Launching old engines?

[tagerton]

I have a number of old engines many of which are ~10 years old. They were stored in doors for many years, but were in a hot and humid garage for about 3 years. They include a few D and E estes engines. A 24mm Rocket Vision F72 and E(something) engine. As well as a 29mm G80 Aerotech engine. I'm concerned about putting these in my new rockets for fear of a CATO. Is there a typical lifespan on engines and are my concerns warranted?

Many years ago, I did launch an F engine that was given me to be a cousin that was at least 10 years old at the time, the engine worked, but the rocket shredded. (It was a cheap estes rocket that was never meant to go that fast).

Thanks,
-Ted

[rockets4kids]

For black power motors (Estes) the real problem is hot/cold cycling which can cause the propellant grain to crack. I'm not sure about the shelf life of AP (if that is what your larger motors are.)

My suggestion if you want to fly them is to fly them in something you don't mind losing.

[cwbullet]

I suspect you might be able launch them on research days, but I will defer to a more expert answer.

[chadrog]

If any of the motors are no longer certified, and you want to go by the book, this is the NAR protocol: http://www.nar.org/pdf/Expired%20Mot...Procedures.pdf

[cwbullet]

What about tripoli?

[chadrog]

What about tripoli?

I couldn't say.

[shreadvector]

NO. It does not cause the propellant grain to crack. Temperature cycling results in a loss of the mechanical bond between the propellant grain and the cardbaord casing. This allows the flame to propagate up the sides. There can be a crack between the nozzle and propellant face from temperature cycling, but this results in lower pressure and lower peak thrust UNLESS this also allows the flame to instantly reach the disbonded propellant/casing interface.

For black power motors (Estes) the real problem is hot/cold cycling which can cause the propellant grain to crack. I'm not sure about the shelf life of AP (if that is what your larger motors are.)

My suggestion if you want to fly them is to fly them in something you don't mind losing.

[llickteig1]

I have a number of old engines many of which are ~10 years old. They were stored in doors for many years, but were in a hot and humid garage for about 3 years. They include a few D and E estes engines. A 24mm Rocket Vision F72 and E(something) engine. As well as a 29mm G80 Aerotech engine. I'm concerned about putting these in my new rockets for fear of a CATO. Is there a typical lifespan on engines and are my concerns warranted?

Many years ago, I did launch an F engine that was given me to be a cousin that was at least 10 years old at the time, the engine worked, but the rocket shredded. (It was a cheap estes rocket that was never meant to go that fast).

Thanks,
-Ted

I would not use the Estes motors in a rocket that were stored as described. They will likely go boom for the reason shreadvector mentioned.

The Rocket Vision motors are no longer certified but can be flown at a TRA research launch. I had several of those motors and the delay grains on them behaved badly - way, way, way too long. If they were in my box, I would only fly them in a altimeter deployment rocket.

The G80 should be fine.

Older composite motors (RocketVision and Aerotech) can be a frustrating bugger to ignite due to oxidation on the grains. It may take more than 1 try.

--Lance.

[cwbullet]

I have several old Ellis MTN motors that I ply at our search launches. I think they are in a 3 yr burn period. They are great for minimum diameter and saucers. I glad to hear confirmation that I will be able burn them when I get back. My 12month hiatus will end after the burn period.

[luke strawwalker]

I'd fly them... I've been flying my old stash of 20 year old motors that were stored in an un-air conditioned farmhouse at my Grandmothers in Texas that also got down around freezing when we were out of town in winter, and regularly hit 100 degrees inside in the summer (especially when that stuff was sitting upstairs!) No issues so far...
BUT you *might* want to fly them in an older rocket that if something goes wrong, you're not TOO heartbroken about...

The AP motors should be okay if you can get them lit... depends a lot on the propellant formulation and whether they were "sealed off" from air exposure (in a bag) or "left open" to the air rolling around in an old motor box or something.

Remember that the certs might not be current, so be aware of that... seems silly I know but those ARE the rules and if you're flying under NAR regulations and insurance, if the certs are not in effect and you fly them and something happens, it's uninsured... so launch them at your own risk... (preferably someplace far removed from everything, not at a club launch...)

Later! OL JR

[tagerton]

I'd fly them... I've been flying my old stash of 20 year old motors that were stored in an un-air conditioned farmhouse at my Grandmothers in Texas that also got down around freezing when we were out of town in winter, and regularly hit 100 degrees inside in the summer (especially when that stuff was sitting upstairs!) No issues so far...
BUT you *might* want to fly them in an older rocket that if something goes wrong, you're not TOO heartbroken about...

The AP motors should be okay if you can get them lit... depends a lot on the propellant formulation and whether they were "sealed off" from air exposure (in a bag) or "left open" to the air rolling around in an old motor box or something.

Remember that the certs might not be current, so be aware of that... seems silly I know but those ARE the rules and if you're flying under NAR regulations and insurance, if the certs are not in effect and you fly them and something happens, it's uninsured... so launch them at your own risk... (preferably someplace far removed from everything, not at a club launch...)

Later! OL JR

Ok. It looks like the Rocket Vision motors are no longer certified. That's too bad. It sounds like the G80 should be good though. I'm not sure if I trust it in my new rocket though. I think it's worth it to use new motors. I may be able to grab an older rocket to use it in. I'll have to find something interesting to do with the BP motors.

[cwbullet]

Or launch them at a Tripoli research launch - after joining tripoli.

[BEAR]

Ok, you guys have been talking about more recently manufactured motors, but what about Estes and Flight Systems motors that are 40 years old, and made it from Houston to non-climate controlled buildings here in northern Colorado. I have maybe 50 Estes A's, B's, and C's, and a number of FSI D's, E's, and a few F-100's. I also have a couple of the old Centuri Enerjets. Should I just put them in a display case or do you think they would be safe to fly on a research day?

[luke strawwalker]

Ok, you guys have been talking about more recently manufactured motors, but what about Estes and Flight Systems motors that are 40 years old, and made it from Houston to non-climate controlled buildings here in northern Colorado. I have maybe 50 Estes A's, B's, and C's, and a number of FSI D's, E's, and a few F-100's. I also have a couple of the old Centuri Enerjets. Should I just put them in a display case or do you think they would be safe to fly on a research day?

Cooked in storage in Houston and then frozen sub-zero in storage in N. CO... I dunno, doesn't sound very promising... maybe risky... but hey you never know til you try...

Just don't put them in your prize rocket...

Later! OL JR

[rockets4kids]

There *are* people who collect these old (unfired) motors, so you might want to try to unload them that way. Of course, you are trading one problem for another, because it is as difficult to ship them legally as it is to fire them.

Personally, my suggestion is to just make some saucers from corrugated cardboard. Takes less than an hour even if you have never built one before. And if a motor CATOs, the most you have lost is an hour of your time. Needless to say, you'll want to warn your RSO/LCO and use one of the racks a little further back.

[BEAR]

Thanks for the advice, rockets4kids. You are quite correct, I think, under normal circumstances. Although shipping the motors by ground, should not be an issue since I am an approved Dangerous Goods Shipper and a known shipper for both FedEx and UPS. And since UPS only ships DG by ground, everything should be fine. Anybody want to by some old motors? ( I used to ship explosives, magnetic devices, cans of spray paint, toxins, and other outrageous dangerous goods all over the world, so these are mild compared to shipping a winter survival kit for helicopters that do many over water flights to Greenland. Li-on batteries, flare guns, butane lighters, etc. can seriously get frowned upon.) Now getting State Department licensing for exporting/importing weapons of war and making sure I stayed within ITAR regs. and making sure it was not going to a country or group who had Treasury sanctions against them was a bit more complicated, but quite doable. Shipping fees will be expensive though because they are dangerous goods.

[cwbullet]

Ok, you guys have been talking about more recently manufactured motors, but what about Estes and Flight Systems motors that are 40 years old, and made it from Houston to non-climate controlled buildings here in northern Colorado. I have maybe 50 Estes A's, B's, and C's, and a number of FSI D's, E's, and a few F-100's. I also have a couple of the old Centuri Enerjets. Should I just put them in a display case or do you think they would be safe to fly on a research day?

I would fly em.

[k-rad du0d]

I recently used a bunch of ~18 year old Estes BP engines without issue. They were kept inside in a bedroom closet for their entire lifespan. I would guess that keeping them in a humid/non-temp controlled environment would reduce their viability, but I don't know. I was actually pretty shocked as to how well the ones I used performed after almost 2 decades. Thus, I wouldn't hesitate to give them a shot.

edit: I'm only talking about the BP Estes motors. I have no comment on the composites.

[JStarStar]

I have a huge stash of 30-35+ year-old Estes BP motors (75 or so diamond packs) and I have been launching them at park and picnic launches with no incident. I bought them super cheap a few years ago without any real information on how they had been stored, other than it was a dusty old store (I would guess they did not undergo wild thermal cycling although I doubt they were kept in a 'climate controlled environment').

I've launched probably 20-30 of them with no obvious CATOs that I recall. Most are motor types still in production (but some are not, i.e. B14's). Unless motors have undergone dramatic heat cycling or really violent handling, my bet is they are probably fine.

I probably wouldn't launch any real showcase rockets on decades-old motors, but I don't really have many "showcase rockets" in my fleet.

[tagerton]

So I tried to launch an old aerotech E-15-4. After three failed attempts we could not get it to light. The problem may have been the igniter couldn't get all the way down the fuel grain because it was clogged for some reason. Will try again soon.

[billspad]

So I tried to launch an old aerotech E-15-4. After three failed attempts we could not get it to light. The problem may have been the igniter couldn't get all the way down the fuel grain because it was clogged for some reason. Will try again soon.

The propellant in White Lightning motors swells when they get old. I believe the humidity does it. It's tough on an E15 but you may be able to open up the slot with a small drill bit (by hand!) or a needle file.

[TaekwondoRocketMan]

I have a huge stash of 30-35+ year-old Estes BP motors (75 or so diamond packs) and I have been launching them at park and picnic launches with no incident. I bought them super cheap a few years ago without any real information on how they had been stored, other than it was a dusty old store (I would guess they did not undergo wild thermal cycling although I doubt they were kept in a 'climate controlled environment').

I've launched probably 20-30 of them with no obvious CATOs that I recall. Most are motor types still in production (but some are not, i.e. B14's). Unless motors have undergone dramatic heat cycling or really violent handling, my bet is they are probably fine.

I probably wouldn't launch any real showcase rockets on decades-old motors, but I don't really have many "showcase rockets" in my fleet.

I have used quite a few vintage motors and I've almost never had any problems with them. I use Estes C5-3's all the time without incident and I'm always scouring the internet looking for more. I just fired a 1975 vintage Centuri 1/2A4-3M and it worked perfectly. I did have a 1986 vintage FSI E60-8 that catoed rather spectacularly back in '98 though!

[RocketRob]

I launched a 10 year old econojet G34 and after a few quick sputters the rocket took to the sky and at apogee the chute never deployed and lawn darted somewhere in the field! after talking to a few other people we determined that the BP in the ejection charge had failed, maybe to the BP going bad because of age.

[luke strawwalker]

Also, the larger the motor diameter, for BP motors, the worse the effects of temperature cycling are on the motor and the more likely it is to have a casing delamination. If a motor is dropped when cold, the propellant can crack, but usually the problem with old motors that go boom is due to casing/propellant delamination (seperation). So, basically, the larger the diameter, the more "risky" the motor is to fly if it's been stored in bad conditions...

later! OL JR

[cavecentral]

Also, the larger the motor diameter, for BP motors, the worse the effects of temperature cycling are on the motor and the more likely it is to have a casing delamination. If a motor is dropped when cold, the propellant can crack, but usually the problem with old motors that go boom is due to casing/propellant delamination (seperation). So, basically, the larger the diameter, the more "risky" the motor is to fly if it's been stored in bad conditions...

later! OL JR

Dropping BP and Swelling of the grains such that an igitor cannot fit in an AP mottor are the biggest issues. I also would not trust the delay and certainly change out the ejection charge on the AP. Fly in expendable rockets or an altimeter. I always heard F100s are CATO prone (even when new), but not sure I seen one fail (don't remember).

[neond7]

I found a small cache of Aerotech "F" impulse Econojet motors that I had stored in a closet for 15+ years. All the ones that were sealed in the blister packs lit on the first try and worked great.

The three motors that were loose in the box had a few issues. It took a few copperheads to get two of them to light, I gave up on the third motor after I ran out of ingniters.

[jimzcatz]

the old estes motors would not require a research launch right??

[dpower]

the old estes motors would not require a research launch right??

Nope, just get permission from the NAR, using the expired motor program

[goldlizard]

Two weeks ago I launched off three unopened packs of Estes 1/2A3-2T's, that were 18 years old. No problems, they were bought from Goodwill without knowing their prior history. l know that BP gets stronger with age. Like old dynamite, the nitro glycerin leaches out of the powder with heat and time. That is why they say not to play with or move old explosives. Also the larger the casing the greater chance of this happening. I am also a BP shooter, and that is one of the first things you learn from clubs that shoot is never store BP for more than a year. The best way to dispose of BP is with water, DO NOT BURN IT!!
Happy Flying

[cavecentral]

Two weeks ago I launched off three unopened packs of Estes 1/2A3-2T's, that were 18 years old. No problems, they were bought from Goodwill without knowing their prior history. l know that BP gets stronger with age. Like old dynamite, the nitro glycerin leeches out of the powder with heat and time. That is why they not to play with or move old explosives. Also the larger the casing the greater chance of this happening. I am also a BP shooter, and that is one of the first you learn from clubs that shoot is never store BP for more than a year. The best way to dispose of BP is with water, DO NOT BURN IT!!
Happy Flying

Wow. Never heard this, but something to watch for. I know from a kid old paper fuses on firecrackers were fast and you had to be more careful. I will say that I have BP that is probably 20 years old. Need to test fire when I switch to newer stuff - might not have the same kick.