DMS CATO: AT's Response

[MartyS]

On March 19, an AT J250 DMS of mine CATOd. After posting about it, I filed a MESS report and notified the vendor and Aerotech. AT responded in less than one day. I thought I would post AT’s entire response here so everyone interested could share their thoughts.

Hi Marty,

Please provide me with a shipping address and a copy of your NAR membership/cert level card and if you have a receipt for the motor e-mail me a copy.

The J250 you purchased had a defective F/G case, the supplier of these cases failed to provide both the proper weave and epoxy filler on a small portion of the cases we received, this defect is undetectable to the naked eye and is only discoverable under heat and pressure.

The case being used with the current production run has been totally redesigned to prevent this from happening, in fact this engineering change has been applied to the entire 54mm line of motors.

There has been a total of four reported failures of the J250 that I know of that used the first iteration casing, the majority of the motors have worked and all functioned nominally during testing and TMT certification.

The customer is the first line of notification of a problem occurring in the field, without timely reporting corrective action is delayed, more aptly stated the customers are the “only ones” reporting issues…..

Let me know what motor you would like for a replacement, the redesigned J250 DMS or a equivalent RMS reload.


Best Regards.

Karl Baumann
Vice President,
R&D and Facilities
RCS RMC, Inc.
Cedar City, Utah

​

I appreciate AT’s quick response to my email and offer to fulfill its obligations under the warranty. I also appreciate AT’s efforts to identify the precise cause of the defect and implement a solution. DMS could be a nice option for many fliers. Lastly, I appreciate ATs high level of candor, though this may have been unintentional.

Please re-read the second and third paragraphs of AT’s response. It’s obvious: when my motor CATOd, AT was already aware of an increased CATO risk. AT knows now and has known for some undisclosed time that the “first iteration” cases are defective. It also appears that this “first iteration” defect isn’t limited to the J250 case; all of the 54mm DMS motor casings have been redesigned, not just the J250. I’m pretty annoyed to learn now, after a CATO, that AT already knew about this problem.

Why hasn’t Aerotech recalled these “first iteration” DMS motors that it knows to be defective? Defective ACHP rocket motors are dangerous. Businesses that knowingly market dangerous products put themselves and everyone else at risk. Short of a recall, at a minimum AT should have notified vendors and fliers of this dangerous defect. When did AT plan on telling us? If AT tells one person in a private email after a CATO, it’s too late and we’re all lucky nobody was hurt.

I am not persuaded by “only four reported J250 CATOs that I know of, the majority have worked.” The number of CATOs (that AT knows of) is meaningless without context establishing that the DMS CATO rate is no greater than that for other motors. For what it’s worth, anecdotal evidence suggests that DMS motors CATO at a far higher rate. Only AT can provide this context, and it has concealed the data.

I understand that CATOs happen. But sometimes, and maybe DMS is one of those times, saying that "CATOs just happen" lets the manufacturer off the hook too easily.

Maybe I shouldn't be annoyed, but I am. What do you think?

 

[Bat-mite]

I would be exceptionally annoyed, and switch to CTI or Loki.

 

[CzTeacherMan]

Great response to a problem that maybe didn't have to happen in the first place. I've never purchased a DMS, nor do I plan to. The whole concept is bound to have these kinds of problems. Think about it... They're trying to make single use motors cheaply. Cheaply being the key word. Any RMS system is going to have built in strength with the motor casing because they're designed to fire many many times, so they're over engineered. A DMS is designed to fire once and only once, so the manufacturer has incentive to do it as cheaply as possible. I'll stick with reloads. Always. And CTI just happens to be my motor of choice, through the 54mm size. AT does the hobbyline far better than CTI, so for little stuff, that's where I go... But I still go reload, not single use.

 

[jimzcatz]

Just remember guys, single use was ALL we had when this whole circus started. I plaud Aerotech, and find no fault with them. Telling someone to switch away from them is just plain assinine.

 

[mpitfield]

At first glance your reaction seems a bit harsh as AT has taken full ownership and was very candid. However, like you said, when you reread it and digest it I am with you, your thoughts seem very rational, fair and in perspective. Personally I like hardware and reloads, it appeals to my hopeless geeky wanna be a engineer/rocket scientist side.

 

[kjkcolorado]

I think you are annoyed for a good reason. History is littered with examples of know problems that are not disclosed until later. Pharmaceuticals, medical equipment, cars, toys, dog food, etc.... the list goes on and on. In many of those cases people are hurt (or worse), and there can be legal action. Sometimes the companies responsible suffer financial consequences (lawsuits or loss of business), occasionally up to the point of going out of business. The examples I listed are all very large markets with a lot of competition.

The challenge in our hobby of rocketry is the small market and limited number of choice. If enough people refuse to support a certain vendor/company or attempt legal action, the results could ultimately be detrimental to our community. Fewer choices and higher costs are a possibility.

I don't point this out to justify what you know about AT's handling of this, but it makes me pause to pile on. I'm 100% CTI for my HPR/MPR motors. That decision was made 3 years ago when I became a BAR and started into reloadables, and only because I viewed it as an easier choice. I had my first CTI failure this February. CTI is replacing my damaged hardware and the reload. What would I do if I found out they previously knew of a problem or high failure fate of that reload? I'd probably piss and moan, then look at my range box of complete sets of CTI 29, 38 and 54mm cases and accessories and go buy more CTI reloads. Not saying that's right, just my reality.

 

[grouch]

I applaud AT for owning it. I am probably in the minority but I have learned long ago that every rocket has an expiration date stamped somewhere on it. It's usually in a place you can't see. That said, it doesn't matter if my favorite bird CATOs, core samples or flies away. All of them will happen and usually there is nobody to blame. Trying to make AT out to be a boogie man because they did not recall a "possible" issue with a percentage of a lot number is a bit harsh. I don't care for that sort of thing. Sure, I'm a bit of an AT fanboy and will continue to be so because they are a good company that tries to bring new stuff to the market. I have flown plenty of other brands too. In fact two of my dead rockets were at the hands of a tardy CTI ejection charge that zippered the crap out of them. I stopped flying them not because of that though, it pry of the game. I stopped flying them because I discovered I like building motors. Switch, don't switch but be careful with trying to blame one of the few motor manufacturers we have. I have seen plenty of DMS motors fly without issue. Again, you seem to be taking this much harder than you should be. It happens to each and everyone of us if you fly enough.

 

[danielsadjadi]

I believe Aerotech should hold greater responsibility to this issue even if it wasn't detectable by eye on quality inspection, ESPECIALLY when receiving multiple complaints about that specific model failing. Aerotech is the only company that distributes their motors to vendors, and it is their job to stop distribution of unsatisfactory product when making changes to the problematic motor. I myself have had a rocket CATO with a single use Aerotech motor, and when contacting Aerotech they refused to compensate the loss of the expensive payload on board the rocket. For all the people kissing AT's ass, I don't care if they made your childhood memories flying your very first rocket, this is a real issue they're neglecting to fix.

 

[MartyS]

I applaud AT for owning it.

Telling one person (me) in a private email is not "owning it" in any sense of the term. "Owning it" would involve, at a minimum, providing notice on the AT website that the "first iteration" motors are known to have a high failure rate. AT, to its credit, has done this with respect to the thrust ring defect. Why not with this issue?

The only reason you know about this problem is because I posted this email, not because AT has publicly acknowledged it.

 

[danielsadjadi]

The only reason you know about this problem is because I posted this email, not because AT has publicly acknowledged it.

Now that's owning it.

 

[mikec]

providing notice on the AT website that the "first iteration" motors are known to have a high failure rate.

They saw 4 failures out of however many they made in the first iteration. One could plausibly assume that there were hundreds of motors, at least, in that batch. Not clear to me that's a high rate.

 

[Nick@JET]

My very first MPR rocket / motor was an Initiator and a G reload... I knew nobody in rocketry and built following instructions. Invited 20 or so friends to a launch and 40' up BANG - motor and rocket destroyed.. My friend leans over and said "that was the coolest 40' I've ever saw"

That was my introduction into anything past an E9. So I call Aerotech and told them I think I put the motor together wrong but want to know what I did. The AT guy said not to worry, sorry about your experience I'll ship you everything today" Free. Coming from race cars where nothing high performance is guaranteed I couldn't believe it.
Certainly glad the warranty motors otherwise a company could but out anything but still shocked this industry warrant a hobby rocket engine. Maybe I'm naive but how can the recall hundreds or thousands of motors that tested fine and a couple people had failures. They took care of me and they took care of you so on my eyes they did the right thing as best they could and still run a business. They want their customers happy and can bet they don't want bad publicity. You might be reading into that response a little too much. I think every rocket motor has a CATO risk


It would make me sick too to lose a rocket (and I've had a couple of Catos) but it's going to happen. Learn from each one and apply that to the next and some are completely out of your hands. Like my wife said to me after my last Cato " did you have fun building it?, then build another one".

I did see someone at the three oaks launch but extra epoxy on a DMS thrust ring. I'm definitely a reload guy as much as possible though now, but I've launch numerous DMS with not one issue. You could probably sell that replacement J250 and apply that to a reload of your choice. I personally saw AT, LOKI and CTI J reloads this weekend and they were all awesome looking, just depends which one you want to try and how much assemble you want to do.

 

[danielsadjadi]

Maybe I'm naive but how can the recall hundreds or thousands of motors that tested fine and a couple people had failures.

AT doesn't make thousands of J250's, they only make to vendors demands, which there isn't much demand compared to other motors for a J250. For even a few complaints, it is something they should take very seriously not only to certification, but peoples safety.

 

[Buckeye]

I believe Aerotech should hold greater responsibility to this issue even if it wasn't detectable by eye on quality inspection, ESPECIALLY when receiving multiple complaints about that specific model failing. Aerotech is the only company that distributes their motors to vendors, and it is their job to stop distribution of unsatisfactory product when making changes to the problematic motor. I myself have had a rocket CATO with a single use Aerotech motor, and when contacting Aerotech they refused to compensate the loss of the expensive payload on board the rocket. For all the people kissing AT's ass, I don't care if they made your childhood memories flying your very first rocket, this is a real issue they're neglecting to fix.

Agreed. Since AT isn't talking, I look to the retailer as the next line of defense to selling a defective, dangerous product to the customer. Other than Apogee, I don't see vendors issuing any specific warnings on the motors they sell.

I have a K535 in my stockpile that now gives me great pause. If I put it up in the Yard Sale with the honorable warning, "Includes faulty thrust ring and defective casing that may destroy your rocket" I wonder what the interest would be. I think I just answered my own question.

 

[H_Rocket]

Personally, when I read comments like above the first thing I think is: who here is willing to pay for the quality and reliability they are demanding?

As to ownership - hell, find me a major manufacturer of anything that will own up to a potential problem with out a legal gun to their head.

 

[Buckeye]

...In fact two of my dead rockets were at the hands of a tardy CTI ejection charge ...

A bonus delay is not quite the same thing as a motor that self-destructs just 2 feet off the pad.

 

[KenRico]

I did the recommended tape on the L1000W and the thrust ring was fine .

Mostly, I prefer Reloads to DMS but ever so often it makes sense to use the Single Use for night launch or am short the hardware - I love the H45 in my Funk Saucer or if locked into Class 1 may fire at H115-DM .

Now the most fun was the EZ RMS H550 and its DMS counter part - have flown repeatedly with no issue and they are HIGH THRUST . Technically the EZ RMS parts were shelved due to an issue but I liked it not having to clean my case closure .

I'm not going to call it quits on a whole product line or mfg because of an issue that the normal checks and balances didn't shake out ..

Kenny

 

[rharshberger]

Personally I don't have reason to doubt Karl Baumann, or Charlie Savoie (I haven't had interactions with other members of AT), if Karl says that 4 motors have failed due to this defect, and probably several hundred (at least have been made) that is a fairly small percentage. You can file a MESS report, but the manufacturers don't receive that information iirc. If Karls say's 4 have been reported, then 4 have been reported. Things get way blown up here as we are a small community, as such there may have been 5 or more members here at the launch where this particular J250 Cato'd, if each of them gets on and says they saw a J250 Cato but no other information like where, when, and to who, then the rest of the TRF just sees five J250 cato's when there was actually just one. That's how these things get blown out of proportion, especially when its only happened FOUR times so far, will there be others, its very likely as there are members of the rocketry community who still have 1st run J250s in their inventories, the best thing we can do is be aware and make sure our local fliers are aware, if the numbers are significant enough (I have no idea what AT considers significant) then AT will put out a PSA with further information.

I have a L1000W DMS I plan on flying in 3 weeks as a pre-cert flight for my L3, yes I am a bit nervous about it, but also am aware of the known faults of the L1000W.

 

[DizWolf]

I'd also be slightly annoyed, But...and this may shock some people.... I get AT's take on this all.

They know there's a defect. OK. But it's only a possible defect. Remember, all the motors survived both testing, and being sent to TMT. 4 failures (three presumably prior to yours) doesn't warrant a recall. An adjustment to future builds? yep. The two things are not always related.

Losing a bird SUCKS....but I don't think AT is leaving time bombs out there.


As for owning it.... they watch these forums. They've contacted me privately after seeing CATO photos to try and find an owner, but they rarely post publicly, and never in a customer service aspect. Trust me, they knew you posted here, and their reply would be copy/pasted right here. So... it's indirectly publicly taking responsibility.

 

[cavecentral]

I don't think the failure rate is high enough to warrant a recall. AT can't swap the case out for you or anything, it is a total loss. With RMS they could do so more easily (ship a new liner or whatever).