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TheAviator

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I was just wondering if anyone had flown a rocket motor that was not made in the U.S. or Canada (sorry CTI!) One bunch that specifically comes to mind is the Delta motors that I believe are made in the Czech Republic. What kind of thrust profiles/physical sizes do we not get the joy of sending into the wild blue yonder of the USA? All sizes and all impulses welcome!
 
Yes, I've flown motors from Delta, Ultra and Sky.

kj

I was kinda hoping for a little more info than that. How do they compare to the motors we have here (Estes/Quest/AT/CTI/etc.) and where are they made?
 
I'm on the US Team and have used many of the Delta motors. Their construction is really nice. I'm not sure what they use for the nozzle end but it's a very smooth material that's formed really well.

The cardboard casing is thinner than Estes motors and is more prone to blowouts or burning. I initially had some problems with my Mylar tape strangling the motor during flight because it shrunk from the heat. Now I use paper tape :)

I can't remember right now what designation motors I've used but many of them are low thrust with a long duration for their particular motor class. Makes sense as many of these were designed for competition where the rockets are extremely light weight and where slower airspeeds equals lower drag.

When I first used them my liftoffs seemed really slow in comparison to the Estes 13mm A motors. They even seem to sputter a little bit, but boy do they just keep going. The thrust duration isn't that much longer than the comparable Estes motors, but it sure seems like it. I did have one defective Delta motor in Spain during the WSMC's but they did allow me to refly my damaged rocket.
 
here's a photo. This one's an A2-5. Talk about low average thrust!
 
here's a photo. This one's an A2-5. Talk about low average thrust!
Is it really that much lower in thrust than an A3T? I wonder if the big advantage of the Delta motors has something to do with their smaller diameter and lower mass? That 5-second delay would really come in handy in some situations, too, I'm sure.

MarkII
 
Actually, I was thinking in mind more of an A8 when I was doing the comparison. But I think the Delta motors probably have performance characteristics that are slightly different than their noted designation. Their duration seems much longer than even the A3.

Indeed, the casing weight really helps with performance. It is a little difficult to fit a standard Estes ignitor in the nozzle. I had to carefully file any excess pyrogen off the tips of my ignitors in order to get them to fit.
 
Actually, I was thinking in mind more of an A8 when I was doing the comparison. But I think the Delta motors probably have performance characteristics that are slightly different than their noted designation. Their duration seems much longer than even the A3.

Indeed, the casing weight really helps with performance. It is a little difficult to fit a standard Estes ignitor in the nozzle. I had to carefully file any excess pyrogen off the tips of my ignitors in order to get them to fit.

The real average thrust for an Estes A8 is 3.18 and a Quest A6 is 4.15 or 5.17 depending on where it was made. Assuming the average thrust of the A2 is really around 2 it should perform closer to the A8.
 
I was kinda hoping for a little more info than that. How do they compare to the motors we have here (Estes/Quest/AT/CTI/etc.) and where are they made?

Delta and Ultra are made in Eastern Europe. I want to say the Deltas are Czech and the Ultras Ukranian. Sky is from China.

The A2 motors are 10mm or so so smaller and lighter than the 13mm Estes models. They don't have nearly the initial impules of the A3.

From observing the higher impules classes, we have the edge in motors from C on up.

kj
 
Is it really that much lower in thrust than an A3T? I wonder if the big advantage of the Delta motors has something to do with their smaller diameter and lower mass? That 5-second delay would really come in handy in some situations, too, I'm sure.

Yes, the thrust is lower. I do not have the thrust curve info, but it is lower. Slightly higher than the old Apogee micros. I had a prototype S4B (B powered) boost Glider that held up to an Apogee B2 fine but shredded on a Delta B2...but just barely shredded, as the B2 boosted a little bit faster and that bird was on edge (fortunately I found a good light way to beef it up just enough). That same model would definitely shred on a B4, and even if it did not (it would), it would not boost as high either.

I mention B’s when some others have mentioned A’s, since years ago some of the events like copter (S9) and B/G (S4) were B power and more recent years those old B events dropped to A power. But effectively the main difference from the Delta (or old Apogee) B2’s were casing length, and propellant length. The thrust curves were much the same shape except the B burns longer than the A (just like the B6 and C6 have the same thrust curve shape, the C6 just burns longer than the B6).

Anyway, multiple benefits of those motors, DO keep in mind that the models they power weigh grams, not ounces. A model over an ounce liftoff mass is rare, maybe some copter models and even those few are not over 28.3 grams by much.

The lower thrust gives a more efficient boost compared to a higher thrust boost.

The lower thrust means less boost stress, so the model can be designed and built lighter, structurally.

The lower engine casing mass helps in the events like Parachute, Streamer, and Helicopter. My original 2002 S9B copter models, which could fly for FIVE MINUTES dead air on a Delta B2 motor, cannot get two minutes dead air on an Estes 18mm B engine, they are really dogged-down by way excess engine mass of an 18mm B and of course do not go quite as high either.

Also, those engines are made VERY close to the Newton-second limit. Such as 2.4 to 2.45, maybe even 2.49 n-sec. By contrast, a “hot” Estes 13mm A tends to be more like 2.3 n-sec, and thru the years I think they have dipped under 2.0 at times.

As for the 5 second delay, yes, that can be useful. So can a 6 second delay, or 3 second delay, or 7 second delay, or 2 second delay, depending on the needs of the models. The thing is, Delta will make them to order for whatever time delay that a team or group wants to order. Of course, long ago, Estes used to have A3-2 and A3-6 engines, plus of course A3-0 and A10-0 booster engines, to only mention 13mm A’s.

As for the Deltas, it seems they are hand--pressed, not made by machines. They use some sort of high energy propellant that is something above Black Powder, but below composites as we think of them (someone once called them a “pressed composite”. But I do not think that means there is APCP in it, but I do not know what is in it). Whatever is in them, would make it extra-difficult to get them an explosives EX number to import for sale here. The casing, whatever it is, is just sufficient for doing its job. Part of it burns away so there is apparently less casing mass after bring than before burning, but I do not recall if anyone has dissected an unfired one to see just what the masses are for the casing, and nozzle, and then the propellant/delay/ejection. While with an Estes or Quest BP engine there is very little erosion of the casing by comparison. Perhaps it is that the casing wall is thinner by proportion than for BP motors, so that also helps make the motor especially light, that is it not just the propellant.

The closest thing to those that were in the US, was from 1995 (or 96) to 2001(?) when Apogee made 11mm micro engines. And then literally overnight stopped making them. They were heavier and longer than the Deltas, and a hair bigger in diameter, but they were definitely the next best thing. Available from 1/4A thru B power. And yes, those were an attempt to copy the Delta motors, but the Apogee micros used BP propellant and conventional casing material.

- George Gassaway
 
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...As for the Deltas, it seems they are hand--pressed, not made by machines. They use some sort of high energy propellant that is something above Black Powder, but below composites as we think of them (someone once called them a “pressed composite”. But I do not think that means there is APCP in it, but I do not know what is in it). Whatever is in them, would make it extra-difficult to get them an explosives EX number to import for sale here...

- George Gassaway
George

I have to assume these competition motors are made to order for FAI events, certified by the country's national FAI organization, and hand carried to the events (or illegally shipped) because the rules for shipping rocket motors in Europe aren't any different in Europe than in the US.

These motors are limited production, limited interest items. It's simply not economical to get the propellant characterized for common carrier shipment. In Europe, these motors would need CE approval for commercial shipments and the last time I checked it cost way over $20,000 to get rocket motors and propellants UN characterized and CE certified.

I doubt that the motors use a special high energy propellant. You can change the performance of "BP" significantly by changing the formulation composition, particle size, press pressure and nozzle throat size. I think their made more like custom, hand-load ammo, precisely measured and processed, and then well-characterized so that they all perform identically.

Bob
 
Which is EXACTLY WHY the FAI / WSMC does not fly those classes and stays in the lowest impulse ranges !

I respectfully disagree. The S8 RC Rocket Glider event is flown at D impulse (Juniors) and E impulse (Seniors), and S7 scale models are generally flown anywhere from D-G impulse, so there are events where higher impulse motors are flown. The performance events are not flown at higher impulse levels because that would make the models essentially unrecoverable.

The FAI did bump the impulse level for the tube performance events from A to B for the 2002 Championships cycle, but moved it right back down to A impulse due to the staggering duration times and the associated recovery challenges.

James
 
The Ultra's are make in Serbia; the MRD are made in the Ukraine for Russian and Ukrainians. None have been certified to NFPA 1125 standards. Tony Reynolds had a USDOT SP at one time to allow for some of these , particularly the Deltas to be imported. Supposedly.. The NAR has a bogus compliance program allowing them for use by their NAR FAI Team members here in the USA. .


https://www.nar.org/cabinet/minutes/narminutes200608.pdf

Note Compliance Program initiated by Trip Barber and Ted Cochran

https://www.nar.org/cabinet/minutes/narminutes200803.pdf

They are usually just smuggled back into the USA undeclared. Been going on for 40 years now at least.

IF I was to make the exact same motors, the NAR would sic the nearest State Fire Marshal on me and try and get me arrested, because here in the USA an individual can't make and sell his own personally produced model rocket engines without NFPA 1125 compliance and certification. But because the NAR wants engines for its members to use so they can have sufficient practice with the real motors in pseudo-FAI competition practices here, they allow their import and use, and distribution in this country. Under the radar.

see Motor certification by NAR President Trip Barber:
https://www.nar.org/pdf/Section4.pdf


https://www.nar.org/pdf/2010 March BOT Minutes.pdf


They are sold to one another at NAR sanctioned meets like at NARAM and some have been shipped through the US Postal system with no paperwork.

Your NAR at work for you.

Oh yea, now that the NAR is flush with cash that they are literally giving away, why not spend some of that hard earned money and make these motors legal once and for all?

Let the flames and denials and personal demonization begin.

Terry Dean
 
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Bob said:

"I doubt that the motors use a special high energy propellant. You can change the performance of "BP" significantly by changing the formulation composition, particle size, press pressure and nozzle throat size. I think their made more like custom, hand-load ammo, precisely measured and processed, and then well-characterized so that they all perform identically."

Bob, while I agree with 99.9% of what you say here, the Deltas were made by a person who was , one Jiri Taborski, who probably used military grade or ammunition grade propellants, as he had a background in the Czech paramilitary.

So it could be pressed smokeless powder for all we know. And that's the problem : these "motors" aren't really "certified" to NFPA 1125 standards nor do they have USDOT EX numbers or paperwork, yet the NAR allows their use by NAR Presidential fiat which allows for the effective overruling of NFPA 1125 in this country. Since when did the NAR get the power to overrrule NFPA regulations in a state for its members? I don't think the NAR was ever given that authority or power by any AHJ.

If one of these motors blows somebodies eye or hand off, whose liability will it be? Jiri Taborski in the Czech Republic? Good luck trying to sue him from here. Or is it more likely the NAR will be sued into oblivion for allowing these motors to be used by its members? You can do the math on that one.



Terry Dean
 
They are sold to one another at NAR sanctioned meets like at NARAM and some have been shipped through the US Postal system with no paperwork.

Can't say I've ever bought one at a NARAM or any other sanctioned meet. I have paid for them as part of a WSMC team purchase (twice even).

I have hand delivered them to team members (who also paid for them as part of their participation in a WSMC) and have even flown one or two as practice at private launches.

Why the axe grinding Terry?

kj
 
Just some info from someone actually involved in needing to get my hands on some of these motors.

The last motors I bought came from Tony Reynolds who distributed them at the Capitol Cup. Tony specifically drove from Texas, rather than fly, to Virginia because he had those motors with him.

I bought my motors from Tony but was unable to bring them home right away because I flew to VA. So I left them there and had Mark Bundick drive them back home after he attended NARAM the next week.

I provided some motors to my teammates in Minnesota after they drove to ILL to pick them up. So they got their motors via Texas, Virginia, and Illinois rather than taking any illegal shortcuts.

Gosh, it would sure be nice if we did what you said we were doing. Otherwise, a lot of us could make our lives easier if we just shipped these motors illegally. Instead, the motors I'm aware of have painstakingly been driven around the country to supply teammates.
 
Bob said:

"I doubt that the motors use a special high energy propellant. You can change the performance of "BP" significantly by changing the formulation composition, particle size, press pressure and nozzle throat size. I think their made more like custom, hand-load ammo, precisely measured and processed, and then well-characterized so that they all perform identically."

Bob, while I agree with 99.9% of what you say here, the Deltas were made by a person who was , one Jiri Taborski, who probably used military grade or ammunition grade propellants, as he had a background in the Czech paramilitary.

So it could be pressed smokeless powder for all we know. And that's the problem : these "motors" aren't really "certified" to NFPA 1125 standards nor do they have USDOT EX numbers or paperwork, yet the NAR allows their use by NAR Presidential fiat which allows for the effective overruling of NFPA 1125 in this country. Since when did the NAR get the power to overrrule NFPA regulations in a state for its members? I don't think the NAR was ever given that authority or power by any AHJ.

If one of these motors blows somebodies eye or hand off, whose liability will it be? Jiri Taborski in the Czech Republic? Good luck trying to sue him from here. Or is it more likely the NAR will be sued into oblivion for allowing these motors to be used by its members? You can do the math on that one.

Terry Dean
I'm amazed that someone resurrected a 2 year old thread! :confused:

There are many conflicting rules and regulation, and organizations involved, so certain issues you raise are not necessarily so black and white.

NAR and FAI are not the same. NAR happens to be the designated oversite organization for FAI Spacemodeling in the US, but all FAI competitors are FAI members and launch under FAI rules. These are different than NAR rules and NFPA 1125 motor certifications do not apply to FAI events. Motor certifications for FAI esentially verify the performance of the motor does not exceed the impulse class limit, and that's it.

Putting as side how the motors got here, which may have been perfectly legal, provided they are not placed in commerce within the US, DOT regulations do not apply, and as BP model rocket motors with less than 62.5 grams of propellant are explicitly not regulated by BATFE, they may not come under BATFE requirements either.

As far a legal liability is concerned for any launch, the owner of the rocket bears the legal responsibility for the safe operation of the rocket and motor, not the manufacturer. At an "organized" launch, the RSO would also be legally liable as he (she) is responsible for all matters of safety at the range. The only way a manufacturer could be successfully sued would be if it could be shown that the motors were defective by design from the factory, and not damaged in any way in transportation, storage, handling or use, and that is almost impossible to prove in a court.

I would be surprised if a FAI launch was co-located with a NAR launch, that insurance details were not ironed out before the event by the principals involved. They are not irresponsible people.

Bob
 
The rather recent changes to the Pink Book allow for FAI type events to be held under NAR jurisdiction. That allows FAI contests to be held in the US while still having NAR insurance coverage. That's something I looked into when I organized an FAI contest here in the states.
 
Wow, now you have done it.

Tell us more about motors made in New Zealand! Home-made or commercial.

And when can you ship....


Chas
 
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