AT SU and LMS problems...

[roadkill]

During our THOR Dec.2006 launch I had my spanky new
rocket, 'Pinknose Craypuppy' come down ballistic due to too weak
of an ejection charge on AT SU G80-4T to push out the chute. It barely left a mark on the Nomex pad.

I repaired the rocket and launched her again today with the other one of G80's I bought at the same time from the same Hobby Shop. Same story again, very weak charge, chute did not deploy and down we came again. Luckily a tree broke the fall so instead of another complete rebuild I'm only looking at fixing some loose fins...
This charge seemed to be even weaker than the previous one, almost no mark at all on the Nomex, not even enough oomph to kick the babypowder off of the ejection end of casing.
Motor #002245, the previous one I unfortunately discarded, but #'s must be close being shipped in the same batch...

After that one I built a G77-7R redline LMS #011526 all by the instructions using 5min epoxy, let it cure in the warm FL sun a good 20 additional minutes before loading it in my 'Solaris'.
Launch started nominal, but about 350'-400' up the motor CATOed completely blowing out the nozzle, splitting the phenolic casing and burned the living crap outta the guts of my rocket.
Top 6" of motor tube is totally roasted, baffles are gone and two cr's are charred badly. Whoopie....

Anyone else had problems with these or am I blazing a new trail again (according to Gary I was the first one to cato a new style G80 a bit over two years ago, and did it while Turner Broadcasting was filming us and it went national...)

 

[roadkill]

Here's the damage from the first time:

https://www.drsuesrocketworks.com/sitebuilder/images/P10100393-386x281.jpg

 

[roadkill]

And the very light mark on Nomex:

https://www.drsuesrocketworks.com/sitebuilder/images/P1010043-384x281.jpg

 

[roadkill]

Here's a pic of the non-existing mark today, not
even enough charge to blow the babaypowder off the Nomex:

https://www.drsuesrocketworks.com/sitebuilder/images/P1010086-398x293.jpg

 

[roadkill]

Here's a pic of 'Solaris' launching on G77-7R LMS,
all looks good off the rod...

https://www.drsuesrocketworks.com/sitebuilder/images/P1010088-177x247.jpg

 

[roadkill]

Here's a pic of the catoed motor:

https://www.drsuesrocketworks.com/sitebuilder/images/P1010093-319x231.jpg

 

[roadkill]

And another view...

https://www.drsuesrocketworks.com/sitebuilder/images/P10100952-248x177.jpg

 

[roadkill]

Thats three motors lost
and two rockets damaged
(one of them twice) in three
consecutive launches within
a month.

Absolute 100% attrition rate, and
methinks I have every right to be
extremely ticked off right now for
doing (and paying for) research and
quality control work someone else should
have completed before these motors shipped out...

From now on I'll stay with traditional reloads that
I have way over a hundred launches on with 100%
success rate,
at least I have more control in how the motors are
built and know exactly how much ejection charge is used...

Edit: I'll file MESS reports later tonight...

 

[Donaldsrockets]

Sorry to hear that Susan.

I was really thinking about trying out the G77R LMS myself, now I'm not so sure I want to.

 

[RandyM]

At a launch last month, I saw 3 of the LMS motors and the all CATO'ed. I think I'll avoid them for a while until At gets the bugs worked out.

 

[ben]

Originally posted by roadkill
During our THOR Dec.2006 launch I had my spanky new
rocket, 'Pinknose Craypuppy' come down ballistic due to too weak
of an ejection charge on AT SU G80-4T to push out the chute. It barely left a mark on the Nomex pad.

I repaired the rocket and launched her again today with the other one of G80's I bought at the same time from the same Hobby Shop. Same story again, very weak charge, chute did not deploy and down we came again. Luckily a tree broke the fall so instead of another complete rebuild I'm only looking at fixing some loose fins...
This charge seemed to be even weaker than the previous one, almost no mark at all on the Nomex, not even enough oomph to kick the babypowder off of the ejection end of casing.
Motor #002245, the previous one I unfortunately discarded, but #'s must be close being shipped in the same batch...

After that one I built a G77-7R redline LMS #011526 all by the instructions using 5min epoxy, let it cure in the warm FL sun a good 20 additional minutes before loading it in my 'Solaris'.
Launch started nominal, but about 350'-400' up the motor CATOed completely blowing out the nozzle, splitting the phenolic casing and burned the living crap outta the guts of my rocket.
Top 6" of motor tube is totally roasted, baffles are gone and two cr's are charred badly. Whoopie....

Anyone else had problems with these or am I blazing a new trail again (according to Gary I was the first one to cato a new style G80 a bit over two years ago, and did it while Turner Broadcasting was filming us and it went national...)

stick to RMS

thanx, Ben

 

[roadkill]

Originally posted by randym
At a launch last month, I saw 3 of the LMS motors and the all CATO'ed. I think I'll avoid them for a while until At gets the bugs worked out.

If that's the case, Aerotech needs to take this
s**t off the market immediately, go back to their
R&D drawing board and pay us for all the damages caused.

Obviously an unsafe, halfbaked product released in public
for beta testing and needs to be recalled at once....

 

[n3tjm]

Thats why I only use the Reloadable. I see G80's cato quite often; and the G77's are new...

 

[Stymye]

don't forget the mess forms for all those events

 

[jraice]

Are more LMS having issues then SU?

They are the same design so it shouldn't be more risky... You just assemble the LMS yourself...

 

[Donaldsrockets]

I saw a G80 CATO at a launch earlier this month.

According to the guy when I talked to him, his 38/29 adaptor was destroyed but the rocket itself wasn't damaged in any way.

I have one more F42T Econojet and once I use it, that will most likely be the end of AT single use for me. Although I haven't had any problems, except with some Ecatojet G35s, I figure that it's probably best to quit while I'm ahead.

I have two 29/40-120 casings and a 29/60-100 system and I'm sure I'll pick up a 29/120 casing also.

I've always preferred reloads over SU anyway.

 

[Donaldsrockets]

Originally posted by jraice
Are more LMS having issues then SU?

They are the same design so it shouldn't be more risky... You just assemble the LMS yourself...

Sounds like the casing material may be suspect.

In that case, the motor will fail regardless of who assembled it.

 

[roadkill]

'Sounds like the casing material may be suspect.
In that case, the motor will fail regardless of who assembled it.'


I'd like to point that with LMS you assemble the top half of the motor, what failed was the bottom end that is factory made...

...and yes, it does look like the phenolic casing is the culprit.

 

[kelltym88]

Sorry to hear that. What is AT going to do? This is assuming you've contacted them.

 

[roadkill]

Lets see,

They got the ball now...

Gary and Craig usually stand behind their warranty, that'll cover the motors. We'll see what happens with two busted rockets...

 

[ben]

Put me on the list for a CATO'ed G80 Not mine but I saw one <font size="1"> another one </font>.

thanx, Ben

 

[jsdemar]

Originally posted by stymye
don't forget the mess forms for all those events

Motor failures can be reported online at:
https://www.nar.org/NARmessform.html

 

[shreadvector]

Motors with manufacturing dates from 2 days before NARAM and onward should be using the new 'improved' 29mm casings. I have not seen one of these fail, but I've seen plenty of the earlier casings fail (I don't have a percentage, but it is low but anything above zero is annoying).

I'm surprised that the LMS would be failing and I'm assuming that they use the newer casings.

They use the two-lead igniters instead of Copperheads, don't they? Any chance the nozzle got clogged and the motor overpressurized? Probably not, since that would have happened on the pad and not in the air......

Definitely report everything to M.E.S.S. and the manufacturer. Aerotech loves to get the corpse of the casing as well to do analysis, so if they want it, they will give you shipping instructions. Their replacement of the motor is relatively fast (with ground shipping taking most of the time).

I saw a bad flaming rocket death failure of an RMS motor yesterday. Obviously an error on the part of the assembler. Expensive error. Very expensive.

 

[Pem Tech]

Originally posted by roadkill

After that one I built a G77-7R redline LMS #011526 all by the instructions using 5min epoxy, let it cure in the warm FL sun a good 20 additional minutes before loading it in my 'Solaris'.
Launch started nominal, but about 350'-400' up the motor CATOed completely blowing out the nozzle, splitting the phenolic casing and burned the living crap outta the guts of my rocket.
Top 6" of motor tube is totally roasted, baffles are gone and two cr's are charred badly. Whoopie....

Anyone else had problems with these or am I blazing a new trail again (according to Gary I was the first one to cato a new style G80 a bit over two years ago, and did it while Turner Broadcasting was filming us and it went national...)

Susan,
Funny you should bring this up, had a G77R go *POP* on me yesterday.
At ignition it sounded like the motor was going up to pressure but then *POP*! A dense cloud of white smoke issued forth from the motor mount, but no lift off.
Upon inspection it was found that everything AFT of the thrust ring was blown completely off, the case split up the side and the fuel grains were partially forced from the casing.
Luckily the rocket was completely undamaged.


On the second attempt, I was feeling brave that day, the G77 lit off like a champ and roared away spewing that beautiful flame.

Is there a special address at AT to send the motor back for replacement?

 

[shreadvector]

Never mail any motor or motor componenet without clear instructions on how to mail it, what components can be mailed, and exactly who to address it to.

https://www.aerotech-rocketry.com/

https://www.aerotech-rocketry.com/customersite/warranty/warranty.html

Originally posted by Pem Tech
Susan,
Funny you should bring this up, had a G77R go *POP* on me yesterday.
At ignition it sounded like the motor was going up to pressure but then *POP*! A dense cloud of white smoke issued forth from the motor mount, but no lift off.
Upon inspection it was found that everything AFT of the thrust ring was blown completely off, the case split up the side and the fuel grains were partially forced from the casing.
Luckily the rocket was completely undamaged.


On the second attempt, I was feeling brave that day, the G77 lit off like a champ and roared away spewing that beautiful flame.

Is there a special address at AT to send the motor back for replacement?

 

[Pem Tech]

Originally posted by roadkill
Here's a pic of the catoed motor:

https://www.drsuesrocketworks.com/sitebuilder/images/P1010093-319x231.jpg

OK, this is spooky....
That is almost the EXACT failure my G77 experienced, even down to the single large section of phenolic casing being blown off.

*Insert Twilight Zone Music here*

 

[TWRackers]

Originally posted by Pem Tech
*Insert Twilight Zone Music here*

Can't insert it, but you can find it here.

 

[Pem Tech]

Originally posted by TWRackers
Can't insert it, but you can find it here.

Hey, how about the theme to "Rawhide"?

 

[TWRackers]

Originally posted by Pem Tech
Hey, how about the theme to "Rawhide"?

Oh please, don't get that image in my mind. I'm going to be spending a lot of Saturday at the Florida WinterNationals walking to retrieve my rockets. I think you see where I'm going with this....

 

[rocketking]

I have had very inconsistant delay times with AT SU motors. Think I'll have to leave them on my shelf until I feel more comfortable with AT!