  Airplane sensors and on-board equipment collect an increasingly large amount
of maintenance data during flights that are used for airplane maintenance. We
propose to download part of the data during airplane's descent via a cellular
base station (BS) located at the airport. We formulate and solve an offline
optimization problem to quantify how much data can be offloaded in a
non-dedicated band while ensuring that the interference at the terrestrial BSs
in the vicinity of the airport remains below a maximum allowable threshold. Our
problem allows for adaptive tuning of transmit power, number of frequency
channels to be used, and beamforming according to the position of the plane on
the descent path. Our results show that during the last 5 minutes of descent,
in the microwave band the plane can offload up to 5 GB of maintenance data in a
20~MHz band, while in the mmWave band the plane can offload up to 24 times more
data in a 1~GHz band. Beamforming, power and bandwidth tuning are all crucial
in maintaining a good performance in the mmWave band while in the microwave
band, dynamic tuning of bandwidth does not improve the performance much.
