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.
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:
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)
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.
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
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)
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>
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.
†
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)
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.
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?
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:
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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