[2] The Joan-Eleanor system was developed from late 1942 onwards for the US Office of Strategic Services (OSS) by DeWitt R. Goddard and Lt. Cmdr.
Because of the low power and the unit's limited range, the transmissions were virtually undetectable and the Germans were unaware of the system.
The antenna was a simple dipole attached to the top of the unit and the only controls were for regeneration and fine tuning.
Since 25th Bomb Group personnel flew Joan-Eleanor missions for OSS, Watton wished credit for these in monthly operational tabulations.
For J-E missions the rear-fuselage compartment, aft of the bomb-bay, was fitted with an oxygen system and modified to accept the SSTR-6 transceiver and wire recorder, with an operator sitting on a cramped seat, and accessed through a side hatch.
The first successful operational use of the system was made on 22 November 1944 by Stephen H. Simpson; he recorded transmissions from an agent codenamed "Bobbie" while circling at 30,000 feet (9,100 m) over the occupied Netherlands.
On 13 March 1945, HQ 8th AF ordered the OSS J-E Project transferred to the 492nd Bomb Group's Liberator base at RAF Harrington, Northamptonshire.
The 25th BG aircrew flew the OSS Mosquito JE missions until 492nd men completed training on this aircraft type.