[MilCom] ELT Alert Beacons Can Hobbyists Help In Reporting Quicker?

Ken rfinder1 at verizon.net
Thu Aug 9 21:30:46 EDT 2007


Are scanner radio hobbyists in the position to help in more quickly
resolving these situations?

Interestingly, my understanding is that 95% of all Emergency Locator
Transmitter activations are false primarily due to electronic/battery
problems.

As many of you know Civil Air Patrol  http://www.cap.gov/  is tasked with
locating these beacons.  All of the beacons (including the new PLB's)
transmit a homing signal/sound on 121.5 mhz and may sound like this
http://www.grc.nasa.gov/WWW/MAEL/ag/elt.wav BUT if the batteries are low, no
tone may be transmitted, only a carrier.   Unfortunately, when the SARSAT
satellite hear's the transmission it doesn't know if it is a malfunctioning
unit or a real problem.  Info on sarsat can be found at:
http://www.sarsat.noaa.gov/  &
 http://en.wikipedia.org/wiki/Emergency_Position-Indicating_Radio_Beacon

Civil Air Patrol uses specialized direction finding equipment in aircraft,
vehicles, & portable operations see: http://www.ltronics.com/   &
http://level2.cap.gov/documents/u_081503135122.pdf  for more information

Sometimes if you monitor CAP's VHF FM/P25 radio network you may hear them
coordinating trying to find these ELT beacons with air, mobile, & portable
units.  It's been rumored that CAP may also use cellphones in some areas
rather than their radio network in tracking down ELT's to include
sprint/nextel nationwide walkie talkie and off network functions.

The system does have some alert lag time in it with the older ELT units.
First and foremost, the SARSAT satellite might have to make more than one
pass before the Air Force Rescue Coordination Center actually sends an alert
out to CAP.  My understanding is that this may take anywhere from 3 to 5
hours.   CAP units will than be sent out on an authorized AF mission to find
the ELT beacon.  The goal is to identify the source & silence all false
beacons as soon as practical to ensure that if there's a real emergency the
satellite will pickup the actual distress signal.

So perhaps all monitoring hobbyists could provide some assistance in
alerting authorities and assisting with ELT beacons being found more
quickly.  Just place 121.5 mhz into your mobile, portable, and/or base
station scanning sequence and if you pickup an alert beacon signal contact
your nearest airport control tower, flight service station, air route
traffic control center watch officer, etc.. and provide them with you exact
location.  My understanding is that if you call CAP directly they will have
to get authorization from higher headquarters & the USAF before actually
dispatch UDF teams.

BTW Civil Air Patrol is always looking for technically inclined potential
members both seniors and cadets.  Urban Direction Finding Team training
(see:  http://level2.cap.gov/documents/u_052704140516.pdf  may be provided
to all members that are interested.  Local CAP units can be found at the
website:   http://cap.findlocation.com/

Ken




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