H2X radar
Encyclopedia
H2X radar was an American development of the British H2S radar
, the first ground mapping radar to be used in combat. It was used by the USAAF
during World War II
as a navigation system for daylight overcast and nighttime operations. It used a shorter 3 cm wavelength (10 GHz
frequency) than the H2S, giving a sharper picture (H2S subsequently adopted 3 cm in the Mark III version entering operational service on November 18, 1943, for “Battle of Berlin
”). The first H2X-equipped B-17s arrived in England in early February 1944, and were first used in combat later that month. Those missions where bombing was done by H2X were called "Pathfinder missions" and the crews were called "Pathfinder crews". The radar dish replaced the ball turret of the Pathfinders. In the B-17 the "Mickey set" was installed in the radio room. The H2X on later B-24s was installed in the flight deck behind the co-pilot. In combat areas the Mickey operator directed the pilot on headings to be taken, and on the bomb run directed the airplane in coordination with the bombardier. The first use of the "Mickey" was against Ploesti on April 5, 1944.
Due to the absence of radar maps, in late April 1944 six PR Mk.XVI de Havilland Mosquito
aircraft in the 482nd Bomb Group were equipped with H2X equipment. The idea was to produce photographs of the radar screen during flights over Germany allowing easy interpretation of these radar images in later bombing runs. Three aircraft were subsequently lost in training, and the project was discontinued. A further 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 friendly fire
from a Ninth Air Force P-47. 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.
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.
Post-war
, 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.
H2S radar
H2S was the first airborne, ground scanning radar system. It was developed in Britain in World War II for the Royal Air Force and was used in various RAF bomber aircraft from 1943 to the 1990s. It was designed to identify targets on the ground for night and all-weather bombing...
, the first ground mapping radar to be used in combat. It was used by the USAAF
United States Army Air Forces
The United States Army Air Forces was the military aviation arm of the United States of America during and immediately after World War II, and the direct predecessor of the United States Air Force....
during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
as a navigation system for daylight overcast and nighttime operations. It used a shorter 3 cm wavelength (10 GHz
GHZ
GHZ or GHz may refer to:# Gigahertz .# Greenberger-Horne-Zeilinger state — a quantum entanglement of three particles.# Galactic Habitable Zone — the region of a galaxy that is favorable to the formation of life....
frequency) than the H2S, giving a sharper picture (H2S subsequently adopted 3 cm in the Mark III version entering operational service on November 18, 1943, for “Battle of Berlin
Battle of Berlin (air)
The Battle of Berlin was a British bombing campaign on Berlin from November 1943 – March 1944. The campaign was not limited solely to Berlin. Other German cities were attacked to prevent concentration of defences in Berlin, and Bomber Command had other responsibilities and operations to conduct...
”). The first H2X-equipped B-17s arrived in England in early February 1944, and were first used in combat later that month. Those missions where bombing was done by H2X were called "Pathfinder missions" and the crews were called "Pathfinder crews". The radar dish replaced the ball turret of the Pathfinders. In the B-17 the "Mickey set" was installed in the radio room. The H2X on later B-24s was installed in the flight deck behind the co-pilot. In combat areas the Mickey operator directed the pilot on headings to be taken, and on the bomb run directed the airplane in coordination with the bombardier. The first use of the "Mickey" was against Ploesti on April 5, 1944.
Due to the absence of radar maps, in late April 1944 six PR Mk.XVI de Havilland Mosquito
De Havilland Mosquito
The de Havilland DH.98 Mosquito was a British multi-role combat aircraft that served during the Second World War and the postwar era. It was known affectionately as the "Mossie" to its crews and was also nicknamed "The Wooden Wonder"...
aircraft in the 482nd Bomb Group were equipped with H2X equipment. The idea was to produce photographs of the radar screen during flights over Germany allowing easy interpretation of these radar images in later bombing runs. Three aircraft were subsequently lost in training, and the project was discontinued. A further twelve PR Mk.XVI de Havilland Mosquito
De Havilland Mosquito
The de Havilland DH.98 Mosquito was a British multi-role combat aircraft that served during the Second World War and the postwar era. It was known affectionately as the "Mossie" to its crews and was also nicknamed "The Wooden Wonder"...
aircraft of the 25th Bomb Group (Reconnaissance) of the Eighth Air Force
Eighth Air Force
The Eighth Air Force is a numbered air force of the United States Air Force Global Strike Command . It is headquartered at Barksdale Air Force Base, Louisiana....
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 friendly fire
Friendly fire
Friendly fire is inadvertent firing towards one's own or otherwise friendly forces while attempting to engage enemy forces, particularly where this results in injury or death. A death resulting from a negligent discharge is not considered friendly fire...
from a Ninth Air Force P-47. 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.
In the Pacific theater
Pacific War
The Pacific War, also sometimes called the Asia-Pacific War refers broadly to the parts of World War II that took place in the Pacific Ocean, its islands, and in East Asia, then called the Far East...
, B-29’s were equipped with the improved H2X radar called the AN/APQ-13
AN/APQ-13
AN/APQ-13 radars were a ground scanning radar developed by Bell Laboratories, Western Electric, and MIT as an improved model of the airborne H2X radar, itself developed from the first ground scanning radar, the British H2S radar. They were used on B-29s during World War II in the Pacific theater...
, 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
Superheterodyne receiver
In electronics, a superheterodyne receiver uses frequency mixing or heterodyning to convert a received signal to a fixed intermediate frequency, which can be more conveniently processed than the original radio carrier frequency...
. 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.
Post-war
Post-war
A post-war period or postwar period is the interval immediately following the ending of a war and enduring as long as war does not resume. A post-war period can become an interwar period or interbellum when a war between the same parties resumes at a later date...
, the AN/APQ-13
AN/APQ-13
AN/APQ-13 radars were a ground scanning radar developed by Bell Laboratories, Western Electric, and MIT as an improved model of the airborne H2X radar, itself developed from the first ground scanning radar, the British H2S radar. They were used on B-29s during World War II in the Pacific theater...
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
AN/CPS-9
The AN/CPS-9 radar, the first radar specifically designed for meteorological use, was unveiled by the Air Weather Service in 1954.- AN/CPS-9 installations :...
system in 1949.