Crash site locator beacon

The Locator Beacon (LB) is an 18 inch diameter hemispherical unit designed to be air dropped via parachute from a search aircraft near an aircraft crash site. The LB is self uprighting when it lands on the ground and its antenna is always oriented for maximum efficiency. When activated, the LB sends out a radio frequency signal on 121.6 Mhz and 243.2 Mhz, this signal can be tracked by aircraft or by ground parties equipped with directional locating equipment. The LB also contains a strobe light beacon to aid in visual acquisition of the unit. The LB remains in the active (broadcast) mode for approximately 20 minutes before resetting itself to the listening mode. External VHF activation of the LB repeats the LB broadcast and strobe light cycle for another 20 minutes.