stead of the grains?
Jeroen
Click to expand...

My question is why is a Ph.D spending time wondering about what AeroTech or its representatives calls them, and calling attention to it on multiple forums? Perhaps to try and make them look like they don't know what they're talking about? :rolleyes:

Grain spacer = takes up space that was occupied by one or more missing grains. Also called grain adapter in the AeroTech model rocket RMS reloads.

Case spacer = takes up space ahead of a shorter motor case in a longer motor mount tube with a motor block. Also called motor adapter.

I don't know, call them tubes or pipes or whatever you want, YMMV.
 
WillMarchant said:
Could somebody please supply a URL to information about the thingamajiggers? I don't see anything on the https://aerotech-rocketry.com/ site. Maybe I just missed it... Thanks in advance!
Click to expand...

Sounds like it's a new product which AeroTech is just starting to show.

I'm betting Gary and company will make an announcement when they're released and available in the market.

-Kevin
 
jadebox said:
Aerotech's patent (1993) doesn't mention any prior patents that sound much like a truly reloadable solid rocket motor.

A patent for a Kosdon-style motor was issued later (in 1994) to Charles Mund. It also doesn't mention any earlier patents for a reloadable solid motor. Interestingly, though, it references an Aerotech ad in Triploi's Tripolitan magazine.
Click to expand...
Interesting reading material. The Chuck Mund patent application says it was submitted on 05/03/1991 while the ISP patent application says it was submitted on 05/20/1991. So what determines who was first — who submitted first or who was granted first? I have to imagine the real first was who showed it to the public first, but I don't know how you document that. Maybe it was Hyong Bang like Fred said. All this while, I thought it was Jerry Irvine. :)
 
Last edited:
ddmobley said:
Interesting reading material. The Chuck Mund patent application says it was submitted on 05/03/1991 while the ISP patent application says it was submitted on 05/20/1991. So what determines who was first — who submitted first or who was granted first? I have to imagine the real first was who showed it to the public first, but I don't know how you document that. Maybe it was Hyong Bang like Fred said. All this while, I thought it was Jerry Irvine. :)
Click to expand...


Hyong Bang did not invent anything related to the casing, he found it (it was at least a decade old) and simply mixed what he thought was propellant to fire in it.

Google intellectual property and patents and/or search Wikipedia.
 
troj said:
Sounds like it's a new product which AeroTech is just starting to show.

I'm betting Gary and company will make an announcement when they're released and available in the market.

-Kevin
Click to expand...

We will be making a public announcement soon.
 
ddmobley said:
Interesting reading material. The Chuck Mund patent application says it was submitted on 05/03/1991 while the ISP patent application says it was submitted on 05/20/1991. So what determines who was first — who submitted first or who was granted first? I have to imagine the real first was who showed it to the public first, but I don't know how you document that. Maybe it was Hyong Bang like Fred said. All this while, I thought it was Jerry Irvine. :)
Click to expand...

The US operates under "first to invent" versus "first to file" rules, which is why companies are so keen on their R&D departments keeping lab notebooks and other documentation.
 
As I remember history (which, I admit, could be wrong) in the very late 80's, early 90's, the talk was that Aerotech was venturing into the realm of EX due to reloadable casings and the other motor manufacturers (single use) were against it. Now everyone is trying to take credit for it.

It seems to me that it was one of the motor manufacturers that was responsible for initiating the BATFE"s interest in regulating the motors in the first place over this issue.

Feel free to correct me because, again, that is history as I remember it. :)

As far as the grain spacers when can I order them? I like the idea of being able to go to a launch with motors I have built the night before and flying two I211's without having to buy another 38/480 case.

Although, I have heard that the one who dies with the most motor casings wins. ;)
 
So do these need to be Certified? it is changing the configuration of the reload.

How much do they cost?

Are they available in only 1 grain configuration? or can you use two of them?
If you use two will they be available separately or will it be another completer 3 piece system?

If used in other manufacturers cases will they cover the warranty if one fails? or will Aerotech?
 

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