HDTenEightyP/NetNews huggingface dataset:
From: jason@ab20.larc.nasa.gov (Jason Austin)
Newsgroups: rec.models.rockets
Subject: Re: Tracking
Date: 26 Jan 93 15:25:21
Organization: NASA Langley Research Center, Hampton, VA
Reply-To: Jason C. Austin <j.c.austin@larc.nasa.gov>
NNTP-Posting-Host: ab20.larc.nasa.gov
In-reply-to: tes@motif.uucp's message of Mon, 25 Jan 1993 16:34:48 GMT

In article <1993Jan25.163448.20293@aio.jsc.nasa.gov> tes@motif.uucp (Thomas E. Smith) writes:
-> 
-> Something that I didn't see in the FAQ was tips on tracking a medium to high
-> power rocket once it flies out of visual range. I _had_ a rocket that soared
-> very nicely up to around 3200ft. It was a windy day, so I put a siren in the
-> rocket and launched it about 70 degrees from the horizon into the wind. I saw
-> the chute open :) and proceeded to make a BIG mistake: look down as I walked
-> towards it. I could have kept track of it if I hadn't taken my eyes off it, so
-> it was history :( . I spent a couple of hours looking for it. The siren is
-> probably only audible if you're close enough to see it.
-> 
-> The question is, is there some type of smoke or colored chalk dust you can
-> use to make the rocket more visible as it comes down? If so what type of 
-> mechanism (commercial or home-made) do you use to steadily release the smoke or
-> chalk? And what other methods could be used? This is the main issue keeping me
-> from tackling high-power rocketry where I plan on breaking 3200 ft.

	I once saw a device at a hobby shop to help with this problem.
You put a small transmitter in the rocket and keep a gun shaped
detector on the ground.  The gun beeps louder depending on how how
directly you're pointing it at the transmitter.  I think that set was
around $30.  I don't remember what kind of range they claimed.

-> BTW, does anyone know the decent rate of a 1lb rocket with an 18" chute? I
-> guessed that it took about 90 seconds for the rocket to land with the chute.
-> With about a 25 mph wind that puts the rocket at (25mph * (90s/(3600 sec/hr)))
-> .625 mi from where I launched it. So that was where I concentrated the search.
-> 
-> Thanks in advance for any help :)

	I believe this will vary greatly depending on the shape of the
rocket and the parachute.
--
Jason C. Austin
j.c.austin@larc.nasa.gov

Newsgroups: rec.models.rockets
From: 161685732@vill.edu (JOE PRYSZLAK)
Subject: Powr Pad
News-Software: VAX/VMS VNEWS 1.4-b1  
Organization: Villanova University
Date: Mon, 25 Jan 1993 04:18:00 GMT

In my ever vigilant (sp?) attempt at getting my old Powr Pad in prime
condition, I'm still looking for two other pieces:

Still in pursuit of the infamous angled blast deflector that it used to
come with (Quest used the same deflector in it's first year of operation, so
if anyone has an old angled Quest deflector they're willing to part with,
lemme know.)

I also need the lauch key, the big momma made of red plastic that showed the
rocket launching on it.  If anyone has one, lemme know...

Thanks in advance...
From: Roger.Wilfong@umich.edu (Roger Wilfong)
Newsgroups: rec.models.rockets
Subject: Re: Tracking
Date: 26 Jan 93 20:36:00 GMT
Organization: UofM Hospitals
NNTP-Posting-Host: robin.hosp.med.umich.edu
X-Newsreader: FTPNuz (DOS) v1.0

In Article <1993Jan26.200215.12845@hpcvaac.cv.hp.com> "billn@hpcvaac.cv.hp.com (bill nelson)" says:
> soc1070 writes:
> : In article <1993Jan26.011603.22455@hpcvaac.cv.hp.com>, billn@hpcvaac.cv.hp.com (bill nelson) writes...
> : >: 
> : >: As for decent rates, I think a basic problem would be that two
> : >: different rockets, each exactly the same weight and with the 
> : >: same size 'chutes, would fall at different rates, because the one
> : >: with the larger exposed area (i.e. fins, tube, etc) would be carried
> : >: further down wind. A one pound rocket and a one pound sphere with 
> : >: identical chutes will not likely fall in the same place, so its
> : >: difficult to say. In your case, what you computed was the *closest*
> : >: possible distance.
> : > 
> : >This is a little misleading. They will both fall at the same rate.
> : >They will not fall at the same descent angle - the one with the greater
> : >lateral area of resistance will drift further.
> : > 
> : 
> : You are correct. When I first posted that, I started to type that the
> : decent rates would be the same, then I confused myself and thought the
> : rates would be different. Must be work-related stress :)
> : 
> : The decent rate is constant, the speed of the model relative to the
> : ground changes.
> 
> Actually, my response is also incorrect. Given a constant wind velocity,
> the speed relative to the ground will also be identical - regardless of
> the respective lateral wind resistance of the objects.
> 
> : There are also other factors: thermals, sinks, gusts, wind direction
> : changes, etc. All will effect the landing point of a model. I once thought
> : of writing a computer program to figure the landing area of a model,
> : but there are just too many variables changing too fast (or unmeasurable).
> 
> When the velocity changes rapidly, then the velocity over the ground will
> not be identical. Constant thermals and sinks will not affect ground speed.
> 
 
Of course, what were really interested in is how far down range the rocket 
lands.  That 'B' egglofter I chased for 1.5 hours was only moving at 4 or 5 
miles ground speed (same as the 1/2A streamer I'd chased earlier) but I have 
no idea how far away it landed - I gave up when it disappeared as a tiny dot 
over head - I don't think an X-form would have made any difference in that 
thermal :-)
 
-Roger
Newsgroups: rec.models.rockets
From: billn@hpcvaac.cv.hp.com (bill nelson)
Subject: Re: Shred Avoidance
Organization: Hewlett-Packard Company, Corvallis, Oregon USA
Date: Wed, 27 Jan 1993 23:35:19 GMT

jackson@sn.jsc.nasa.gov writes:
: >
: >If you want a hot motor - get a Teeling Technologies K-2300. That's
: >right - over twice the average impulse of the notorious K-1100 rocket
: >shredders. Or, how about a J-700 or a K-500? All these would do a
: >good job of seriously stress testing your pet rocket.
: >
: Ok, now what the diddly is a 'Teeling Technologies' motor,
: saw this listed in HPR for the Octoberfest meet.

They are custom manufactured motors. I do not know if they are Tripoli
approved, or not. I suspect there are a lot of motors used at LDRS that
are prototypes or unapproved - I may be wrong.

: What is a Urinsco motor? 
: Gumby motor?

I don't know anything about Urinsco motors. Nobody seems to know who
"Gumby" is - apparently the motors are pretty good.

: ...and I figure U.S. Rocket motors are defunct.

I suspect that Jerry, for some idiotic reason known only to himself,
has decided that HPR rocketry is not the place to do business. No big
loss - I liked the engines, but he was very slow in filling orders or
refunding money for defective products.

: >: For airframe I use only Phenolic and Fiberglass
: >: and am testing the new carbon fiber composites.
: >
: >I think I am going to quit using phenolic - it is too brittle. I have
: >found that a slight crack or scratch produces a serious weak point. I
: >will stick to fiberglass or possibly carbon fiber construction.
: >
:  Yeah I know. I dont have any trouble with Phenolic as long as I am
: flying on grass or soft ground. I have found phenolic fairly easy to
: repair as long as its not a long twisted break.
: The new cabon fiber reinforced stuff looks like it solves the brittle
: phenolic problem. To bad its so expensive right now.

Apparently one manufacturer of rocket kits (Dangerous Dave?), sells the
carbon fiber stuff for only a slight premium over fiberglass.

Bill

Newsgroups: rec.models.rockets
From: rbs@cyclops.micr.Virginia.EDU (Robert B. Sisk)
Subject: Re: Payloads
Organization: University of Virginia
Distribution: usa
Date: Mon, 25 Jan 1993 13:43:44 GMT

In article <1993Jan22.230809.15912@cbfsb.cb.att.com> hrbob@ixstar.ih.att.com (R.E. Wiersbe) writes:


STUFF DELETED



>
>Okay, I'm on sunsite....there's the RMRFAQ directory (with files)....hmmm...
>the articles and plans directories are empty!!!! Can't create a POSTS directory..
>getting rmrfaq.1.2....yep, it worked!!!
>
>So what happened to the stuff in the articles and plans directories????!!!????

The old stuff in these directories was corrupted!  So it has been removed.
Actually I do not think anything has ever been uploaded for the plans
directory.

>
>I'm going to put a file into the uploads/rockets directory now.....it worked!!
>

I could not find anything uploaded to the uploads/rockets directory.  This
has been the problem with SunSite in the past.  People have not been able
to upload files.

>So how do I create a POSTS directory to put the posts for the last year into
>the archives??? The files are waiting!!

You can not create a directory in the uploads/rockets directory.  This is one
of the archive managers rules (not mine).  All files have to be uploaded to
the uploads section then moved to their appropriate site on the archive.  I
am just the person who moves the files.  Thus, it is very important that a
message be sent to me when someone uploads a file.  I only check for uploads
every couple of weeks.  Please send the files and I will move them to a
POSTS directory in the r.m.r archive.  Since I know you have a lot of files
send one or two and let me check that they are really finding their way
onto the site in good shape.  If they are I will send you an email message
that its OK to send the rest.  

Thanks

Bob


-- 
---------------------------------------------------------------------------
Robert B. Sisk  PhD			Internet: rbs@virginia.edu
NAR #53448				UUCP:     uunet!virginia!rbs
TRIPOLI #1583                           CIS:      71501.1651@CompuServe.COM
Newsgroups: rec.models.rockets
From: jsvrc@rc.rit.edu (J A Stephen Viggiano)
Subject: Re: Igniters
Organization: RIT Research Corp
Distribution: na
Date: Thu, 28 Jan 1993 01:55:39 GMT

In article <C1JF2o.Lv3@usenet.ucs.indiana.edu> ntaib@silver.ucs.indiana.edu (Iskandar Taib) writes:

>Well, actually, I think its a good idea, *provided* he measures
>the actual voltage drop across the ignitor, or uses a current source
>with very little internal resistance. Current is dependent only on 
>the voltage drop and the resistance of the ignitor, and the latter
>value can easily be determined and shouldn't vary from sample to 
>sample.

Well, yes and no. The rub is that the resistance of the igniter will change as
it heats up. Try measuring the resistance of a 60 Watt lightbulb, then go
through the calculations. What!?! You didn't get 240 ohms when you measured it
with your nice digital multimeter? It will have a resistance of 240 ohms when
you pass half an ampere of current through it, instead of the few scant
milliamps you'll use with your multimeter.
Newsgroups: rec.models.rockets
From: ntaib@silver.ucs.indiana.edu (Iskandar Taib)
Subject: Re: Tracking
Organization: Indiana University
Date: Thu, 28 Jan 1993 00:49:10 GMT

In article <1993Jan25.163448.20293@aio.jsc.nasa.gov> tes@motif.uucp (Thomas E. Smith) writes:

>The question is, is there some type of smoke or colored chalk dust you can
>use to make the rocket more visible as it comes down? If so what type of 
>mechanism (commercial or home-made) do you use to steadily release the smoke or
>chalk? And what other methods could be used? This is the main issue keeping me
>from tackling high-power rocketry where I plan on breaking 3200 ft.

Or even better smoke that is released after the rocket hits the 
ground. 9-)

Actually, the free flight people have a variety of devices for 
airplane retrieval, all the way up to onboard transmitters and 
receivers with directional antennas.




-- 
-------------------------------------------------------------------------------
Iskandar Taib                          | The only thing worse than Peach ala
Internet: NTAIB@SILVER.UCS.INDIANA.EDU |    Frog is Frog ala Peach
Bitnet:   NTAIB@IUBACS                 !
Newsgroups: rec.models.rockets
From: hrbob@ixstar.ih.att.com (R.E. Wiersbe)
Subject: Re: Question about electronic ejection control
Originator: news@cbnewsb.cb.att.com
Organization: AT&T Bell Laboratories
Distribution: usa
Date: Fri, 22 Jan 1993 22:55:22 GMT

In article <1993Jan22.172703.15050@rsd0.rsd.dl.nec.com> buzz@rsd.dl.nec.com (Buzz McDermott) writes:
>I would like to build an electronic ejection control system into my next
>rocket.  I want the ability to set varying ejection delays based on
>different motors and vehicle weights.
>
>I've seen mention of and advertisements for electronic timers that may be used
>to control custom ejection delays.  I understand that these are hooked to 
>a capacitor or battery as a source of power for an electric match or 
>flashbulb.   What gets fuzzy after that is exactly what is used to provide
>the ejection change itself.  Do you use black powder in some type of container,
>which you ignite via the pulse from the capacitor/timer?
>
>I'm interested in construction details, parts requirments, sources for the 
>black powder, alternatives to explosive ejection systems (if any), etc.
>
>Have there been any construction articles in _Tripolitan/HPM_ or _AmSpam_?
>
>Are there commercial products available?
>
>Any and all help is greatly appreciated.
>
>================================================================================
>= Buzz McDermott                Disclaimer: I speak for no one but myself, and =
>= buzz@rsd.dl.nec.com                       anyone who listens to anything I   =
>= NAR   13559                               have to say deserves whatever they =
>= TRA    1785                               get!!                              =
>================================================================================

Robbie's Rockets makes ejection charges in various sizes for different diameter
rockets. Basically, it's a flashbulb and black powder in a tube. They should be
listed in the Manufacturers listing from Mike Jungclas. If not, I'll look for
the catalog I have. (They were giving out free samples at Danville last year, I
got one of the smaller ones, but haven't used it yet.)

The flashbulb gets ignited by whatever electrical device you supply (timer board,
switch, etc.). Most of the electronic timers use a 9V battery. I would suggest
getting an Adept and Robbie's Rockets catalog. 

Bob Wiersbe	hrbob@ihlpb.att.com	NAR# 44588
From: barrett@add.itg.ti.com
Newsgroups: rec.models.rockets
Subject: Re: Igniters
Date: 21 Jan 93 16:58:41 GMT
Organization: Texas Instruments Incorporated, Austin
NNTP-Posting-Host: powder.add.itg.ti.com

In article <1993Jan21.142728.16273@aio.jsc.nasa.gov>,
        jackson@sn.jsc.nasa.gov writes:

>>I have had a problem with Aerotech RMS G motor loads and chuffing.

  Al, I have had some similar problems, especially with the G25.  What I
have started to do is drop a short piece ot themalite in the motor and
then insert the Copperhead.  The copperhead will keep the piece of
thermalite in place at the top of the motor.  This requires that you
insert both with the motor in the nozzel up orientation ;-)

Stu Barrett  barrett@add.itg.ti.com
TRA#1277  NAR#4341
From: barrett@add.itg.ti.com
Newsgroups: rec.models.rockets
Subject: Wanted: ISP/RMS 38/360 casing
Date: 25 Jan 1993 16:47:30 GMT
Organization: Texas Instruments Incorporated, Austin
NNTP-Posting-Host: powder.add.itg.ti.com

  Always the optimist, I'm looking for a ISP/RMS 38/360 casing.  Anyone
know of an ISP distributor that still has any RMS hardware left?

  Anyone want to part with their own?  I'll buy a complete set if
needed.

Stu Barrett  barrett@add.itg.ti.com
TRA#1277  NAR#4341
Newsgroups: rec.models.rockets
From: tes@motif.uucp (Thomas E. Smith)
Subject: Tracking
Organization: Software Technology Branch, NASA/Johnson Space Center
Date: Mon, 25 Jan 1993 16:34:48 GMT

Something that I didn't see in the FAQ was tips on tracking a medium to high
power rocket once it flies out of visual range. I _had_ a rocket that soared
very nicely up to around 3200ft. It was a windy day, so I put a siren in the
rocket and launched it about 70 degrees from the horizon into the wind. I saw
the chute open :) and proceeded to make a BIG mistake: look down as I walked
towards it. I could have kept track of it if I hadn't taken my eyes off it, so
it was history :( . I spent a couple of hours looking for it. The siren is
probably only audible if you're close enough to see it.

The question is, is there some type of smoke or colored chalk dust you can
use to make the rocket more visible as it comes down? If so what type of 
mechanism (commercial or home-made) do you use to steadily release the smoke or
chalk? And what other methods could be used? This is the main issue keeping me
from tackling high-power rocketry where I plan on breaking 3200 ft.

BTW, does anyone know the decent rate of a 1lb rocket with an 18" chute? I
guessed that it took about 90 seconds for the rocket to land with the chute.
With about a 25 mph wind that puts the rocket at (25mph * (90s/(3600 sec/hr)))
.625 mi from where I launched it. So that was where I concentrated the search.

Thanks in advance for any help :)


-- 
____________________________________________________________________________
| It's not my damn planet, understand  | Tom E. Smith                      |
| Monkey Boy?!!       John Bigbootey   | tes@gothamcity.jsc.nasa.gov       |
----------------------------------------------------------------------------
From: Roger.Wilfong@umich.edu  (Roger Wilfong)
Newsgroups: rec.models.rockets
Subject: Re: Igniters
Date: Thu, 21 Jan 1993  07:34 edt
Organization: UofM Hospitals
Distribution: world
NNTP-Posting-Host: robin.hosp.med.umich.edu
X-Newsreader: FTPNuz (DOS) v1.0

In Article <1993Jan21.010654.3022@hpcvaac.cv.hp.com> "billn@hpcvaac.cv.hp.com (bill nelson)" says:
> Roger.Wilfong@umich.edu (Roger Wilfong) writes:
> : > 
> : > The voltage is immaterial - as long as the current is high enough. I have not
> : > run across any launchers where a 12 volt battery was not sufficient, even 
> : > using 22 gauge wire. 
> : > 
> :  
> : Generally, as the voltage is increased, the current increases.  This of 
> : course assumes that every thing else is equal - which it isn't.  You need to 
> : account for the total resistance of the circuit including the resistance of 
> : the source, wire, connectors and load.  However, there is some amount of 
> : current [ actually, power I*I/R(ignitor) ] that when applied for a given 
> : length of time will initiate an ignitor.  There is also presumably a 
> : threshold current below which each type of ignitor will not fire.
> :  
> : 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.
> 
 
Yup.
 
> Most people would not be interested in the threshhold firing levels,
 
I disagree.  If you are thinking of designing your own 'flash bulb safe' 
controller, this information is critical.  I have never seen these values 
authoratively documented.  'Flash bulb safe' is always assumed to be just 
'a few milliamps'.
 
> where
> it might take 10 seconds for the ignitor to start burning. What most of
> the people would want to know is the current that will guarantee ignition.
 
I agree this is also important, it dictates the power source and the 
allowable resistance in the wiring.
> They would also like to know if there is a current that is too high. It
> is not too likely, with the systems we use, but is possible with one of the  
> capacitive discharge systems that are used for some squibs and blasting 
> caps.
 
Interesting information, but I agree it's not too likely our systems will 
supply too much current.
 
> 
> It would also have been nice if the person had done some testing of just
> how fragile the various igniters were.
 
Yup.
> 
> All in all, I found the articles rather useless.
  
Ditto.
- Roger
From: kw0426@shire.ac.arknet.edu
Newsgroups: rec.models.rockets
Subject: rocketry software
Date: 25 Jan 1993 23:29:36 -0600
Organization: UTexas Mail-to-News Gateway
NNTP-Posting-Host: cs.utexas.edu

Hello!
This is:  kw0426@shire.ac.arknet.edu
Does anyone out there have software available (ftp perhaps..) for
predictions of a model rockets performance.  Perhaps a design aid.
I'm interested in anything like this, especially source code (C..)
that I can recompile on VAX/VMS, or possibly on a Mac Quadra.
If you have software available, or know where I could look for it,
please contact me through email.
Thank you for your time--
-- kw0426@shire.ac.arknet.edu
Newsgroups: rec.models.rockets
From: billn@hpcvaac.cv.hp.com (bill nelson)
Subject: Re: Tracking
Organization: Hewlett-Packard Company, Corvallis, Oregon USA
Date: Wed, 27 Jan 1993 00:22:54 GMT

jason@ab20.larc.nasa.gov (Jason Austin) writes:

: 	I once saw a device at a hobby shop to help with this problem.
: You put a small transmitter in the rocket and keep a gun shaped
: detector on the ground.  The gun beeps louder depending on how how
: directly you're pointing it at the transmitter.  I think that set was
: around $30.  I don't remember what kind of range they claimed.

That is an audio tracker - it is only good for a few hundred feet. I seem
to recall that Estes says 100 feet, but am not sure.  It is overpriced.
You can buy a buzzer and battery for a few dollars for the "transmitter".
You can use a plastic funnel, costing another couple of dollars, for the
"receiver". Not elegant, but just as good. It is useless for "out of sight"
rockets.

: -> BTW, does anyone know the decent rate of a 1lb rocket with an 18" chute? I
: -> guessed that it took about 90 seconds for the rocket to land with the chute.
: -> With about a 25 mph wind that puts the rocket at (25mph * (90s/(3600 sec/hr)))
: -> .625 mi from where I launched it. So that was where I concentrated the search.
: -> 
: -> Thanks in advance for any help :)
: 
: 	I believe this will vary greatly depending on the shape of the
: rocket and the parachute.

It would depend most on the drag coefficient of the chute. There are
equations for calculating the rate. I think there was an article in
the Tripolitan (High Power Rocketry Magazine). There is also a book
that was written by a rocketeer covering the subject. I do not recall
the title or who has it for sale. Maybe someone else will remember.

The shape of the rocket has nothing to do with the descent rate. It
has negligible lift at descent rates.

Bill
From: billn@hpcvaac.cv.hp.com (bill nelson)
Newsgroups: rec.models.rockets
Subject: Re: Igniters
Date: 26 Jan 93 14:57:48 GMT
Article-I.D.: hpcvaac.1993Jan26.145748.3731
Organization: Hewlett-Packard Company, Corvallis, Oregon USA

jack@rml.UUCP (jack hagerty) writes:
: 
: >Anything of any use in the articles, you could easily obtain by making a
: >5 minute phone call to the manufacturer.
: 
: Ah, but how impartial would *they* be :^)

If the articles had contained anything useful, then I would agree. However, we
have to judge by what was there - I saw nothing that a manufacturer would not
have been willing to supply. 

Note that the voltage applied tells us very little. We don't even know if
that is sufficient voltage drop, across the ignitor, to cause it to ignite.
All we know is that this is a minimum value - practical values are likely
to be higher. How much, we cannot determine, because he did not tell us about
his test setup.

Now, this problem could have been eliminated very simply. All he would have
had to do was measure the circuit current. Then, it does not matter how the 
resistances of the circuit may be distributed. You know that, if a certain
current flows, then the ignitor will function.

Also, testing for 'eventual' ignition is also not very useful. I have not
read the 1192 rewrite recently, but the proposed NFPA 1197 for High Power
Rocketry mentions that liftoff will occur within 3 seconds after applying
power to the ignitor. As such, a more realistic test would be that the
ignitor provided its maximum energy output within one second of current
application. 

Bill