5G technology in itself is not harmful to aviation safety; on the contrary, it could help in the future with its communication and positioning capabilities.The debate right now is about the impact of these 5G transmissions in airport areas on the Radar Altimeter (RALT). Each aircraft uses two R ALT units to send low power radio waves to the ground (Ⅰ Watt) and measure the height between the landing gear wheels and the ground with high accuracy by receiving the echo reflected from the ground (see Figure Ⅰ ).This radar return signal is considerably weaker than the initial Ⅰ Watt.The main purpose of R ALT is to correctly schedule the flare manoeuvre before touchdown in automated landing. Another important purpose is to protect the flight from terrain proximity in the terminal phases of the flight. R ALT is a major information source for the Autoland function of the AFCS.A/T, EGPWS /TAWS, and TCAS. Without correct R ALT measurements, the flare manoeuvre could be too early or too late, and consequently dangerous. A late flare could cause a damaging impact of the landing gear to the runway, or at best a bouncy landing. Autoland is primarily affected.
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