Mobile Aeronautics Education Laboratory

ELT Search Simulation

This search simulation emulates the function of a commonly used instrument, the DF88. This is a direction finder used to locate the site of a crashed plane which has an operational Emergency Locator Transmitter (ELT). The DF88.EXE software program is a simulation that allows you to "fly" around a hypothetical map looking for the source of the ELT using a simulated DF88 instrument display. Once you think you have found the crash site, you can request the actual location and then find out how far off you were. Below is a sample screen from the program:

DF88 Sample Screen The ELT has been revealed at the end of a search on this screen. You can see the red search aircraft just below it. The cross hairs indicate the actual location of the ELT. The instruments along the right side show the heading of the aircraft, how far it has travelled, and the DF unit showing the direction of the signal. There is also a working VOR station and panel indicator, although not needed for the search, it was added as an additional instruction piece.

It should be noted that only about 1% of all ELT searches are for actual aircraft crashes. The other 99% are due to inadvertent activation of the ELT. The majority of the searches conducted in the U.S. are performed by the Civil Air Patrol.

Ground ELT Practice Search

Ground Search Photo

Locating an ELT sometimes requires ground personnel as well. Here, two members of the Civil Air Patrol are using a hand held ELT direction finding unit to locate a hidden ELT training transmitter at the airport.

Click here to hear the sound of the ELT being heard in their receiver.


Search and Rescue Activities
Download a copy of DF88
Back to the GPS/Amateur Radio Workstation Home Page
NASA/Glenn Research Center
Educational Programs Officer: R. Lynn Bondurant
Curator: Bruce Bream {bruce.bream@grc.nasa.gov}
Last Update: 6-Jan-97