ROL NEWS--AeroTech Endorses Consumer Adjustment of RMS Delays

Ok jerry I'll bite....please elaborate on the manufacturing cons.. from my POV the biggest manufacturing con would be, is that they have a known system
in place to mass produce their motors as is..ie combined propulsion and delay train/ejection charge...
I understand how that simplifies the manufactruring proces for making BP motors, as you just run the motors back through the same machinery to put in the delay train/ejection charge.. Does anybody know if these components are premade or are placed into the paper motor casing and allowed to "cure'...
The only was for this to work would be have a different machine somewhat like the motor making machine and instead of making combined motors you now make motors on machine 1 and delay trains/ejection charge modules on machine 2...
But what if you could make a batch of motors..say A3-0 in 13mm and then after you have made the batch motors, instead of loading the machine with 13mm casings you now load with paper casings that fit inside the inner diametr of the 13mm tube and run thriough a batch of delay/ejection charge modules.... one run to make say a 6sec delay..then you offer a tool to change that max 6 sec down to 2 if need be...
I think Estes just doesn't want to sell partial BP motor kits to 14 years old....thats why they stay with their tried and true methodology.....
I know this could be done, but until Estes the market leader decides to change there will be nochange...
shockie B)

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In my opinion you grossly misuse the information you receive. You improperly contact authorities, you threaten to "out" fellow rocketeers for your perception (often wrong or skewed) of violatios (no I am not even talking about me!).
You are a hazard to the industry at large.
Jerry
disengage

--
Jerry Irvine, Box 1242, Claremont, California 91711 USA
Opinion, the whole thing. <mail to: snipped-for-privacy@gte.net>
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jerry:
liar liar pants on fire.
I have never contacted any authorities, properly or improperly , except for my own State Fire Marshall,concerning rocketry here in the State of KY....As far as I am aware, rocketry is still as legal and openly pursued here as it ever has.....
well dude if you aren't the poster child for bad behavior in our hobby then I don't know who is... and yeah I seriously considered "outing" you (are you gay too jerry?) to the California State Fire Marshall about your DOT transgressions, but since the NAR could care less, I decided I cared even less.... I am not aware of any other public violations by anybody else in the hobby..... and yes there are some 'behind the scene" machinations that trouble me, but again my opinion is just like an ahole jerry, everybody has one....and I am not the police....if the NAR/TRA brand of "self-regulation" is not working, its not my job nor responsibility to do their job for them.....IF self-regulation actually worked, you would have been run out of the hobby many moons ago......
As usual you are talking poop with no basis in fact.....
the fact that you are trying to smear me here, and not even bothering to answer my questions, just shows you for what you are: a poor pathetic,loser.....and probably a government agent provocateur
shockie B)

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I have no obligation whatsoever to answer your questions.
--
Jerry Irvine, Box 1242, Claremont, California 91711 USA
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you calling me a hazard to the industry is like calling the kettle black..look in the mirror jerry, the only hazard I see to rocketry is YOU...
shockie B)

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Consider it an expert opinion.

--
Jerry Irvine, Box 1242, Claremont, California 91711 USA
Opinion, the whole thing. <mail to: snipped-for-privacy@gte.net>
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In your "expert" opinion... rocket motors are "model aircraft parts"....
'nuff said..
shockie B)
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This is basicly what AVI did with their "gold series" motors in the mid 1970s. 18mm D6.1 had a 13mm delay insert with the delay and ejection. THe 24mm E11.8 had a 18mm insert. And the 33mm E and F motors used 24mm inserts. There were even 9mm motors with smaller inserts for 1/4A-1/2a sizes. THey were assembled rather the same way as tandem motors of the period, except it was done by the manufacturer. THey never sold the pieces so you could mix and match.
    Bob Kaplow    NAR # 18L    TRA # "Impeach the TRA BoD"         >>> To reply, remove the TRABoD! <<< Kaplow Klips & Baffle:    http://nira-rocketry.org/LeadingEdge/Phantom4000.pdf www.encompasserve.org/~kaplow_r/ www.nira-rocketry.org www.nar.org
They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety. -- Benjamin Franklin Historical Review of Pennsylvania. 1759
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Bob: and of course all the way back to the early 70's was Semroc's DECAP.....
It just seems to me that if all BP motors were made as -0 and you had a DECAP that could be altered from 1-10 sec....
shockie B)
Bob Kaplow wrote:

somewhat
you now

on machine

then
machine with

inner
charge
to
mid
THe
inserts.
THey
except it

mix
Baffle:    http://nira-rocketry.org/LeadingEdge/Phantom4000.pdf
www.nar.org
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If USR were certified, it would submit a "decap" for Estes D12-0 and C6-0 until the moment of receipt of a cease notice by Estes.
I figure tens of thousands of units could be produced by then.
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:

Boo Hoo.
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Jerry Irvine wrote:

had a

So quit flapping your lips, and comply with the requirements to cert your motors.
Oh wait, you already admitted that you can't comply. Too bad, so sad.
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jerry:
liar liar pants on fire.
I have never contacted any authorities, properly or improperly , except for my own State Fire Marshall,concerning rocketry here in the State of KY....As far as I am aware, rocketry is still as legal and openly pursued here as it ever has.....
well dude if you aren't the poster child for bad behavior in our hobby then I don't know who is... and yeah I seriously considered "outing" you (are you gay too jerry?) to the California State Fire Marshall about your DOT transgressions, but since the NAR could care less, I decided I cared even less.... I am not aware of any other public violations by anybody else in the hobby..... and yes there are some 'behind the scene" machinations that trouble me, but again my opinion is just like an ahole jerry, everybody has one....and I am not the police....if the NAR/TRA brand of "self-regulation" is not working, its not my job nor responsibility to do their job for them.....IF self-regulation actually worked, you would have been run out of the hobby many moons ago......
As usual you are talking poop with no basis in fact.....
the fact that you are trying to smear me here, and not even bothering to answer my questions, just shows you for what you are: a poor pathetic,loser.....and probably a government agent provocateur
shockie B)
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Semroc had such a system in the the '60s with separate delay/ejection trains. Carl recently commented on this in the OldRockets yahoo group. Apparently they had a lot of glue failures that made the system unworkable.
Roy

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roy: yes thats where I first heard of of the Semroc DECAP.. seeems they failed as they were gluing 18mm to 18mm ..butt joined....Carl told me they had a new design with a 13mm tube that would fit in an 18mm ..or an 18mm that would fit in a 24mm ...that would have worked much better and I do beleive thats the route AVI took with their design...
shockie B)

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It just seems to me that EVERYONE getting excited about the RCS (who acquired AT) "adjustable delay times" is new to HP or doesn't fly HP yet!
You want a real delay, use electronics, as that is the "safest" way to go!
I've yet to see anything from CAR/TMT/S&T which buy off on Gary's Press release.... (bunny doesn't make these calls guys.. Just like he deferred to S&T when TMT hit the Kodson stuff a few years back!)
If I were to cert someone for L1 who built their first RMS that day and modified the delay as a part of it, I'd be scared!
Rocksim isn't that accurate with delay times... A big variable is CD which by default, is wrong for larger birds.
I know, from experience, that a motor delay that's 2 seconds over is much less prone to a big failure than one that's 2 seconds early! (error on the long side), and RCS's (formerly AT) announcement is just a "bull in a china shop" move, to backdoor CAR/TMT/S&T! Heck, did you all read the post from CTI that detailed the additional testing involved with their adjustable delay?
Remember +/- 20% folks...

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AZ Woody wrote:

Perhaps -- unless you're new to it, or don't want the cost, or you forget about the extra variables added with wiring, bad batteries, etc.

Sorry, Bunny DOES make these calls. The President is the 'executive' of the organization. He has the OPTION to defer to others for advice, but his call has already been made on this one -- I directly asked the question, his response back was direct -- and furthermore, the statements about 'modifications as recommended by the manufacturer' have been in place for eons.

Me too, unless they explained sufficiently to me the what and why of it (what they did, and why it was needed). Why would this be any 'scarier' than someone using electronics for their level one cert? I have to admit, I kept my level 1 cert 'simple', but simple meant 'standard' - a 3FNC with a piston and parachute.

So? If I launch a bird 2-3 times, and it's consistently deploying the chute 1-2 seconds after apogee, I want to shorten the delay by 1-2 seconds -- it's as simple as that. Rocksim doesn't even (necessarily) come into it.

That's great, I love competition!

Yes, and +/- 20% of 8 seconds might be better than +/- 20% of 10 seconds -- I just don't get why this is so hard to comprehend...
David Erbas-White

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Not quite true, based on real personal experince... The Kosdon Decert specifically. I was a TRA Prefect AND a NAR section advisor at the time.. Bunny refused to get involved, claiming that he defered motor cert issues to S&T. Unless Gary sent him a really nice gift basket last Christmas, I doubt he made this call with anything other than his own personal opinion, and therefore doesn't speak for NAR and S&T!
Why has TRA/NAR/TMT/S&T not yet come out and said "OK.. We agree, and this change does not not require a re-certification!" Not here, ROL, or even the TRA member's list. Gary could post a PR that says anything, (like the Ellis J350 fiasco), but still requires the cert folks to sign off... Oh ya, you're a newbie so you probably don't remember that one!

David.. It's clear that you're a newbie to this stuff, as you just got your L1. As someone that's done many ,many certs and done hours of RSO duty, it's not that hard to determine if a flier is a yahoo. Even a L1 cert flier CAN have experience with electronics. It's also not had to see that someone that finds it manditory to shave a second off an RMS delay doesn't a) grasp that the delay is +/-20% or b) has so little faith in their bird to be able to handle the +/-20% of their bird.
"but I modifed the delay to be 9 seconds, and the bird couldn't handle the stress with 11 seconds! I did everything right!"

This assumes that you always fly the same motor! What if you cert on a H123, and find you can get a H242? This does come into play, as with the 123 and 242, you are dealing with a differnt delay grain, even for "medium". (and in the same case!) The propellaent is different, and therefore, the delay grain is different. A "medium" is not a "medium" for different propellant formulations!

Because, your "8 second ajustment" could be a 6 second delay in reality, and the bird could still be flying mighty fast to result in a good flight! While if you left the delay as it was, you wouldn't shread the chute! Shortening delays is never a good tactic, as I've seen many a bird deploy whle still at top speed!
Again David, you're basing your view on a very limited number of HP flights. (1?). I'm basing mine on years of HP, with and without electronics!
These are the kind of things you SHOULD learn between L1 and L2, but it seems in the last few years, real knowledge isn't a part of the cert process....

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wrote:

It might have something to do with the fact that these people have real lives outside of model rocketry. Besides, it's only been a few days; give them a chance to look it over and respond.
Mario Perdue NAR #22012 Sr. L2 for email drop the planet
http://roci.indyrockets.org "X-ray-Delta-One, this is Mission Control, two-one-five-six, transmission concluded."
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AZ Woody wrote:

Bunny didn't refuse to get involved this time -- he SPECIFICALLY stated that all that would be necessary would be for the manufacturer to endorse the technique. He had the OPTION to not get involved, but that is NOT what he did.
And while he is the President of NAR, as long as he is acting within the 'rules' of the organization, then it is his personal opinion that guides any gray areas -- not that I think this is a gray area, it has been pretty well hashed out that engines can only be modified as the manufacturer recommends.

I'm a newbie to HPR, not to rocketry, and I was around (and paid attention) the Ellis sponge-motor fiasco. If you care to google, you'll have seen me posting here for many years. Here's my take on it -- Aerotech could post a recommendation all day long, but the fact was that the motors were made under entirely different conditions than the ones that were certified -- thus, NAR had the option to pull the certifications due to the fact that they were effectively 'different' motors than the ones that were certified. Now, realistically, this is one that could/did require a judgement call -- Gary could argue that he used the same designs, same formulations, etc., and I wouldn't disagree with a certification organization taking that at face value up until the point where the failures were occurring. Once that happened, all bets were off, and instead of it being somewhat incumbent upon the organization to prove why the motors were 'good', it then switched to being incumbent upon Aerotech to prove the motors weren't 'bad'. My two cents, anyway.

I would venture a guess that I've got more experience with these 'types' of electronics than just about anyone in the hobby today. I'm not talking specifically about rocket altimeters, but very small, low powered data acquisition devices that have to operate off battery power and do different things at different times. And again, though I'm a newbie to HPR, that has been by choice -- and I wouldn't have even done it much at this point (I prefer mid-power myself), except that it required a level 2 to help at NSL, so I decided to get it to help out. I agree that you can determine most folks level of proficiency fairly easily, but even with the fact that I've got mega-experience with these 'types' of electronics, I saw no 'need' to unnecessarily complicate my L1 or L2 certification flights by using it. Remember the KISS principle?
I still disagree with your comments about shaving off a second or two off an RMS delay -- as I've pointed out (ad infinitum, it seems), there are times when 8 +/- 2 seconds is PREFERABLE to 10 +/- 2 seconds -- and making those minor 'tweaks' is part of what this hobby is about. I've also discussed how it would appear that the 'range' of delays available in RMS products is a bit sparse -- you've essentially got a choice of 3 delays that span SEVERAL classes of motors. Going back to the lower-power motors, you have 2,3,4,5,6,7, and 8 second delays, just going from B to E class motors (Estes BP). Why should there be limitation for those doing HPR (or even mid-power)?

Yes, and Gary's chart does exactly that -- it allows you to calculate the depth that must be drilled off of ANY delay they manufacture to get your desired time (within the +/- 20%, of course). I don't know if you read their press release or not, but it DOESN'T say drill 1/32 per second, it tells you how to use the provided chart to find the right depth.

Sorry, that may be your opinion, but I've seen plenty of other experience HPR guys differ with that. And while I (myself) am new to HPR, I've not been ignorant of it -- I've witnessed many flights (obviously, nowhere near as many as you), and have participated in many lively discussions over the years (and have kept my mouth shut in areas where I don't know what I'm talking about, but still read the comments by others).
Again, all else being equal, if I have a rocket that consistently is deploying on the way down, where everything I've got TELLS me that is going to happen (be it Rocksim, timing the rocket each time, experience of others, etc.) then it would seem just common sense to shorten the delay as needed. Again, taking your example into account, I would 'tend' to pick a delay where if it happened to be on the short side, it wouldn't be too long before apogee, but that is part of what this hobby is about -- doing those kinds of changes and gauging the effects -- trying to get that 'perfect' flight.

I don't dispute that I've got a lot to learn in the HP realm, and that experience is the best teacher. That having been said, I can't think of a single thing that could have been done better on either my level 1 or level 2 certification flights -- and I think those who signed off on them would agree. I'm not particularly modest, and think I'm a damn fast learner -- but I'm also not particularly a 'newbie', either -- even if HPR is 'new' to me.
David Erbas-White

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