Old Motors

I am a BAR for the 2nd time. Started around 1968 and now I'm back after a 20-year hiatus. I found my old flight box and was surprised at the number of motors I had. Are the black powder motors trash at this point? They have been stored in a shed, so have been through many weather cycles.

I also have some Aerotech motors. I believe AP should still be good, but would like to confirm that. To show how long it's been, the G75 reloads had a price tag of $9.99. Good news is, the box had my RMS 24/40 reload and Dr Rocket 29mm reload hardware, and I had cleaned them well prior to storage.

I also have 3 of the Apogee medalist 18mm motors. Wondering if they might still be good as well.

Thanks.

Jeff

Jeff, the black powder motors from that age, unless they have been very carefully stored in ultra-dry, temperature-controlled conditions, are useless. Dispose of them in some environmentally safe fashion.
APCP motors are a complicated question. Even under ideal storage conditions, the shelf-life varies a lot. Any propellant that uses zinc to make thick white smoke will swell over time and develop a thick, crusty white coating on the surface that makes it very difficult to ignite. Aerotech White Lightning, CTI WH, Loki white, and my own home-made versions all have this characteristic. I suspect that this characteristic has something to do with a slow chemical reaction between the propellant components themselves, and is independent of storage conditions.
The AT G75 that is approx 20 years old is a J, or Black Jack formula, and I have no data whatsoever as to how well that stands up over time. I do have some limited experience with a pair of 25 year old AT Blue Thunder motors, and they retained their dimensions well and were quite easy to light. I have kept some of my own aluminum-fueled propellants catalyzed with either iron oxides or copper oxides around under good storage conditions for as long as 8 years, and they lit up and performed just fine.
Also, I have no information on the Apogee medalist motors.

This is an excellent question. I hope other people with experience respond to it.

Alan

Follow the advice of Alan Whitmore he is the current chairperson for Tripoli Motor Testing TRA's motor certifying group, great advice.

I don't think the BP situation is quite as dire as Alan said. If your black powder motors have been reasonably stored, they should work fine as long as you stay away from some known problematic kinds like FSI. I routinely use 30+ year old Estes motors that have been in temperatures generally under 85F and I don't have a seriously abnormal failure rate. It's always fairly warm where I fly now which helps. The NAR (which certifies most of the BP) actually has an old motor test/report program to gather data - there has been discussion about whether there is a need to de-certify very old motors and there is not much good data available. If you are a member they will even grant you a one-shot permission to use motor types whose certification has expired (due to being discontinued) as long as you promise to send in data on success/failure.

On the other hand, I generally toss Aerotech white lightning motors after a few years. Even if you can get an old one to light, they will chuff repeatedly (sometimes to hilarious excess) and not provide full thrust.

Thanks everyone. This leads to the question of how to responsibly dispose of old motors.

Jeff Curtis said:

Thanks everyone. This leads to the question of how to responsibly dispose of old motors.

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Soak BP motors in water or bury in ground nozzle exposed and light, with plenty of additional distance for safety. AP motors can do the same for if single use, reloads burn like road flares when not contained by a case.

caveduck said:

I don't think the BP situation is quite as dire as Alan said. If your black powder motors have been reasonably stored, they should work fine as long as you stay away from some known problematic kinds like FSI. I routinely use 30+ year old Estes motors that have been in temperatures generally under 85F and I don't have a seriously abnormal failure rate. It's always fairly warm where I fly now which helps. The NAR (which certifies most of the BP) actually has an old motor test/report program to gather data - there has been discussion about whether there is a need to de-certify very old motors and there is not much good data available. If you are a member they will even grant you a one-shot permission to use motor types whose certification has expired (due to being discontinued) as long as you promise to send in data on success/failure.

On the other hand, I generally toss Aerotech white lightning motors after a few years. Even if you can get an old one to light, they will chuff repeatedly (sometimes to hilarious excess) and not provide full thrust.

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I'll take 'em...
I've lit E18's from 1999 with no problem.
OP: if all of your old AP motors are still sealed, and don't show evidence of swelling, you should be OK. White Lightning when oxidized gets a white-ish coating on it, which if a reload, can be sanded off where the igniter is positioned and still be lit.
For the black powder motors, bury a few nozzle up and test fire them. Or saucers...

Build a test mule rocket, something simple and low cost that will hold the various size motors you have, and use the motors.

A cato is the worst thing that can happen, no different than any other launch.

caveduck said:

I don't think the BP situation is quite as dire as Alan said. If your black powder motors have been reasonably stored, they should work fine as long as you stay away from some known problematic kinds like FSI. I routinely use 30+ year old Estes motors that have been in temperatures generally under 85F and I don't have a seriously abnormal failure rate. It's always fairly warm where I fly now which helps. The NAR (which certifies most of the BP) actually has an old motor test/report program to gather data - there has been discussion about whether there is a need to de-certify very old motors and there is not much good data available. If you are a member they will even grant you a one-shot permission to use motor types whose certification has expired (due to being discontinued) as long as you promise to send in data on success/failure.

On the other hand, I generally toss Aerotech white lightning motors after a few years. Even if you can get an old one to light, they will chuff repeatedly (sometimes to hilarious excess) and not provide full thrust.

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So, what has been done on the NAR old motor testing program. Which old motors were granted usage permission? Is it truly just a one-shot permission?

The motor certification is generally pulled when a motor is known to no longer be safe, or known to perform significantly outside of its certification specs. Certification is also pulled simply when a manufacturer goes out of business. This is liability issue, since the NAR provides member insurance, and would be at a greater risk if there is no manufacturer to sue. Centuri and Cox are associated with Estes, but I'm not a lawyer, and even current manufacturers often state a liability time limit on their products.

What is the legal status of de-certified motors, particularly for collectors. Do they instantly become fireworks without the model rocket motor exemption? Some states and towns do not allow use or storage of consumer fireworks. Iowa has recently loosened up on its anti-fireworks laws, but now it is rather more seasonal and patchy.

Alan15578 said:

So, what has been done on the NAR old motor testing program. Which old motors were granted usage permission? Is it truly just a one-shot permission?

The motor certification is generally pulled when a motor is known to no longer be safe, or known to perform significantly outside of its certification specs. Certification is also pulled simply when a manufacturer goes out of business. This is liability issue, since the NAR provides member insurance, and would be at a greater risk if there is no manufacturer to sue. Centuri and Cox are associated with Estes, but I'm not a lawyer, and even current manufacturers often state a liability time limit on their products.

What is the legal status of de-certified motors, particularly for collectors. Do they instantly become fireworks without the model rocket motor exemption? Some states and towns do not allow use or storage of consumer fireworks. Iowa has recently loosened up on its anti-fireworks laws, but now it is rather more seasonal and patchy.

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I believe the old motor cert program is still available as we have a flyer who flys motors under that from time to time.

I've recently fired some 2000 ish Estes B and C motors -they worked. I had deliberately had them in a dry place for six months.

If you have many then the best action could be to try one of each, all according to what your club permits

I flew some motors from 1976. They fly fine.

Some must be flown as research motors. Some will not fly at all due to oxidation.

To add some details - NFPA section 4.19.1 requires "certified" motors be used, so in all NFPA states, certified motors are required, and your NAR/TRA insurance only covers use of certified motors.

The NAR Expired Motor Testing Program has been administered by Steve Lubliner for a long time to provide a way to legitimately fly motors that have been decertified for other than safety reasons. Details are here: https://www.nar.org/wp-content/uploads/2014/07/NAR-Expired-Motor-Testing-Program.pdf

The Tripoli research launch FAQ explicitly says you can fly expired commercial motors at EX launches, again as long as they weren't decertified for safety reasons.

jd2cylman said:

I'll take 'em...
I've lit E18's from 1999 with no problem.
OP: if all of your old AP motors are still sealed, and don't show evidence of swelling, you should be OK. White Lightning when oxidized gets a white-ish coating on it, which if a reload, can be sanded off where the igniter is positioned and still be lit.

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If they have been totally sealed then chances are much better. I've been told personally by people who really should know that WL propellant is hygroscopic, removal of surface oxide can get them lit but will not restore Isp if they have taken on moisture. I've had C-slot reload grains where the slot had completely swelled shut. They were smaller ones, not worth the time investment to re-cut the slots and bake them out.

I have flown Vulcan motors from 1988 - 93 & 95, at an EX launch in Camden with no problems at all.
They have been stored in a cool, dry place.

I have flown Centuri B4 minis from 1973 under the NAR expired motor program. No problems. Program permission is for specific launches, but I list all the club launches for the year when I make my request.

I will note two things to consider for old black powder motors that have come up in other threads. Look at the nozzles - there are certain batches/age ranges that had poor clay and have crumbled.
Fly them in moderate weather - not in winter. BP motors that have seen large thermal cycles don’t like the cold.

(And the saucer recommendation is a good one. )

lakeroadster said:

Build a test mule rocket, something simple and low cost that will hold the various size motors you have, and use the motors.

A cato is the worst thing that can happen, no different than any other launch.

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Besides a cato, various risks associated with under performance and delay accuracy must also be considered. I once coaxed an old crusty E18 to light. After a significant period of chuffing, the rocket reached maybe 120ft in height. The parachute got deployed after apogee and inflated right above the ground, just in time to prevent damage. It was certainly an entertaining flight, but not exactly what was planned.

Reinhard

When I got back in the hobby a few months back I found a guy selling Estes A8-3 educator packs from around 1989/1990. I bought everything he had for a very reasonable price.

We have flown over a hundred of them without a single incident.

I found a pack of old B6-4 Centuri motors (White/blue and orange box) from god knows when... Box was trashed but the motor looked ok. Flew all three without incident. Don't know where they came from or how they were stored. I took a break from the hobby but in the 20ish years I flew i have had only a handful of issues with motors and none of them were due to age.

Is there a list of motors that have been decertified for safety reasons? Would somebody post one?

Alan15578 said:

Is there a list of motors that have been decertified for safety reasons? Would somebody post one?

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The Ellis Mountain J228 is the only one I can remember that earned itself an outright decertification for safety.

Estes E15 would also join that list.

The AT G8, although you could argue that it was decertified for a technical violation, that may or may not be for safety.
The 20 N-s AVI D6.1, was down graded to 15 N-s, because of frequent casing burn through, probably a voluntary action before an official safety decertification.
I think Estes had a voluntary safety recall of the November 1970 D13, but they soon replaced and rebadged it as the D12,perhaps acting just ahead of formal decertification.
FSI had some motors that had substandard reliability, but were actually threatened with decertification over labeling issues.

I decided to try the old Estes engines as most were in unopen packs. I have not had a single issue.