Swarms of drones, David Hambling explains (in Swarm Troopers), might follow the model of flocks of geese to fly further together:
Large birds are often seen flying in skeins, V-shaped formations, with the birds spaced at regular intervals.
[…]
The tip of a wing, whether it is a goose or an Airbus 380, generates a whirlpool of air known as a tip vortex. This produces a downwash beneath the wings and an upwash just outside the wing. The vortex is actually a miniature tornado that may contain airspeeds of 100mph and may be about the same size of the span of the wing that produces it. The vortex from an airliner can be dangerous, as it is strong enough to flip a light aircraft right over. Close to the ground, the vortex from an aircraft taking off may persist for more than a minute.
[…]
By flying just to the side and behind, a following goose gets the benefit of the updraft provided by its companion. This gives it free lift, equivalent to flying downhill.
[…]
Naturalists’ estimate that skeins of geese gain a 70% range advantage by flying in formation rather than individually. A detailed aerodynamic study by the US Air Force Air Vehicles Directorate found that formations of nine aircraft could achieve an 80% increase in range over the distance they could fly alone.
Begun, the drone wars have. Small drones are cheap and effective. Big drones, airplanes, and any static target you can Google is vulnerable.
In ‘General Kenney Reports’, Kenney’s memoir of the Pacific War, he mentions Lindberg showing up quasi-illegally. Kenney put the man who babied a single-engine plane across the Atlantic in charge of training P-38 pilots to baby their fuel use, and P-38 ranges doubled.
One has to wonder what the aerodynamics of the huge WW II bomber formations were. Often hundreds of large aircraft flew in tight formations.
PS. “Twelve O’Clock High” is still one of the best war films ever made.