E16 catos?

[kuririn]

For the second weekend in a row I've had an Estes BP E16-6 cato in a rocket. Already filed the MESS report, but I'm wondering if anyone else has had this problem? The engine(s) ignited, but did not develop any thrust to lift the rocket and instead burned like a blowtorch on the pad. The deflector plate on my Porta Pad E burned through and the flame ignited the plastic base. The plastic was still burning when I retrieved the rocket off the pad. It appears from the lot # that the engines were manufactured five years ago and I purchased them about 3 1/2 years ago. They were kept indoors in a cardboard box, temperature ranged no more than 95 deg F to 62 deg. F. Will contact Estes cust. svc. for a replacement pad and motors. I know about the 24mm E9 reputation, but never heard about a problem with the E16. Comments?

 

[Rocketjunkie]

What was the temperature when you tried to launch? I haven't used any E16s but I've flown lots od F15s with no failures (yet).

 

[kuririn]

What was the temperature when you tried to launch? I haven't used any E16s but I've flown lots od F15s with no failures (yet).

I would say around 72 deg.

 

[Wallace]

What do the nozzles look like on the "fired" motors?

 

[kuririn]

Most of the clay is gone, just a large hole and some residue. Don't have a pic cuz they've been chucked.

 

[Wallace]

Do you have any left from the same lot? Sounds like it might be due to nozzle failure to me...

 

[lakeroadster]

Man that sucks! Their are E9's and E12's on the list but not E16's.

When you talk to Estes ask them to make available to us a list.. like the one below. That way we could avoid engines with historically bad date codes.

Since that ^^^^ probably will never happen, I'll start a thread and create a spreadsheet. Folks can post bad date codes and I'll update the spreadsheet.

If you pay for air fare I'll bring over my Launch Horse ;-)

 

[Steve Shannon]

Do you have any left from the same lot? Sounds like it might be due to nozzle failure to me...

That’s exactly what it sounds like to me also. No nozzle, no pressure, no thrust.

 

[kuririn]

Lake: The lot # was A 04 15 13. Where can I enter it?

Wallace: Couldn't find any more E16-6s, but here's a pic of the back end of an E16-4 from the same lot#:

Would a visual examination disclose any deficiencies, or is that a materials failure? (i.e. can one tell a good nozzle from a bad one prior to use by visual inspection?).

 

[Charles_McG]

Reports of Estes 29mm BP motors CATOing have been relatively rare.
I just did a quick search of Rocketreviews flight logs and found 1 CATO in 18 records. Small sample.

Rocketreviews flight logs are the only handy place I've found to get an idea of CATO rates, since the users will note CATOS in the log notes.
Alas, the motor summary page has been updated recently, and doesn't show the comments in the grid view anymore. That made it easy to count them up.

 

[lakeroadster]

Lake: The lot # was A 04 15 13. Where can I enter it?

Wallace: Couldn't find any more E16-6s, but here's a pic of the back end of an E16-4 from the same lot#:
View attachment 372270
Would a visual examination disclose any deficiencies, or is that a materials failure?

I created a new thread... https://www.rocketryforum.com/threads/suspected-bad-motor-list.150501/#post-1852295

 

[cwbullet]

All motors have CATOs but having two in one pack makes me suspicious that it is a bad batch or the motors were stored in extreme temperatures. I know both will increase the odds of a CATO. The MESS report will help track batches to determine if there is a bad batch. The temperature extremes can happen before you purchases the motors.

 

[shreadvector]

I've seen some assorted D12 and E9 motors 'pop' the nozzle at ignition and just sit there on the rod with a highway flare flame coming out the open bottom end of the casing. This will destroy plastic launch pads. You can often hear the "PING" of the nozzle popping out and hitting the deflector before it bounces away.

Very rare these days, but was more often seen in the 2006 time frame (era of the Phoenix NARAM 48) and a few years afterward.

I have seen this in C6 and A8 motors that had signs of water damage. We were handed some 'leftover' motors by a teacher and the bulk motor boxes showed signs of past water exposure and some of the motor nozzles were very swollen (even though they were now dry). When fired, almost all of the motors spit out their nozzles at ignition and sat there. The rest became gopher gassers.

 

[shreadvector]

I've seen some assorted D12 and E9 motors 'pop' the nozzle at ignition and just sit there on the rod with a highway flare flame coming out the open bottom end of the casing. This will destroy plastic launch pads. You can often hear the "PING" of the nozzle popping out and hitting the deflector before it bounces away.

Very rare these days, but was more often seen in the 2006 time frame (era of the Phoenix NARAM 48) and a few years afterward.

I have seen this in C6 and A8 motors that had signs of water damage. We were handed some 'leftover' motors by a teacher and the bulk motor boxes showed signs of past water exposure and some of the motor nozzles were very swollen (even though they were now dry). When fired, almost all of the motors spit out their nozzles at ignition and sat there. The rest became gopher gassers.

Never seen any E16 or F15 motors spit a nozzle. Saw one E16 that had a blow through part way through the burn (maybe the half-way point). All others worked SUPERBLY.

 

[mccordmw]

I thought the Estes E motors were legendary for CATOs. I've only seen a few CATOs at launches I've attended, and they've always been one of the Estes E motors. A search of these forums turns up lots of posts on them.

I've flow a ton of Estes F motors without ever having an issue. I avoid E motors like the plague.

 

[Charles_McG]

I thought the Estes E motors were legendary for CATOs. I've only seen a few CATOs at launches I've attended, and they've always been one of the Estes E motors. A search of these forums turns up lots of posts on them.

I've flow a ton of Estes F motors without ever having an issue. I avoid E motors like the plague.

The 24mm Es have had some bad lots.
The 29mm Es and Fs have had far fewer reports.

 

[Wallace]

I have one left from the same lot. Flew the other one the year before last without issue. Guess I'll have to fly this one in something I'm not particularly attached to...

 

[BDB]

My daughter had a 29 mm F15 blow the nozzle out this weekend. It flew about 15 ft in the air and then did a great impression of a road flare. Minimal damage to the rocket. This is the first issue we have had with an Estes 29 mm motor.

 

[Bat-mite]

Lake: The lot # was A 04 15 13. Where can I enter it?

Wallace: Couldn't find any more E16-6s, but here's a pic of the back end of an E16-4 from the same lot#:
View attachment 372270
Would a visual examination disclose any deficiencies, or is that a materials failure? (i.e. can one tell a good nozzle from a bad one prior to use by visual inspection?).

Can't answer your question, but you could take the one you have, stick it in a vise, and light it. See if it burns correctly or blows out the nozzle. Film it, and if bad, send it to Estes.

 

[Steve Shannon]

Lake: The lot # was A 04 15 13. Where can I enter it?

Wallace: Couldn't find any more E16-6s, but here's a pic of the back end of an E16-4 from the same lot#:
View attachment 372270
Would a visual examination disclose any deficiencies, or is that a materials failure? (i.e. can one tell a good nozzle from a bad one prior to use by visual inspection?).

On the form it’s the third line down right below engine type:

 

[kuririn]

Thanks Steve, I already filed the MESS report. I was referring to Lake's list of motor CATOs.

 

[kuririn]

Wow, that was fast. Just got an email from Sandra at Estes customer service. They are replacing my motors and launch pad. Impressive!

 

[Steve Shannon]

Thanks Steve, I already filed the MESS report. I was referring to Lake's list of motor CATOs.

Ahhh, sorry, I misunderstood. Hopefully someday users will be able to see the data in the MESS reports and generate reports based on motor types and date codes. Until then I applaud the efforts to collect data like this.

 

[Andrew_ASC]

I've flow a ton of Estes F motors without ever having an issue. I avoid E motors like the plague.

I flew two E12-4’s in a Estes Conquest last year. The newer batches are good. I did buy a AT RMS 24/40 and a E-18W three pack. I wouldn’t blame the E class. Estes just had problems with quality control in the past. I feel the APCP motors are more consistent from batch to batch.

 

[mccordmw]

I flew two E12-4’s in a Estes Conquest last year. The newer batches are good. I did buy a AT RMS 24/40 and a E-18W three pack. I wouldn’t blame the E class. Estes just had problems with quality control in the past. I feel the APCP motors are more consistent from batch to batch.

I'll clarify. I avoid the Estes BP E motors. I have a bunch of AT Es and happily fly those. I think it's just the BP and the susceptibility to fracture, maybe. Who knows, but I won't risk my models on a motor that I've heard too many bad stories about (the Estes BP Es). It's easy to lose customer faith and hard to restore.

 

[Andrew_ASC]

No I respect that. We dig through four hundred pages of black powder faults in Taketa airbags because a lab didn’t test for so many variations in humidity while at university for a graduate level auto engineering course. The humidity was causing fractures of the propellant and excited combustion values in some cases not lab tested. I wondered to my self if similar errors were causing Estes catos.

 

[shreadvector]

I'll clarify. I avoid the Estes BP E motors. I have a bunch of AT Es and happily fly those. I think it's just the BP and the susceptibility to fracture, maybe. Who knows, but I won't risk my models on a motor that I've heard too many bad stories about (the Estes BP Es). It's easy to lose customer faith and hard to restore.

Many R&D reports have proven the the catos are not caused by propellant grain cracks or fracture.

Zero.

To crack the grains, you must hit the side of the motor with a hammer while it is laying on concrete.

Failures are the mechanical bond of the propellant grain to the cardboard casing. Also, the bond of the nozzle to the cardboard casing.

Temperature cycling was tested. Humidity cycling was tested. motors were tested while hot and while cold and after being subjected to 100% humidity for a month.

The nozzle popping out failure mode is relatively new. I'm curious as to the cause in new motors, but I know that old motors that have been 'wet' and then dried will do this.