BP model rocket motor questions

NFPA 1125 states:

Chapter 8 Testing and Certification

8.1 Certification of Model Rocket Motors, Motor-Reloading

Kits, and Components.

8.1.1 A prerequisite for certification of a model rocket motor or motor-reloading kit shall be its prior classification by the

U.S. Department of Transportation (DOT), or competent authority, as a Division 1.3 or 1.4 explosive, or a written acknowledgment

from DOT, or one of its approved testing agencies, that the model rocket motor or motor-reloading kit is a flammable

solid.

So my question is this: are all current BP motors made by Estes and Quest the same in terms of propellant formulation? If not, then can I assume that the estes and quest BP motors have diffrent formulations and therefore different EX numbers..... Is BP is BP...? do the Estes/Quest BP motors essentially use the same BP... Imena if the estes BP formulation is x amount BP, x amount of sulfur, x amoutn of dextrin and you alter those percentages is it considered a new and different propellant formulation, thereby requiring new testing and its own EX number...

What if a new manufacturer came forward and used the same estes or Quest propellant formulation, would they have to go through the entire DOT classification scheme?

Another key factor in BP model rocket construction is the pressure that you press the BP at..... in other words, the Bp has to be pressed at a known pressure for x amount of time to get a uniform density...... would the pressing pressure and resulting density require a different EX number?

anybody know.....? just wondering cuz I don't know..

shockie B)

Reply to
shockwaveriderz
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Technically, yes.

Yes.

No.

Reply to
Dave Grayvis

Too bad DOT doesn't do that so one cannot comply.

The only way you can get ISSUED FS by DOT these days is under EXEMPTION

7887 or if a long series of unlikely events occur.

They have article EX numbers not substance EX numbers.

Yes.

Reply to
Jerry Irvine

My question. Why do you care ?

Reply to
AlMax

SNIP

Try asking them.. ;-)

You can't piggy back on someone else's EX numbers. EX numbers are issued to a manufacturer, not in blanket form for a product type. Each new manufacturer, even if they make something that looks the same and contains the same as something else, is making a "new explosive". You have to go through the same hoops as everyone else. The height and cost of those hoops depends on your history with prior product approvals, but for a brand new manufacturer and product, you can bet some testing will be needed. If not, I'd be totally amazed.

Than what, is the question. A prior product you already make that is approved? If it is a different product as a result of the ballistic differences and whatever else, then you have to get it approvedt. You'd also be challenging the certification staus with the industry. Estes doesn't have an EX number for black powder. Estes has EX numbers for the products they make, each of which contains BP and other materials and is of a specific design. Change the design and it is a different product and has to be submitted for approval. So using your query above, if they developed a new product that was a new product in whole or in part due to BP pressing parameters, well then that is no different than other design changes that make it a new product - it's simply a new product.

If you mean that if you make a motor that looks exactly the same as an Estes C6 and has exactly the same materials and dimensions, does it have to be tested and approved anyways, the answer is: yes. You are not Estes and it is not an Estes C6. You have to convince DOT your product is safe for transport yourself, and get your own approval. Think about it - the first guy to develop a model rocket motor fueled by sodium nitrate and chile powder and that uses a casing made from recycled Mad magazines bonded with squished cockroaches goes through the hassle and expense of getting it approved. Is it then right that everyone else can jump on the bandwagon for free? No, but that is the ethical answer not the technical one. The key issue is, DOT cannot simply rest in peace trusting that every other manufacturer really is making it the same way. Each manufacturer is required to approve their products by themselves. An EX number from DOT says, in writing, "we have reviewed and/or tested this product, and hereby decree that it is suitable for transport in the US, with UN class XXXX and UN shipping name YYYY, and under these packaging conditions." They won't stick their necks out and endorse another company's products carte blanche due to similarity to something else.

Within a manufacturer, new products can sometimes be approved by their similarity to products that company alredy makes that have already been tested and approved. That's a decision DOT makes and it depends on your history with them.

Well, if you're looking to get into the BP motor market, knock yourself out. Manufacturer's license, 1.1D magazines, explosion proof manufacturing facility, thousands of dollars of manufacturing and test equipment, extensive product R&D, testing and DOT approvals, registered packaging, the list goes on. It can be done, but all I'm saying is don't fool yourself into thinking it is anything but a serious investment. If that's where you're headed with the questions that is.. it seems an idea is brewing in your mind...?

Reply to
Mike Dennett

thanks Mike, very informative.... shockie B)

Reply to
shockwaveriderz

Nice post Mike. Very good information.

I'll ask this since you just might know being your position an all.

No beating about the bush.

A company in Europe sells nice little motors that would make nice competition motors for NAR I saw last year.

DHL can ship them by boat when I called them about it. In fact the Space Champion types shipped some in DHL air a few(?) years ago for a few grand in costs.

these have a UN number for Europe. So if I were to import them into the US, would DOT accept their UN number ?

Anyway, when I ran the numbers, the cost of the engines would have to sell for like $5 or $6 each to make only hobby fun money much less a real business margin.

So I gave up looking into it further.

Reply to
AlMax

At a Naram a number of years ago Bill Stine stated that Quest used the same black powder as Estes - BUT - that was back when Quest made their own motors. They have been buying motors from Germany for several years now, much more smoke than Estes and diferent thrust profiles, I'll bet it is a different BP formula. The term 'black powder' is very generic anyhow, even the same manufacturer has multiple fomulaes (not just granulation sizes)

Dale Greene

Reply to
Dale Greene

Makes me wonder about the state of the hobby in Germany and adjacent countries. Any ideas about how many flyers there are in that region, what they fly, their limits, etc.?

Randy

Reply to
<randyolb

USA is 90% of the market.

Sad, eh?

Jerry

Reply to
Jerry Irvine

Why is that sad?

Reply to
Dave Grayvis

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shockie B)

Reply to
shockwaveriderz

Becauase you, an undeserving person, is enjoying the benefit while other far more deserving folks go unserved.

Reply to
Jerry Irvine

From what I know, its a real mixed bag...the UK is somewhere in the middle, Germany is somewhat more strict, Switzerland is pretty open (they have AT motors) and other places (Netherlands) allow EX-type activities. I think the group is called NERO, there's also an awesome video from the 'Danish Space Challenge' who seem to be busy launching lots of rockets and doing test firings on liquid/hybrid motors.

On TRF there is a thread about German rocketry - they have a bunch of Estes-sizes motors, including some very slow-burning motors. They also have something called a 'BC360' (I think), which is a reloadable HPR system.

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- is a good website to look at for Swiss activities.

The general opinion seemed to be that rocketry is very low-key in France, I've never read much about it.

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- a Dutch group who are pretty serious.

Tripoli NL are quite active too, they often come over to UKRA events, and at least 2 (possibly 3+) have certified Level 3 at Pete's.

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- Norwegian group who have developed a 100,000 Ns AP booster

There may well be more groups, but these sites have links to other sites, so should be a start.

HTH,

Of course I can't help but mention M.A.R.S. -

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- who many of you may have heard of since they have launched a few times in the US and various members (most recently Cath and Marcus) have been over to the US to fly - Cath certified L3 at BALLS this year in fact.

Reply to
Niall Oswald

Interesting. It sounds like they need a "GAR" ; )

Randy

Reply to
<randyolb

Thanks Niall. I'm always interested to hear about how things are going in countries outside the U.S.

Randy

Reply to
<randyolb

Yup - you think 62.5g is bad, their limit is 20g! I am reading the site through babelfish, but the gist is there. To fly more than 20g motors, or anything (even A-A) with more than 1 stage you need to complete some kind of course and examination, at some cost. The site bemoans the regulations too - seems like its the same everywhere!

I think this is why the Euro 'big one' is held in Switzerland. The latest issue of the UKRA magazine has a launch report from ALRS V, by Andy Moore, who must be about the only UK flier to have flown an AT Redline motor.

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If you haven't seen the Ariane launch from ALRS V, its worth taking a look at
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Reply to
Niall Oswald

explain.

Reply to
Dave Grayvis

The answer is a qualified "yes". You must still apply for DOT approval. Each nation issues a dicrete approval. When a product carries UN approval in one nation, basically what you do is submit a copy of the approval and whatever went with the application that resulted in that original approval (data, drawings, etc.) to DOT. If there was UN testing that went with the original application, then you'd be submitting the official test report along with the other data. If they accept it, they will issue you a Competent Authority Approval, upon which appears the EX number. Though it is typical for UN nations to accept the classification from other countries, they each have discretionary power and can deny a classification altogether or the UN class on the existing approval if they have reasons of their own to do so - what I mean by this is perhaps they do not agree with another nation's 1.4C classification, so they may come back for example with a choice of taking a

1.3C classification with the data you provided, or you have UN tests run domestically to convince them to honor the 1.4C classificaiton. There's rarely a conflict, but it happens and we've seen it. For example, DOT has a self-imposed 1.4kg inner package propellant weight limit for 1.4C shipping. Canada does not. So up here we can ship Smoky Sam 98mm reloads as 1.4C. In the US the 1.7kg propellant weight per grain limits them to 1.3C, so you won't see them down there - the shipping is too expensive to justify their existence.

In addition to this, you then have to deal with UN registered outer packaging - if you downpack the motors you mention, you are now a packaging manufacturer by definition and will need to make sure whatever you use is UN registered for those products. Every new box size we come up with for example requires drop tests and is then registered with Transport Canada. Luckily that costs us nothing and is a quick process, but it has to be done. I know the Canuck laws inside and out, and they are quite similar if not "remarkably similiar". However, you'd best consult a packaging specialist at DOT I guess to double check and broaden your understanding of this. At Transport Canada they are called "packaging specilalists" but that might not be the terminology there. You'd have to dig around to find out.

Yes, the hard cost of these ventures sucks doesn't it? ;-) As Bruce Hornsby says; "that's just the way it is".

Funnily, there are other companies doing exactly what you mentioned you'd like to do, so maybe you don't have to go all the trouble after all. No, not us, and I won't say who. But hold to hope.

Cheers,

Mike D.

Reply to
Mike Dennett

Thanks Mike. You confirmed my fears,

I hope the others do it however ;-)

Reply to
AlMax

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