Fighter crews use this term to describe an opportunistic low-altitude flight over hostile territory in search of unplanned targets. Instead of following a strictly briefed strike package against a primary objective, pilots fly these missions under heavy cloud cover to shoot up trains, convoys, or airfields as they find them. The tactic relies on surprise and speed to avoid anti-aircraft fire.
Heard on the job
We dropped under the cloud deck to rhubarb a supply train moving along the coastal railway.
Insider tip
This historic slang originated with British fighter squadrons conducting cross-channel sweeps in poor weather.