AVRO LANCASTER, 1942 AIR MINISTRY H2S RADAR VOLT METER

From the opening years of the war in Europe, the RAF’s Bomber Command and fighter groups found themselves in a constant technological battle with their Luftwaffe counterparts.

Aeronautical radio communication and navigation had been advancing in great strides since the close of WWI but the real break through was the development and implementation of airborne radar and land based airborne radar detection and aircraft interception.

Introduced in 1942, Britain’s Bomber Command had been using the Gee or Oboe systems for radio navigation where measured time delays between two radio signals was used to obtain a positional fix of the aircraft.
This was used for both long distance navigation both to and from the target but also for night time landings upon the bomber’s returns.

Whilst Bomber Command were able to get their bomber streams to the target area, bomber aimers still relied on visual identification of the specific targets which was only made possible by the dropping of incendiary charges during the first wave to illuminate the targeted factories, docks and German Infrastructure.

Weaving about the darkness, dodging anti aircraft fire, night fighters and other Bomber Group aircraft, bombing accuracy in those early years was haphazard to say the least and many aircraft were lost for what was seen as very little gain. Navigators and Bomb Aimers needed to see the target directly.

British scientists had been experimenting with early airborne interception radar since the beginning of 1941 when they discovered that different ground objects gave very different radar signatures. Water, open land and built up areas of cities and towns all produced distinct returns.

By January 1942, development teams, using the latest magnetron generator and scanning antenna were able to demonstrate that they could obtain a startling accurate map of the area below using the new radar.

Known as H2S, the bulky units were initially installed in just a few of the lead bombers and Pathfinder Squadrons and went into operation in late 1942 - early 43. By the following year the early radar system had received a number of upgrades including the H2S Mk. II and ASV Mark II with its installation in additional bombers now in full swing.

Unfortunately the British radar break through did not remain secret for long with an H2S unit being captured by German forces on only its second operation mission on 3rd Feb 1943.

A week later a second unit was captured and with intelligence gathered from downed British crews, they were able to reconstruct a fully operational unit. The quality of the images the H2S displayed startled the Germans and near panic broke out across the Luftwaffe.

Within a few months, Luftwaffe scientists and technicians had developed a suite of radar jamming systems as well as the FuG 350 Naxos radar detector which enabled Luftwaffe fighters to home in on transmissions from the H2S.

The RAF remained unaware of the Naxos until the spring of 1944 when a number of intelligence reports suggested the Germans had developed an H2S detector. A critical error later identified in bomber operations was the fact that bomber crews often turned their H2S sets on well before their approach to thew target and often left them operating all the way home again. 

In July 1944, these suspicions were confirmed when a Ju 88G-1 of 7 Staffel/NJG 2 flew the wrong way on a landing beacon and landed at RAF Woodbridge by accident. 

The crew were arrested before they could destroy their equipment, providing the British researchers with the latest version of the Lichtenstein SN-2 VHF-band radar, the Flensburg radar detector, and the FuG 25a Erstling IFF gear. 

Interrogation of the crew revealed that the Flensburg system detected the RAF bombers' radar emissions and that it was being used as a homing systemand although the H2S system was already being replaced by the new Fishpond systems which gave a far better return image, those aircraft still with the H2S were told to turn them off until when not in use. 

However, German radar advances had now been able to use the British radar signatures to support their Wurzburg gun-laying radar networks and continued to guide night fighters to their targets. 

This in turn saw Bomber Command dispersing hundreds of pounds of metallic ‘chaff' on approach to their targets designed to confuse German radar and also installing rudimentary radar tracking detectors called Boozers which displayed a flashing warning light on the aircraft’s main flying panel alerting the pilot to possible tracking by a night fighter.

This 1942, Air Ministry No 10A 12240 Volt Meter was installed in the first H2S units and is a fascinating artefact of the radar wars between the RAF and the Luftwaffe. 

With its highly detailed 1/72 scale model of the Avro Lancaster mounted above on its magnetic arm and its detailed laminated Fact Sheet, this Recovery Curios Original Vintage Aircraft Instrument Collectable would make an unforgettable and highly prized gift for any aviation enthusiast. 

* Please note that this original Recovery Curios Aircraft Display is also available in a Super Detailed, Large Scale 1/48 version with some astounding and simply awesome detail. Click on the ‘1/48 Scale Model Option' at the top of this page to order.

This Avro Lancaster Instrument comes complete with detailed Scale Model, Mango Wood Stand & Plaque plus Printed Fact Sheet featuring photo of instrument in the aircraft cockpit.

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