From: Roger.Wilfong@umich.edu  (Roger Wilfong)
Newsgroups: rec.models.rockets
Subject: Re: Igniters
Date: Fri, 22 Jan 1993  09:52 edt
Organization: UofM Hospitals
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In Article <634@rml.UUCP> "jack@rml.UUCP (jack hagerty)" says:
> In article <1993Jan21.010654.3022@hpcvaac.cv.hp.com> billn@hpcvaac.cv.hp.com (bill nelson) writes:
> >Roger.Wilfong@umich.edu (Roger Wilfong) writes:
> 
>  [talking about AmSpam "ignitor" article]
> 
> >: It was the lack of that information that disapointed me.
> >
> >Agreed - the research was very poorly conducted. The person also did not
> >seem to know too much about thermodynamics. I would have been interested
> >in the energy output curves.
> >
> >It would also have been nice if the person had done some testing of just
> >how fragile the various igniters were.
> >
> >All in all, I found the articles rather useless.
> 
> I think you guys have both picked up on my main complaint about Douglas
> Kirk, M.S., Directory of the Model Rocket Test Facility (tm) that I
> moaned about in my tirade a couple of weeks ago. (Said tirade, BTW, was
> almost universally ingnored by this group. Whatsa matter, can't be
> bothered by such small fry?)
 
I didn't ignore it, I threw fuel on the fire (sorry, make that flammable 
solids - if reloads are as fire proof as this group has been, DOT shouldn't 
be concerned).
 
As a follow-up to my comment of the MRTF's product testing requirements.  I 
talked with the local manufacturer who was put off by the MRTF's 
requirements and got real numbers.  
 
As a requirement for testing a company's products, the company must supply 
five (5) of each kit to be tested, plus motors, plus a launch pad, plus a 
launch controller.  Five of each kit - that is as more than most hobby shop 
orders.
  
> Mr. Kirk apparently conducted his "research" based not on any study to
> determine what parameters made an ignitor work, but rather on what tests
> he was able to perform. 
 
 
> Why did he vary the voltage and not the current? Because he could! Why didn't 
> he vary the current? 
 
Well.  Varying the voltage is a way to vary the current.  But if you don't 
measure the current, it's lost.
 
> Does dipping an ignitor in plastic 
> and firing it under water determine how well it can ignite a rocket motor?
 
Don't you dip your rockets in plastic and launch them from under water?  
You're missing out on valuable mission point on that scale Trident.  :-)
> I don't know, but it was a good test!
> 
> The thing that still gnaws at me is that this guy is passing himself off
> as an athority, and his "research" will probably be taken as gospel by
> the Grammar/High School age crowd which is still the main target of the
> NAR educational programs.  When I saw the first installment, I was hoping
> for an article like Matt Steele's excellent study of black powder CATO's
> a few issues back. But when I saw the name at the top (and on all the 
> captions, and tables, and sidebars) I just groaned.
 
I have to agree with you.  Albeit uncomfortably.  I really don't like to 
complain about others contributions to the magazine, when I haven't made 
any contributions.  Shoot Peter keeps bugging me to write up my "TwOnyx" and 
camera payload for T-minus-5.
 
BTW, I don't have an MS.  Just a BS - or is that what I'm full of - I can 
never keep that straight.
 
-Roger