H2X

The H2X radar, nicknamed the "Mickey set", provided the USAAF with ground mapping capability (for navigation) during daylight overcast and nighttime operations in World War II.

The H2X system replaced the British H2S radar. It used a shorter 3 cm wavelength that gave a sharper picture (H2S would use 3 cm in the Mark III version entering service in December 1944). The U.S. converted fifty B-24 Bombers into Pathfinder Aircraft equipped with the H2X radars. The radar dish replaced the ball turret of the Pathfinders. The "Mickey set" was installed in the radio room and navigational and bombing information was given to the Navigator and Bombardier. These aircraft recorded 1132 sorties during World War II. The H2X in production was called the AN/APS-15.

In Europe several P-38 fighters were also converted to carrying H2X radar in the nose, along with an operator/navigator to obtain radar maps of German targets but plans to produce the variant in quantity never materialized. Twelve PR Mk.XVI de Havilland Mosquito aircraft of the 25th Bomb Group (Reconnaissance) of the Eighth Air Force were fitted with H2X and beginning in May 1944 flew radar mapping night missions until February 1945. The sets tended to overload the Mosquito's electrical system and occasionally exploded. Mickey aircraft had the highest loss, abort, and mission failure rates of the otherwise successful Mosquito reconnaissance aircraft and were severely curtailed after February 19, 1945. Three were lost to enemy action and one was shot down by a Ninth Air Force P-47.

In the Pacific theater, B-29’s were equipped with the improved H2X radar called the AN/APQ-13, a ground scanning radar developed by Bell, Western Electric, and MIT. The radome was carried on the aircraft belly between the bomb bays and was partially retractable. The radar operated at a frequency of 9,375 ± 45 megahertz and used a superheterodyne receiver. The radar was used for high altitude area bombing, search and navigation. Computation for bombing could be performed by an impact predictor. A range unit permitted a high degree of accuracy in locating beacons.

After the war, late 1945, the AN/APQ-13 became the first military radar converted to a domestic peacetime application as a storm warning radar. About thirty systems were converted and installed on military bases. It was replaced by the AN/CPS-9 system in 1949.

See also

• List of World War II electronic warfare equipment

References

• Freeman, Roger A. The Mighty Eighth War Diary (1990). ISBN 0879384956 page 240