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- Newsgroups: rec.models.rockets
- Path: sparky!uunet!paladin.american.edu!howland.reston.ans.net!sol.ctr.columbia.edu!The-Star.honeywell.com!umn.edu!vx.cis.umn.edu!soc1070
- From: soc1070
- Subject: Re: Tracking
- Message-ID: <25JAN199313112698@vx.cis.umn.edu>
- News-Software: VAX/VMS VNEWS 1.41
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- Nntp-Posting-Host: vx.cis.umn.edu
- Organization: University of Minnesota CIS
- References: <1993Jan25.163448.20293@aio.jsc.nasa.gov>
- Date: Mon, 25 Jan 1993 18:11:00 GMT
- Lines: 43
-
- 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.
- >
- >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 :)
- >
- > Tom E. Smith
-
- Alot of people use carpenters chalk or powdered tempra paint (I like
- tempra better, the colors are cooler :) ), but usually only to get
- a reference at ejection. I don't know if anyone's ever devised a 'spill'
- method, to release it over time.
-
- I imagine it could be done something like this:
- Take a tube maller than the main body of the rocket and fill it with
- chalk/tempra. Constrict it somehow on the gravity down end an cap it.
- Have the ejection charge rigged to release the cap, and then the chalk
- flows out like sand from an hourglass. The downside is that you'd
- probably have to dump A LOT of chalk to track it this way. A smoke
- capsule would probably work better and weigh less.
-
- 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.
-
- ------
- Tim Harincar A skunk is better company than
- soc1070@vx.cis.umn.edu someone who prides themselves on
- being frank. -Lazerus Long
-