When Was YOUR First CATO?

[ScrapDaddy]

I Have Heard about them but i have never seen one.... i heard they are Pretty Spectacular
When Was Your First CATO, the story behind it and hopefully...... :wave::wave::wave: Pictures:y:

 

[new2hpr]

I have yet to have one (though now I've jinxed that). I did have 3 Estes E9's simultaneously pop their nozzles out on a cluster launch. It just sat there burning on the pad. Minor damage and flying again, but embarassing!

Sorry, no pix.
-Ken

 

[tbzep]

First two were Estes C5-3's, each one was in my Centuri Saturn 1B in the early 1980's on separate flights. I repaired it the best I could after each bang. The third one was a D12-3 in my BT-80 upscale Goblin and another in an old Big Bertha, but I don't recall the motor. Both were repaired and flown a lot afterwards. I believe that's all I've had, but I've witnessed a few Estes E15's and several motors from FSI.

Edit: I wasn't even thinking about APCP motors. I've had a few, the largest being a blown EX M3000 nozzle at Orangeburg, I think around the July 4 weekend in 1997.

 

[Rocketjunkie]

I flew about 1000 flights in the early 70's using Estes, Centuri, FSI, and Enerjet in sizes 1/4A-F. I never had a cato. I got back into rocketry in 1988 when I found out about high power. One of the first things I did after the return to rocketry was a small 2 stage 'fire and forget' rocket with D12s. The booster blew both ends, also destroying the fins on the sustainer but the sustainer still lit and pinwheeled away. That was my first cato, but by no means my last The last was an M at Orangeburg last September https://www.tripolisc.org/modules/xoopsgallery/cache/albums/albun92/45a.jpg

 

[RoyAtl]

I Have Heard about them but i have never seen one.... i heard they are Pretty Spectacular

Here's a full-blown (bad choice of words!) example:

 

[SecretSquirrel]

Okay, here's my first CATO, it's the boilerplate model for our Metropolitaln Police Call Box.

And here's the motor, a single use E30

 

[MarkII]

Sometime in the unforeseeable future. They aren't all that common. I have never seen one, either.

MarkII

 

[ScrapDaddy]

MArkII? You Have Never had one?

 

[MarkII]

MArkII? You Have Never had one?

No. Have you? They are very infrequent. As I mentioned above, I have never seen one, either.

MarkII

 

[ScrapDaddy]

Okay, here's my first CATO, it's the boilerplate model for our Metropolitaln Police Call Box.

And here's the motor, a single use E30

How did you find all the pieces of the motor?

 

[ScrapDaddy]

No. Have you? They are very infrequent. As I mentioned above, I have never seen one, either.

MarkII

But You Have Been In rocketry for such a long time....... And have Been Lucky:dark: I just really want to see one

 

[ScrapDaddy]

CATO;s are things we heear about but we never seem to see

 

[The EGE]

I've flown close to 200 motors, about 3/4 blackpowder, in the last 18 months. No CATOs.

 

[ScrapDaddy]

I have heard that most people had their first CATO on BP motors due to their brittle nature

 

[CF-105]

First one was a D12-3 in my Estes Optima, roughly 10-12 years ago. Ripped the motor mount right out of the rocket and pinwheeled in the air 'til it burned out.

Since then, I've had a couple of single-use D21's go, and one 24mm F. Had a Pro38 G blow a few years back due to using the wrong e-match (error by their supplier or something). And "operator error" wrecked an H123 And an I161 back when I was just getting into HPR (two of my first 3 RMS motors!).

Needless to say, these days I am extremely careful when assembling motors!

 

[terryg]

A few months ago, not quite the effect I was going for, but interesting nonetheless.

https://www.rocketryforum.com/showthread.php?t=8033

 

[ScrapDaddy]

Oh I remember that thread

 

[RoyAtl]

I have heard that most people had their first CATO on BP motors due to their brittle nature

Well, the common cause for black powder catos is not cracks in the propellant -- The pressed grain itself is pretty sturdy -- but separation between the black powder grain and the casing, or the nozzle.

This is most often caused by thermal expansion differences; i.e. the grain expands and contracts with temperature at a different rate than the casing or the nozzle material. The motor usually has to be exposed to temperature extremes, i.e. closed car in summer vs freezing garage in winter. Visually, you can't tell if there's a problem. These separations are microscopic in nature. But once the flamefront reaches the separation the flame propagates along the exposed surface, creating more gas than the casing or nozzle were designed for, and something has to give.

AP catos are more often caused by structural problems. Bad single-use casing, or o-rings that have been screwed up (either single use or reload), or epoxy joints that give way in single-use motors.

 

[MarkII]

If I have been lucky, then a great number of other rocketeers have been lucky, too. But odds are that you will never see one, either, unless you attend several large rocket festivals each year, and you are at the range head to view every launch. Millions of rocket motors are fired every year. Only a tiny fraction of them fail. You are extremely "lucky" (if you can call it that) if you ever happen to catch one. The few manufacturers that are still around produce extremely reliable rocket motors. In the past there were many more companies producing them, and the reliability of some of those products was a bit more sketchy; even Estes had its problems with a couple of its motors. Motors that are assembled by hand are more prone to failure than those that are machine-produced, just because there are more opportunities for error in the process. Since nearly all high power motors are assembled by hand, the odds of having a failure with them are greater. I have only been present for the launch of a high power rocket once, and it was nominal. But even with HPRs, the rate of motor failures is pretty darned low from what I understand.

Many veteran rocketeers can recount stories of their own or others' motor failures because they were around when some of those less-than-perfect motors were on the market. I never had the pleasure.

BTW, I have been launching rockets for a total of about 10 years: for 4 years back when I was a kid, and around 6 years as a BAR.

MarkII

 

[ScrapDaddy]

It Is Pretty Darn Cool to see one from the pictures iv seen on EMRR

 

[stickershock23]

I Have Heard about them but i have never seen one.... i heard they are Pretty Spectacular
When Was Your First CATO, the story behind it and hopefully...... :wave::wave::wave: Pictures:y:

Not my first, but spectacular....

You asked for it..

I've had worse... Case burn through's Forward closures burnt through
nozzle failures... fly enough and it happens. seems my record is getting way better now that I changed brands..

Oh an my second favorite.. not my rocket but still worth posting.

I don't think I've been to a launch and NOT seen a failure.. for those who say they have never seen them, can I come fly with you.. or at least have you rub my rocket before I do.... Dang that sounded just WRONG.. LOL

 

[ScrapDaddy]

HOLY CRAP!!!! THAT IS PRETTY DARN SPECTACULAR!!!! And what rocket was that?(it looks like a loc onyx)

 

[Donaldsrockets]

IIRC, mine was with an A10-3T. It literally blew an Estes RTF Mini Marz Lander to bits!!!

Instead of the typical woshhhhhhh, it sounded like a .22 caliber round going off.

Surprisingly the nozzle was still intact. Everything just blew right out the top. I bagged up all the pieces and sent it back to Estes and they promptly replaced it and also sent a pack of A10-3T's with it.

I also had a C5-3 CATO but it didn't damage the rocket at all. I also had some Estes E15's CATO but they were highly known for that.

That's why they make the E9 today. It operates at a lower pressure than the E15 did. Unfortunately the initial thrust and overall motor performance suffers because of it. The E15 also had a VERY small nozzle, about half the size of the current E9 nozzle.

 

[hcmbanjo]

Thinking back it would have to be in the early 1970s flying my Estes Goblin on a D13-5.
About three feet above the launcher it fire-balled, right through the body.
It blew the nose cone off, there wasn't much left of the streamer or shock cord. That fireball reamed out the body tube, charring it up pretty good.
Those early D engines were designated 13 for a reason.

 

[ScrapDaddy]

Well thats What The AT E15 is for

 

[ScrapDaddy]

Not my first, but spectacular....

You asked for it..

I've had worse... Case burn through's Forward closures burnt through
nozzle failures... fly enough and it happens. seems my record is getting way better now that I changed brands..

Oh an my second favorite.. not my rocket but still worth posting.

I don't think I've been to a launch and NOT seen a failure.. for those who say they have never seen them, can I come fly with you.. or at least have you rub my rocket before I do.... Dang that sounded just WRONG.. LOL

Wow Nice lawn Dart I Had 3 In a row! with the SAME ROCKET!!! (i was experimenting with anti zipper designs... it worked.... in the wrong way

 

[MarkII]

The photos of catos that are on the web are there precisely because those motor failures were spectacular. Not all of them are as visually dramatic as those. I have seen photos and web videos of catos that appear to an onlooker to be nothing more than a muted "pop." And I have read accounts of motor catos that hardly did any damage to the rocket. From what I hear, many (perhaps most) catos aren't caused by casing failures; a great many are caused by end closure failures or nozzle failures. A nozzle failure may not cause any damage to the rocket at all.

MarkII

 

[stickershock23]

Wow Nice lawn Dart I Had 3 In a row! with the SAME ROCKET!!! (i was experimenting with anti zipper designs... it worked.... in the wrong way

Yeah, this one was a stock Sumo. Motor catoed failed to eject and came in just as you see it.. flaming and all.

Again this was not mine. so I cant take credit... but it's a perfect picture LOL

Now the other rocket... yep mine. 75mm M3000 purple experimental Not sure why it cato'd because every test motor we fired did just fine... oh well chalk it up to experience.. at least Ray Lapanse (sp?) caught a perfect shot! I'll never live that one down...

 

[ScrapDaddy]

But WOW!

 

[UPscaler]

I haven't had a cato...yet.


I'm expecting one soon. I flinch every time the countdown gets to one.

so far it has paid off.

I pray my luck doesn't end on my dad's level 1 in my 29/240 case.

blowing up my rocket is bad, but blowing up my dad's would be horrible!


Mark, you are welcome to come to Idaho and fly with all 20 of us. I haven't seen any CATO's out here, but i've only been to a couple launches.