Popular Science article

Jerry Irvine wrote:


How would any single individual be able to know all the reasons, for all the catos involving many different circumstances?
Why do your motors cato?
Go from there.
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Because you "made" them?
At least that is what you have claimed right here.
--
Jerry Irvine, Box 1242, Claremont, California 91711 USA
Opinion, the whole thing. <mail to: snipped-for-privacy@gte.net>
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wrote:

Would you like to replace the last Bittkicker reload I have? It has big bubbles in it. It's the CATO that hasn't happened yet.

I was there. That was Bob Utley's rocket. Why don't you check with him and see what he says. The you can come back with your analysis.
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Phil Stein wrote:

The "real photos" of that particular CATO are available at the MDRA web site:
http://www.mdra-archive.org/photos/LDRS23/Full/jr-IMG_1101.JPG
http://www.mdra-archive.org/photos/LDRS23/Full/Flame_in_my_eye.jpg
http://www.mdra-archive.org/photos/LDRS23/Full/jr-IMG_1110.JPG
and the rocket destroyed just minutes earlier by a CATO of another motor from the same batch:
http://www.mdra-archive.org/photos/LDRS23/Full/jr-IMG_1009.JPG
http://www.mdra-archive.org/photos/LDRS23/Full/IMG_1104.JPG
http://www.mdra-archive.org/photos/LDRS23/Full/IMG_1105.JPG
...Rick
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rick:
I wonder why so many HPR seem to cato? Does anybody have an idea? Does anybody fill out a NAR MESS or TRA equivalent, when these catos's occur. I would submit, that everytime there is a cato, some form of report should be made and made available to the rocketry community, perhaps online or in the respective org's publications?
shockie B)

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Shockie...
Didn't NAR just form a committee to looking in to the increase in flight problems at their launches? (including non HP) Seems they're even including one or more people from TRA.
It doesn't seem the committee was formed due to "cato" problems..
I'll say that the vast majority of "cato" problems I've seen in the past have not been a manufacturing problem, but a user problem.
(often temp stressed BP motors or poor assembly of an reloadable or the setup of electronics..)
Filing a MESS when ever there's a cato is probably a bad idea, as often the post mortum will indicate another problem. "Darn, I forgot to tell the electronics the right delay for mach inhibit!" (this realization might come a few days after the launch!) or "darn - the ematch for the ejection charge came loose"
Remember the "boy that cried wolf" - filing a MESS on every cato may diminish the meaning of the MESS.

I
be
the
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shockwaveriderz wrote:

Hi Shockie. The one in the first picture of the PopSci article was definitely an EX M motor. And it was almost expected to CATO, as another from the same batch, in someone else's rocket, had CATO'd minutes earlier.
And what do you mean by "so many"? I've never thought of the CATO rate, except for that one summer with the bad AT J350 grains and the QC problem plaguing CTI, as being particularly remarkable. As for why at a particular event, well the more motors we burn, the more motors (number-wise) are going to CATO.
LDRS 23 had a lot of commercial motors burned over four days, and because it's LDRS the projects are a little more extreme, so you'd expect more than the normal number of CATOs than at a typical weekend launch. Why do HPR motors CATO at all? Well, lots of reasons, including but not necessarily limited to overly energetic igniters, cracked grains, plugged nozzles, improper assembly, parts fatigue, etc.
I've had three mid-power / HPR CATOs myself, and frankly, I never submitted a formal report. One was an old G80, which failed longitudinally and didn't damage the rocket. One was an F50 which, on post-flight reflection, was my fault, as I'd left one motor in the cluster resting on the blast deflector, plugging its nozzle. And the third, an M1419, blew out half its nozzle in flight, presumably due to an unnoticed pre-flight fracture. That CATO was reported to Aerotech, who replaced the hardware and the reload.
...Rick
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all I am saying is the article seems to "highlight" catos, otherwise know as explosions. Its accentuating the bad or negative aspects of the hobbysport. I can't see how highlighting explosions helps HPR or TRA EX or AR or MR....
Yeah I know, catos aren't "technically explosions, or at least most aren't" but to the casual bystander what they see and hear is an explosion.
So this casual observer than associates "explosions" with all forms of rocketry as cato's happen the entire spectrum of rocketry from micro maxx to M and beyond. And it seems prevalent in EX more so than Commercial.
That article would have been much better if some of this was pointed out or explained.
shockie B)

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Especially since according to Ray Dunakin, "they are mostly EX".
This points out the need to have a HARD LINE betweeen pre-approved consumer rocketry and amateur rocketry (TRA munges it to a term "EX").

Jerry
--
Jerry Irvine, Box 1242, Claremont, California 91711 USA
Opinion, the whole thing. <mail to: snipped-for-privacy@gte.net>
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Jerry Irvine wrote:

duh, jerry, that's why your motors and propellant are not allowed at EX launches.

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Dave Grayvis wrote:

Forget it Dave, "big fine' can't comprehend factual reason..
Fred
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Have you sent a letter to the editor telling him that?
On Tue, 12 Jul 2005 03:28:39 GMT, "shockwaveriderz"

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shockwaveriderz wrote:

Most, perhaps all, of the catoes reported in the PopSci article were of EX motors, not commercial motors. EX motors are, as the name implies, experimental.

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I
be
the
Have you filled out one of the four NAR mess forms for your CATOS with Estes motors this year ?
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almax:
catos' from an MR A3-4T and an TRA EX "M" class motor is several orders of magnitude in difference I think you might agree.
It really doesn't matter as the TRA ignores its own NFPA1127 Safety Code anyway when it comes to TRA EX.
From NFPA 1127:
Chapter 1 Administration
1.2.2 The purpose of this code shall be to establish guidelines
for reasonably safe operation of high power rockets to protect
the user and the public.
1.2.3 The purpose of this code shall be to discourage the
following to minimize deaths and injuries:
(1) Experiments with explosive or highly energetic rocket
propellants
(2) Construction of homemade rocket propulsion motors
(3) Attempted launches or operation of homemade rocket devices
It seems to me that ALL of the above describe TRA EX. I don't see the TRA discouraging any of the above activaities in fact they promote TRA EX to their membership, in apparent violation of their own HPR Safety Code. Might I add that Bruce Kelly et al who sit on the NFPA for the TRA evidently has no problem with the above. TRA speaks with a forked tongue.....
As far as the Discoovery Channel and this Popsci article being so good for the rocketry community as a whole, perhaps it just attracted those that to see and hear things that go BOOM?
Somebody in the TRA that has the BALLS to ask the TRA leadership on their listserver should enquire about the above and ask TRA how they reconcile their own HPR Safety Code admonishing against EX, how then the TRA can even have much less promote EX?
Now I understand Bruce Kelly's RANT about why the NFPA code should not apply to AR (which TRA EX is ).. Maybe he's just against NFPA codes for TRA EX? hmmmm....
Wheres LunarLos when you need him? You talk about NAR Hyprocrisy , this is a massive example of Hyprocrisy by the TRA !
shockie B)

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Hi Shockie, you can call me Al.

Nope, a Mess form is a Mess form. that's what I was talking about, not the CATO itself.
Did you fill one out this year ? I will be from now on since I read the request from S&T.

I hope it does. We got more members in our club, good ones that figured out how to do things better then some of the older club members.
We like fast cars, guns, monster trucks and good looking women as well !
Can't wait to watch master blasters during naram week on wednesday. Hope it's one each week.

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On Tue, 12 Jul 2005 19:56:51 GMT, "shockwaveriderz"

Yea. People get real clost to the A3 and have no clue that it can also come apart.
1127 does not apply to EX. EX generally has increased safety distances. Didn't you notice that people don't get injured in either circumstance.
any more words of wisdom king weenie?
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NFPA 1127 doesn't apply to TRA EX?
well of course it applies you TRA weenie, here let me re-post what NFPA 1127 says:
From NFPA 1127:
Chapter 1 Administration
1.2.3 The purpose of this code shall be to discourage the
following to minimize deaths and injuries:
(1) Experiments with explosive or highly energetic rocket propellants
(2) Construction of homemade rocket propulsion motors
(3) Attempted launches or operation of homemade rocket devices
Doe not the above 3 items describe TRA EX to a "T". ?
TRA should be discouraging TRA EX instead of embracing and trying to popularize it....
we all know that TRA EX is just a "veiled" attempt at including AR under TRA jurisdiction....Its just another "marketing" tool the TRA uses to recruit members....
Join the TRA where we never met a Safety Code we didn't like.....or follow....or enforce
shockie B)
wrote:

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On Wed, 13 Jul 2005 21:03:21 GMT, "shockwaveriderz"

Read these and then explain why they aren't the same.
http://www.tripoli.org/documents/ex_safety_code.pdf
http://www.tripoli.org/documents/safety_code.shtml
Did you notice the increased Safety Distances as well as other 'features' to protect people in case there are problems.
The EX safety code is so safe, I'd even attend a launch where weenies like you have made their own motors.
Zero of the top 3 flights at last years LDRS that gave me the most concern were EX motors.
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Yet they were on the cover of Popular Science and overshadowed and gave HPR a bad name.
You cannot unring a bell.
--
Jerry Irvine, Box 1242, Claremont, California 91711 USA
Opinion, the whole thing. <mail to: snipped-for-privacy@gte.net>
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