Another E9 CATO... Yowza...

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

lakeroadster

When in doubt... build hell-for-stout!
Joined
Mar 3, 2018
Messages
8,569
Reaction score
10,513
Location
Central Colorado
Stephen Casey Stanford‎ posted this on the NAR Facebook page....

"Sad day. I lost my Estes Super Big Bertha on its maiden flight to an E9-4 cato. It would have survived if it didn’t hit the ground on the forward end of the body tube."

Alpha E Engine CATO.jpg

 
Random question- what is it about the E motors that makes them so problematic that we don't see in the 24mm D BP motors, or the 29mm F15 motors?
 
Do you have the motor code? I still have quite a few E9's in my stash. Also, please file a MESS form on www.nar.org.
Estes is good about replacing the motor and model. Contact their customer service.
I had an E9 spit the nozzle a couple of years ago. Model was not damaged and Estes sent a new pack of motors.

Chas
 
Do you have the motor code? I can add it to my list.

I am puzzled by the video as to what happened. It looks like the rocket left the pad, but the motor exploded at the pad.
 
At naram the flights I saw were about 30% failure of E-9's which is about in line with what my personal experience has been viewing launches of E-9's, of course that doesn't mean I watch every E-9 launch, just the ones I hear and watch.
 
I am puzzled by the video as to what happened. It looks like the rocket left the pad, but the motor exploded at the pad.

That’s how it looked to me also. It took off, then overpressure and forward failure occurred, spitting the motor out aftward.

It seems like the motor is splitting and spitting faster than the eye can see, blowing forward and backward, especially, because there is a vertical smoke-trail going far above the rocket model itself.
 
Please note that the thread starter is not the person who suffered the cato. He was reporting something he saw on Facebook.
 
At naram the flights I saw were about 30% failure of E-9's which is about in line with what my personal experience has been viewing launches of E-9's, of course that doesn't mean I watch every E-9 launch, just the ones I hear and watch.

That's the general observation I hear at LUNAR launches also, about one in 3 fails, for both the E9 and E12. I recall a launch where like the first 6 worked, and the LCO was getting really surprised, then the next few made up for them. :p
 
I sure hope the new Estes owners address this problem its been going on for years. We always say file a MESS report but what is done with the info?
 
I sure hope the new Estes owners address this problem its been going on for years. We always say file a MESS report but what is done with the info?

The MESS reports go into a tabular file that is sent to all the motor testing committee members. I do not get them unless I request them. Unfortunately the information lacks production numbers so it’s difficult to understand what the numbers really mean. The one time I looked at them I didn’t see a huge number of E9 failures.
We see many more anecdotal reports of E9 failures than MESS submissions.
 
I had both E9-4 motors in a cluster fail at NARAM-60. The date code was pretty old. Another person from my club had one old and one newer E9 fail.

Estes has not produced an E9 in "a long time" as they have been superseded by the E12. They confirmed that the failure reports are random as far as date codes are concerned.

Please continue to file M.E.S.S. reports and also report to the manufacturer.

And, while I have seen some E12 failures in the past, I have not seen many recently. Like one in that last 9 months (lots of them flown at our club launches).

Based upon my past R&D report on motor failures for D12-5 motors, I would suspect that the longer grain on a 24mm E can lead to issues when it experiences temperature cycling. The grain will expand in diameter and length more than the cardboard casing and the casing will not shrink back as far as it cools, so the mechanical bond to the casing wall can be compromised.

I am confident that they have applied 'artistry' and 'engineering' to make the E12 more reliable in the long run.

The E16 and F15 are EXTREMELY reliable. If you are afraid of 24mm BP E motors, go to 29mm E and F motors.
 
Do you have the motor code? I still have quite a few E9's in my stash. Also, please file a MESS form on www.nar.org.
Estes is good about replacing the motor and model. Contact their customer service.
I had an E9 spit the nozzle a couple of years ago. Model was not damaged and Estes sent a new pack of motors.

Chas

Yes, please file a MESS Report. A more direct link is motorcato.org.

Do you have the motor code? I can add it to my list.

I am puzzled by the video as to what happened. It looks like the rocket left the pad, but the motor exploded at the pad.

That’s how it looked to me also. It took off, then overpressure and forward failure occurred, spitting the motor out aftward.

Stephen Casey Stanford‎ posted this on the NAR Facebook page....

According to Stephen Casey Stanford the rear nozzle blew out of the engine followed by the ejection charge out the front. He was asked to file a MESS report and also was asked for the motor code. If he posts that data, I'll repost it here.
 
The E9... 2/3 Cato’d on me. I have another pack- I would not wish them on someone I do not like. Frankly, I believe that if Estes, and I am not intending to insult the new owners, should have recalled these motors (should that be spelled grenade?). We can argue all day long about not knowing the denominator of the production, hence not knowing the true percentage of motors that have failed, but many folks have had these fail spectacularly. They are a problem plain and simple. It is good that Estes has stopped making them, but that does not help with the motors already sold or on the shelves.
 
I have 7 of them five E9-6s from 12-1-05 and two E9-8's from 7-02-07, will probably fly them in something disposable. Thanks for reposting the list.
 
I flew one E12-4 in a Conquest at ROSCO then bought an Aerotech RMS24-40 casing. There are better motors than Estes E class. My E12 didn’t CATO but I sure joked it would.
 
Why are E9s still being sold? This has been a problem for me also

They aren’t. Estes just informed me today that they quit making E9s at the end of the year. This is my rocket in the photo BTW. This happened last Tuesday. I gave permission to have it posted here. Fortunately Estes is sending me a new kit and some E12s. [emoji41][emoji106][emoji573]
 
Thank you for sharing this here. It took me some time but I finally found it. I just heard back from Estes today. They have my new Super Big Bertha in the mail along with a pack of E12s. They also told me that they discontinued the E9s at the beginning of the year. That’s probably why I got them so cheap at hobby lobby.
 
Last edited:
Interesting thread (and sad given the losses of course). FWIW Estes E impulse BP motors have never had HSE approval here in the UK, nor were they granted CE rating in the EU. Only AP E's are legal. A lot of us here saw this as regulation gone mad - but given the track record of E9's you're all describing perhaps there was some sort of sense in the bureaucratic madness after all. Anyway, not meaning to hijack or divert the thread - just a footnote. Sorry for all your losses.
 
They aren’t. Estes just informed me today that they quit making E9s at the end of the year. This is my rocket in the photo BTW. This happened last Tuesday. I gave permission to have it posted here. Fortunately Estes is sending me a new kit and some E12s. [emoji41][emoji106][emoji573]

Welcome to the forum Rocketman!
 
Back
Top