Keeping a plane in the air requires extremely expensive amounts of fuel. These planes would otherwise be active on routes, at airport gates, on the ramp tempor

Keeping a plane in the air requires extremely expensive amounts of fuel. These planes would otherwise be active on routes, at airport gates, on the ramp temporarily, in maintenance, or stored at a base owned or partnered with by the airline (in the worst case). A big part of running an airline is making sure you are using your fleet to make money since planes are expensive to own, maintain, insure, and fly. These airlines may be switching over to freight for supply runs but don't have their own storage capacity for the planes that would normally be flying now-closed passenger routes and can't be repurposed for freight.