Halifax B II srs 1a JP121 with H2S radar
Details about H2S Use in Halifaxes
- H2S was a radar bombing aid used in World War II that was independent of ground stations and carried in the aircraft.
- Early in 1942, two Halifaxes were assigned to the Telecommunications Research Establishment at Swanage and used for the first test flights of the H2S equipment.
- These trials began in April 1942 at Hurn.
- The scanner for the H2S was carried in a Perspex cupola under the rear fuselage. This cupola was later known as a radome.
- At the time of these trials, there were alternative versions of the H2S under study. One used the relatively well-known klystron valve, and the other used the much more powerful but very secret magnetron valve.
- The magnetron-powered H2S was eventually given a high priority.
- On June 7, 1942, the Halifax (V9977) that was carrying the experimental magnetron set crashed near Ross-on-Wye, killing all on board, including five scientists working on H2S development.
- The urgent testing of the H2S continued with Halifax B.II W7711.
- Trials of the magnetron-powered H2S by the Bombing Development Unit were made in late September 1942.
- By mid-January 1943, 35 Squadron had received nine of the first production sets to fit in its Halifaxes. They used these, along with the Stirlings of No. 7 Squadron, to take H2S into operation for the first time.
- This first operation was the bombing of targets in Hamburg on the night of January 30/31, 1943.
- Early results using H2S in operations were hampered by teething problems.
- The full potential of H2S wasn’t achieved until the 3-cm version replaced the early 10-cm model.
- Within a few weeks of its introduction, Bomber Command wanted to expand the use of H2S beyond the Pathfinder Force to all main force heavy bombers other than the Lancasters fitted with 8,000-lb bomb-bay doors.
- The H2S radome became a common sight on later Halifaxes, although few of the Merlin-engined variants had one except for those of 35 and 405 Squadrons at home and 614 in North Africa/Italy.