American Airborne Landings in Normandy - Pathfinders

Pathfinders

The 300 men of the pathfinder companies were organized into teams of 14-18 paratroops each, whose main responsibility would be to deploy the ground beacon of the Rebecca/Eureka transponding radar system, and set out holophane marking lights. The Rebecca, an airborne sender-receiver, indicated on its scope the direction and approximate range of the Eureka, a responsor beacon. The paratroops trained at the school for two months with the troop carrier crews, but although every C-47 in IX TCC had a Rebecca interrogator installed, to keep from jamming the system with hundreds of signals, only flight leads were authorized to use it in the vicinity of the drop zones.

Despite many early failures in its employment, the Eureka-Rebecca system had been used with high accuracy in Italy in a night drop of the 82nd Airborne to reinforce the Fifth Army at Salerno. However a shortcoming of the system was that within 2 miles (3.2 km) of the ground emitter, the signals merged into a single blip in which both range and bearing were lost. The system was designed to steer large formations of aircraft to within a few miles of a drop zone, at which point the holophane marking lights or other visual markers would guide completion of the drop.

Each drop zone (DZ) had a serial of three C-47 aircraft assigned to locate the DZ and drop pathfinder teams, who would mark it. The serials in each wave were to arrive at six minute intervals. The pathfinder serials were organized in two waves, with those of the 101st Airborne arriving a half hour before the first scheduled assault drop. These would be the first U.S. and possibly the first Allied troops to land in the invasion. The three pathfinder serials of the 82nd Airborne were to begin their drops as the final wave of 101st Airborne paratroopers landed, thirty minutes ahead of the first 82nd Airborne drops.