Here's a video of a Czech motor that I static fired last week. I bought it at the NARAM 50 auction.

It's supposed to be an A but, as you can see from the curve, it tested as a B. You can see from the video that the ejection fired part way through the delay. I don't think it aged well over 27 years.

I had a Russian motor that I wanted to fire but I decided it might be better to wait until I could do it outside.

Attached Thumbnails

 

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Bill Spadafora
http://www.billsplumbing.com
billspad@comcast.net bill@billsplumbing.com

and then they told you to go "cool them down" by sticking them in the refrigerator for a while so their performance specs would be A class and you could then use them in the competition.

Now of course by the time they was used, their performance specs were again back above the A class limit, but since they had been tested and impounded while cool , this was completely legal and ethical in their eyes.

It makes one wonder how long this deceptive practice has been going on in FAI competition. Seems to be by design ? eh?


just my 2 cents YMMV



ps by the way Bill. maybe that Czech motor just aged like good wine and got better with time huh?

terry dean

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"Old Rocketeer's don't die; they just go OOP".....unless you 3D print them.

That's no different from boxers gaining and losing weight for a particular weight division. Sometimes taking diuretics to make weight. .....or the racing world using special qualifying tires, then using completely different tires for the race. ...or women wearing makeup and being good until you marry them. ....or

Question for Bill Spad. and others:
With the Old Motor Program information, has there been any data collected on forein made motors. Also if they age as well as domestic motors seem to?
Just curious.

hotrod:

Trip Barber collected some info on various Foreign motors back in 1978 or thereabouts.

Trip says the curent czech delta motors conatin AP/Butyl Rubber.

If they were made from Bp and stored as they should be, I would make a SWAG that they would age like our BP motors. Back in the 60's the Czech ADAST motors were nicknamed "widowmakers" because of their tendency to explode.... they contained all sort of exotic ingredients: AP, nitrocellulose, picric acid,etc etc

I personally don't know if modern APCP have any temperature or humidity related cycling problems like BP does.

terry dean

Attached Files

Foreign Model Rocket Motors 1978.pdf (462.5 KB, 98 views)

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"Old Rocketeer's don't die; they just go OOP".....unless you 3D print them.

just plain cheating?

by your reckining, it would be okay fro me to use humidity and temperature to modify the performance specs of my Estes BP motors for use in NAR competition. Now of course cghanging or modifying the perormance specs of motors used in NAR competition is against not only the NAR MRSC but NFPA regulations too. But how would anybody know I had done such "modifications".....

terry dean

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"Old Rocketeer's don't die; they just go OOP".....unless you 3D print them.

In that article he mentions that the casing gets hot and he wasn't kidding. And it stayed hot for a long time.

I heard that these a made similar to black powder motors with a mixture of the two components rammed into the casing.

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Bill Spadafora
http://www.billsplumbing.com
billspad@comcast.net bill@billsplumbing.com

Estes has also considered making composite motors that way
http://appft1.uspto.gov/netacgi/nph...+AND+propellant

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Dale Greene

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2010 Calder Cup
The Old West
2009 Calder Cup

" Speaking the Truth in times of universal deceit is a revolutionary act. " George Orwell

No, by my reckoning it happens just about everywhere in just about every situation where there is competition...whether it's sports, jobs, or just plain old life. I'm not picking a side of the fence.

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