Penetration of 450-480MHz through the shell of an airplane would, on the ground,require a transmission strength of approximately .4dB/m at a distance of 1 kilom

Penetration of 450-480MHz through the shell of an airplane would, on the ground,require a transmission strength of approximately .4dB/m at a distance of 1 kilometer, which is doable by most measures, but would quickly become unrealistic as the plane gained altitude. https://pure.tue.nl/ws/files/68269081/560768.pdf https://pure.tue.nl/ws/files/68269081/560768.pdf