H2X was used by the USAAF during World War II as a navigation system for daylight overcast and nighttime operations.
It was introduced as an improvement of the earlier H2S set, which had been supplied to the US to aid in the war effort.
While the RAF Bomber Command utilized ground mapping radar as an aid to night area bombing, the primary use by the USAAF was as a fallback, to allow cities to be bombed even when hidden by cloud cover, an issue that had dogged their policy of precision daylight bombing since the start of the war, especially in cloud-prone Europe.
With H2X, a city could be located and a general area targeted, night or day, cloud cover or no, with equal accuracy.
H2X used a shorter 3 cm "centimetric" wavelength (10 GHz frequency) than the H2S, giving a higher angular resolution and thus a sharper picture, which allowed much finer details to be discerned, aiding in target identification.
H2S subsequently also adopted 3 cm in the Mark III version entering operational service on November 18, 1943, for “Battle of Berlin”).

H2X is not known to have ever been spotted by the German FuG 350 Naxos radar detector, due to that receiving device's specific purpose being to spot the original British H2S equipment's lower frequency, 3 GHz emissions.
H2X was used by the USAAF during World War II as a navigation system for daylight overcast and nighttime operations. It was introduced as an improvement of the earlier H2S set, which had been supplied to the US to aid in the war effort. While the RAF Bomber Command utilized ground mapping radar as an aid to night area bombing, the primary use by the USAAF was as a fallback, to allow cities to be bombed even when hidden by cloud cover, an issue that had dogged their policy of precision daylight bombing since the start of the war, especially in cloud-prone Europe. With H2X, a city could be located and a general area targeted, night or day, cloud cover or no, with equal accuracy. H2X used a shorter 3 cm "centimetric" wavelength (10 GHz frequency) than the H2S, giving a higher angular resolution and thus a sharper picture, which allowed much finer details to be discerned, aiding in target identification. H2S subsequently also adopted 3 cm in the Mark III version entering operational service on November 18, 1943, for “Battle of Berlin”).
H2X is not known to have ever been spotted by the German FuG 350 Naxos radar detector, due to that receiving device's specific purpose being to spot the original British H2S equipment's lower frequency, 3 GHz emissions.
H2X