This is the 2115th most frequent French word.
aériennes
"Relating to the air or aviation."
In this sentence, 'aériennes' describes 'forces', indicating their association with operations in the air.
L'armée dispose de forces aériennes pour les missions à haute altitude.
The army has air forces for high-altitude missions.
The term 'aériennes' here attributes the nature of the photographs being taken from the air.
Les photographies aériennes aident à cartographier les régions difficiles d'accès.
Aerial photographs help to map out regions that are hard to access.
Here, 'aériennes' is used as an adjective modifying 'compagnies', referring to companies related to air travel.