Module 6 of CASARA ELT Training Plan Aircraft ELT Homings Module 6 of CASARA ELT Training Plan

High wing aircraft with dual belly mounted antennas

Low wing Aircraft with dual belly mounted antennas

ELT Triangulation Similar to ground and vehicle ELT homing, another method to determine the ELT signal source is Triangulation. First fly toward the ELT signal source until the receive signal level peaks, and then drops off. Second mark your track on the map or record your track on the GPS. Fly past the signal peak by two miles, turn right 120 degrees and fly for 2 miles. Then turn right toward the signal and fly until you are an estimated 2 miles past the signal peak. Then turn right 120 degrees and fly for 2 miles. Then turn right toward the signal and fly until you are past the signal. What you have flown is very similar to a 3 leg Sector Search pattern. The intersection of your 3 tracks will be the location of the signal source. All Left turns will also work.

ELT Triangulation Line 1 Line 2 Line 3

Keep connections to a minimum as connections are sources of trouble.

Strut mounted testing conducted in Sask MO.

What is a Null?

Dead spot directly above the end of the antenna As pointed out in the Radio Basics module there is a dead spot at the end of the antenna. If the antenna is vertical this will be when directly above the antenna / ELT. Therefore if you fly directly over the antenna you will see a marked drop in signal strength for a couple seconds. One caution with this is that should the ELT antenna not be in the vertical position, but at an angle, then the cone of silence will also be slanted.