Final answer:
The 406 MHz Emergency Locator Transmitter (ELT) system aids in aircraft search and rescue through components that include an antenna, internal electronics, GPS, housing, a transmitter, and control mechanisms. It operates on a frequency monitored globally by search and rescue satellites, chosen due to low absorption by building materials.
Step-by-step explanation:
The 406 MHz Emergency Locator Transmitter (ELT) System
The 406 MHz ELT system is an advanced emergency beacon that aids in the search and rescue of aircraft in distress. It consists of several components: 1) Antenna, 2) Internal components such as the battery and electronics, 3) GPS for accurate positioning information, 4) External housing and attachments, 5) Transmitter to send the distress signal, and 6) Control mechanisms such as switches and interfaces. When an aircraft encounters an emergency, the ELT is activated, either manually or automatically upon impact.
The significance of its frequency, 406 MHz, lies in its global monitoring capability by satellites of the Cospas-Sarsat international satellite system for search and rescue. This frequency is part of the radio-wave portion of the electromagnetic spectrum, which includes various frequencies used for different technologies. For instance, 4G cellular signals are approximately 880 MHz, GPS operates at 1.228 and 1.575 GHz, Wi-Fi at 2.4 to 5 GHz, and highway toll sensors at 5.8 GHz. These frequencies are chosen because they are less absorbed by common building materials, enabling better transmission of signals.
Radio receivers, such as those in cell phones or ELTs, work by having incoming electromagnetic waves induce oscillating currents in their antennas. These currents are then amplified and processed into signals that can be used to broadcast information or, in the case of ELTs, to send distress signals to search and rescue teams.