AeroTech G35 Problems

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Well-Known Member
May 25, 2002
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From the AT website:

G35W Econojet Consumer Notification
AeroTech has identified a higher-than-normal failure rate on certain batches of G35W Econojet motors. The lot codes affected are:

Customers with motors displaying these lot codes are requested not to use them, and to contact AeroTech for disposition and replacement instructions. AeroTech apologizes for any inconvenience this has caused its customers, and will honor all G35W failure claims in accordance with our Warranty Policy.
Anybody know how Aerotech is handling this? I've got 10 of these motors purchased from various mail order dealers, and potential major, major hassles if I try to replace them through the dealer. Not to mentioned the hit and miss availability.


"Customers with motors displaying these lot codes are requested not to use them, and to contact AeroTech for disposition and replacement instructions."
Whaddya know. I have a catoed 001914 motor right here. I was gonna use the other one, thanks for the heads up.
I contacted Aerotech Customer Service this morning and talked with Diane and got these details.

Aerotech will exchange the faulty G35s for either new G35 Econojets or F20 Econojets. The problem is that the G35 is being redesigned and is not currently available, but should be in several weeks. (When pressed, Diane said they were hoping for about 8 weeks or less, but admitted that she was not certain). However, I could have the F20s now.

Rather than have me mail the motors (nearly impossible due to Hazmat issues), Aerotech asked me to remove the paper cap at the delay end of the motor (which is stamped with the lot number and delay) and mail them to Aerotech as proof of purchase. Sounds pretty simple and I thought it was a good way of handling the recall.

While I'm a bit concerned about waiting (and wondering) when the replacement motors might arrive, I'd rather have the G35s than the lower powered F20s, so I'm going to pursue that route. (I still have a few good G35s in my flight box.) Maybe Joe Berger or someone else at Aerotech might keep us posted periodically as to the status of the G35s and when the new designs will be shipped.

NAR #83277
Tripoli Pittsburgh
Pittsburgh Space Command
Ok...does any one know what the exact failure is? Are we talkin' CATO's here? I have a 2-pack of 001914 that are supposed to boost my MAXI-Gyroc this weekend at Whitakers. I'm glad I came back and checked this thread.
Eugene - oh go ahead and try those motors!! and be sure to take pictures of it, you will definitely be king of the "Best Of TRF Photos" thread!!!

smiles! (It's definitely CATOs.)
Yep, I think the 1914s are CATOers.

Oh yea, and when it does cato from what I have seen, it's not very spectacular. Just a little puff of smoke and a pop.
Maybe that explains all the problems that I've been having. I don't remember what the serial numbers were though.

I however don't plan on using any more of them until Aerotech has redesigned the case which I hear thats what they're doing right now.

It's just odd that I haven't had a problem with any other AT single use motor including several G80's.
Blue Ninja

You're absolutely right, it's not spectacular at all. All mine did the same thing. The pop you hear is the motor blowing the nozzle out. When you look at the propellant grain afterwards, you usually don't see any burned spots. The problem however is that when these motors CATO, they fragment into small, sharp pieces that literally tears the livin' crap out of the motor mount tube.
OK, my turn - I got one (G35-7) that looks like a misfire. the nozzle is blown away, the bottom of the motor where the tape ring was is gone. the delay grain looks to be untouched and the paper cap is there with powder under it. I will post a pic later. serial # 003180, which isn't on the recall lists... anyways it doesn't look like the description of any of these CATOs.
nice looking job they did!

the forward closure is a threaded plastic fitting and the ejection charge is not the full-diameter charge they used to have. they also say the casings won't get quite so hot since they added an insulator.

i will be testing them today
Did you have them shipped or did you buy them from the store?

Cool, does the threaded part screw off? I've seen the F20s and G80s, i guess this is their universal motor design (or at least is for problematic motors)
here's a picture of the CATOed G35. as you can see the rear end including the nozzle is completely blown out. (bear with me, I've never had a CATO before - great fun!)
Has anyone gotten their replacement G35's yet? I sent in 4 stickers and havent heard anything yet.
Elapid, are those new motors replacements?
when do ther new motors comes out?? we have had a set of the recalled for over 3 months and havent heard anything from aerotech. we had one cato on us and it broke up into about 6 pieces but it didnt tear the crap outta the motor mount... hmm:confused:
Yea.... I notified them in April and nothing yet... There was some correspondence within the next few days.
FWIW, I want to pass along a a bit of information here about AT's warrantee replacement of G35 CATOS...

First, there is a special form (can't remember the name of it right now) that AT has to apply for with USPS in order to ship your replacement motors. It takes up to 30 days to receive that form & then they are shipped by ground carrier only, which again takes longer than sending a standard package (especially going from Utah to me here in FL). It took about 45 days (but maybe as long as 2 months) IIRC from the time that I sent my information to AT to when I received my replacement motors. Your mileage may vary. The hold up ultimately is not with AT but with USPS. Patience. You will be taken care of & rewarded for your wait!

Secondly, I was somewhat pleasantly surprised to receive a 2-pack of F20-4W motors to replace the one G35-4W CATO. Others may find it a mixed bag since they lost a G35 & would like another G35. Look at the bright side (& don't be upset) will/should get TWO motors :D

Hang in there! HTH,
Did they ask you what kind of motors you wanted? I was asked that, and said that I wanted G35s. Maybe thats why they are slow also, because they are designing the case.

I called Aerotech's Customer Service office today and talked with Craig and got the following information:

The G35 is still in the process of being redesigned, so it is not yet in production and Craig was not able to give me a timeframe.

When I originally sent Aerotech the caps for the recalled motors, I asked if they would substitute an equal value of G40 SU motors instead of the G35 Econojets. At the time (late April), they told me that they would be glad to do it, but they did not have any G40s in production at the moment. Today Craig told me that they had received a batch of SU phenolic casings from their supplier, but they were defective. (Craig implied that they had a number of problems with SU cases recently-- and I've been noting that virtually no SU motors are available from any of the major hobby shops.) Aerotech thinks that the problem has been resolved and new casings should arrive in a "week or two", although again, he was not certain about the time-frame.

So it looks as if it will be at least several more weeks before any Econojet replacements or SU motors are available.

A quick comment about lalligood's comment on the USPS shipping process. It is true that Aerotech (or anyone shipping motors) needs a letter of authorization from the USPS's DC headquarters in order to ship motors. But the letter is a blanket authorization for shipping certain classes of motors and is not tied to the shipment of a particular customer's order. (See section 341.22 of USPS Publication 52 for the details). As a major manufacturer of motors I would think that Aerotech should/would have this authorization as a matter of course. If Aerotech was using the lack of this authorization as an excuse for shipping delays, I would be concerned and/or miffed.

Bottom line, the motors won't be here by LDRS, and NARAM is looking pretty iffy.

NAR 83277
Pittsburgh Space Command
Tripoli Pittsburgh

After hearing a rumour at yesterday's Pittsburgh Space Command launch that the G35 and G40's were being shipped, I called Aerotech this morning and found out that they are still on hold. The G35 is being "re-engineered" with a molded case similar to the F20, and the G40 is on hold mainly because of problems with the SU cases that Aerotech gets from their suppliers.

Aerotech continues to hope that the G40 will be back in production in "a week or so", but they've said that the last couple of times I've called. They are not giving any estimates on the G35. I can't help but note that it has now been over three months since the recall first went out, with resolution still on hold.

NAR #83277
Pittsburgh Space Command
Tripoli Pittsburgh
Hey there G35 fans!

We did in fact come across a very high failure rate on the G35's. After review and further examination of the cases returned to us, we did determine that it was the casing material itself. Our vendor had relocated and had difficulties with their new staff and material supplier.

We had to put all single use motor production on hold as we started sorting out the problems.

After the failure rate on the G35's was beyond acceptable levels, we decided to put those particular motors on permanent hold until a molded case could be designed and tested.

Great News! The mold has been completed and samples are being run this week. They should be sent to us as early as next week so that we may begin the testing phase on this new casing. We are extremely excited about this new case. We should be able to guarantee a much higher success rate with this new design.

We are also going to utilze this case for the G38 B/J econojets as well.

ALL G35 warranties will be honored as soon as we prove this new casing's reliability. We have strong confidence that it will be a revolutionary solution!!

So hang in there a little longer G35 fans. We are almost there!

As far as the other motor production goes, we did receive a sample of some new material from the vendor and it appears that they figured out their problems. We especially focused on the G40's and the testing phase of this sample batch did pass our criteria. Now we are just awaiting on a production run quantity so that we can start pumping the single use favorites out once again.
Joe, thank you very much for the update. I still have a pack of the recalled G35s and am patiently awaiting the new ones to arrive for replacement. I think we are all anxiously awaiting the G38s to come back out again! Very nice. Thank you Sir.
Originally posted by firemanup
I have a pack of G35's with no lot number listed on them...???

Now what................... :mad:

The lot numbers are usually on the paper cap over the ejection charge.

Go to the aerotech site: about 1/2 way down the home page you find this:

"G35W Econojet Consumer Notification
AeroTech has identified a higher-than-normal failure rate on certain batches of G35W Econojet motors. The lot codes affected are:


Customers with motors displaying these lot codes are requested not to use them, and to contact AeroTech for disposition and replacement instructions. AeroTech apologizes for any inconvenience this has caused its customers, and will honor all G35W failure claims in accordance with our Warranty Policy."

Send them an email with the details to: [email protected]
Yes sir I know that's where they usually are.. but all the paper cap says is

AeroTech G35-7W.. and the little white spot/rectangle on the paper label on the motor is blank also...???????????????

I bought them a couple weeks ago from a vendor at a launch, how long he'd had them before that I have no idea.. i can find no production date on them either..
If there is no lot number on the motors then it was fabricated in Texas by Ellis Mountain. There should be no problems with these.