Model Forum / General / Rockets / August 2004

I can get a very loud compact magnetic siren for about $1.50 each, it uses 3
watch cells. You can hear these a long distance away.

There's also the beepers from Transolve:

   http://www.magnumrockets.com/transub.html
   http://www.magnumrockets.com/transtb.jpg

I've used the trans-beep several times.  It works very well, although it
tends to make the rocket get hung way up in a tree near the flightline so
that everyone can hear the beeper the rest of the day  :-)

-- David

I have very successfully used the panic alarm type - cant remember the name
but paul sells them on www.traxa.co.uk

Audible from apogee on a 4" rocket on a J400 (cant remember altitude),
audible all the way on a several-hundred yard recovery walk, even after the
rocket landed in thick corn, beeper at ground level. Only thing is 2" tube
is the smallest they will fit in unmodified, I think 38mm or perhaps BT-55
could be done with the casing off. Runs off a GP23A 12v 'lighter battery'.

I would suggest that where possible the pull cord is pulled before launch,
since then there's no guessing - you will have a beeper at ejection. However
this may depend on pad times etc.

Niall

Phil,

Adept Rocketry has a whole menu of different sized beepers.  See
http://www.adeptrocketry.com/beepers.htm

I have never used one of theirs, but saw them the other day when I was at
their site looking up something else.  It looks like their biggest model is
an absolute screamer.

My $0.02: At Argonia we contend with mostly wheat and milo and on occasion
soybeans.  The most successful recoveries on high-altitude flights are using
radio tracking (Walston, Rocket Hunter, Adept, etc.).  I'm not a
high-altitude flyer so I usually see where the rocket lands, I just have to
contend with finding it in the standing crops.  I have used Radio Shack
alarms and small personal alarms bought off internet auctions for ~$5 in
bigger rockets under these conditions.  If I crash, I don't lose much.  I've
used my Pratt beeper in smaller rockets; I haven't had it long enough to be
able to compare it with the other types.  With the beepers, once you get
close you can usually hear them.  It is a little amazing, though, how
sometimes when the rocket is laying down amongst the plants how little the
sound really travels.

You probably know this and I don't know if it fits the context of what
you're writing, but it is pertinent.  An important factor to consider is
also rocket and parachute color.  You have to step on a green and yellow or
brown rocket and/or parachute to find it.  Hot pink parachutes are easy to
spot; there's nothing in nature that is hot pink.  It is not uncommon for a
parachute to nestle down between crop rows rather than lay on top.  I have
seen people use really long mylar streamers to help spot the rockets.  Helps
in the air and on the ground.

This is definitely a worthwhile subject to share with inexperienced flyers.

--Lance.

Thanks to everyone for their input.

Here is what I came up with.

http://www.para520.org/docs/sonic_rocket_locators.htm