No. 100 Group RAF

No. 100 (Bomber Support) Group was a special duties group within RAF Bomber Command. It was formed on 11 November 1943 to consolidate the increasingly complex business of electronic warfare and countermeasures within one organisation. The group was responsible for the development, operational trial and use of electronic warfare and countermeasures equipment. It was based at RAF stations in East Anglia, chiefly Norfolk.

The group was a pioneer in countering the formidable force of radar-equipped Luftwaffe night fighters, utilising a range of electronic 'homers' fitted to de Havilland Mosquito fighters which detected the night fighter's various radar and radio emissions and allowed the RAF fighters to home in onto the Axis aircraft and either shoot them down or at the very least disrupt their missions against the bomber streams. Other Mosquitoes would patrol around the known Luftwaffe fighter airfields ready to attack any landing night fighters they came across.

This constant harassment had a detrimental effect on the morale and confidence of many Luftwaffe crews, and indirectly led to a high proportion of both aircraft and aircrew wastage from crashes as night fighters hurried in to land to avoid the Mosquito threat (real or imagined).

During 1944-5, the Mosquitoes of 100 Group claimed 258 Luftwaffe aircraft shot down for 70 losses. The gradually increasing threat from the RAF fighters also created what the Luftwaffe crews nicknamed 'Moskito Panik' as the night fighter crews were never sure when or where they may come under attack from the marauding 100 Group fighters.

Top Mosquito ace with 100 Group was 85 Squadron's Wing Commander Branse Burbridge with 21 claims 1944-45.

The bomber squadrons of 100 Group utilised various specialist electronic jamming devices to disrupt enemy radio communications and radar. During 100 Group's existence over 32 different devices were evaluated and used. Specially equipped 100 Group aircraft would fly within the bomber stream. Much of this equipment was developed at the Telecommunications Research Establishment (TRE).

Special equipment used included Airborne Cigar (ABC) jammer, Jostle (jammer), Mandrel (jammer), Airborne Grocer (jammer), Piperack (jammer), Perfectos (homer), Serrate (homer), Corona (spoofer), Carpet (jammer) and  Lucero (homer), and were used against German equipment such as Lichtenstein, Freya, and Würzburg radars.

The combination of the Pathfinders' operations, the activities of No. 100 Group, the British advantage in radar, jamming and Window techniques, combined with intelligent attacking tactics, as well as the discipline and bravery of the RAF crews, have been remarkable. We had our (sic) severe problems in trying to defend Germany in the air

Order of battle
No. 100 Group was headquartered at Bylaugh Hall, Norfolk from January 1944, a central location from which to administer the group's airfields in north Norfolk. No 100 Group operated from eight airfields with approximately 260 aircraft, 140 of which were various marks of Mosquito night fighter intruders with the remainder consisting of Halifaxes, Stirlings, Wellingtons, Fortresses and Liberators carrying electronic jamming equipment. The group also operated the Beaufighter for a short time.

The group disbanded on 17 December 1945. During its existence it had one commander, Air Vice-Marshal Edward Addison.

Other units and stations:
 * No. 1692 Flight RAF based at RAF Little Snoring
 * No. 1699 Flight RAF based at RAF Oulton to train Boeing Fortress crews for 214 Squadron
 * No. 100 Group Communications Flight at RAF West Raynham and then RAF Swanton Morley
 * No. 80 (Signals) Wing from November 1943 based at RAF Radlett, controlled Meacon beacons and other radio counter measures and intelligence work.