No. 100 Group RAF
No. 100 Group was a special duties group within RAF Bomber Command. The group was formed on 11 November 1943 to consolidate the increasingly complex business of electronic warfare and countermeasures in 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, using a range of electronic 'homers' fitted to de Havilland Mosquito fighters which detected night fighter radar and radio emissions and allowed the RAF fighters to home in onto the Axis aircraft and either shoot them down or disrupt their missions against the bomber streams. Other Mosquitoes would patrol around Luftwaffe fighter airfields ready to attack night fighters as they landed.
This constant harassment had a detrimental effect on the morale and confidence of many Luftwaffe crews and indirectly led to a high proportion of aircraft and aircrew wastage from crashes as night fighters hurried in to land to avoid the Mosquito threat.
From 1944–45, the Mosquitos 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 Wing Commander Branse Burbridge of 85 Squadron, with 21 claims from 1944–45.
The bomber squadrons of 100 Group utilised various specialist electronic jamming devices to disrupt German radio communications and radar. During 100 Group's existence over 32 different devices were evaluated and used. Specially equipped 100 Group aircraft would fly in the bomber stream. Much of this equipment was developed at the Telecommunications Research Establishment.
Special equipment used included Airborne Cigar jammer, Jostle, Mandrel, Airborne Grocer, Piperack, Perfectos, Serrate, Corona, Carpet and Lucero, used against German equipment such as Lichtenstein, Freya, and Wurzburg radars.
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 Handley Page Halifaxes, Short Stirlings, Vickers Wellingtons, Fortresses and Liberators carrying electronic jamming equipment. The group also operated the Bristol Beaufighter for a short time.The group disbanded on 17 December 1945. During its existence it had one commander, Air Vice-Marshal Edward Addison.
| Squadron | Aircraft | First 100 Group operation | Base |
| 192 | Mosquito II, B.IV, B.XVI, Wellington B.III, Halifax IV | December 1943 | RAF Foulsham |
| 141 | Beaufighter VI, Mosquito II, VI, XXX | December 1943 | RAF West Raynham |
| 239 | Mosquito II, VI, XXX | 20 January 1944 | RAF West Raynham |
| 515 | Mosquito II, VI | 3 March 1944 | RAF Little Snoring, RAF Great Massingham |
| 169 | Mosquito II, VI, XIX | 20 January 1944 | RAF Little Snoring |
| 214 | Fortress II, III | 20/21 April 1944 | RAF Sculthorpe, RAF Oulton |
| 199 | Stirling B.III, Halifax B.III | 1 May 1944 | RAF North Creake |
| 157 | Mosquito XIX, XXX | May 1944 | RAF Swannington |
| 85 | Mosquito XII, XVII | 5/6 June 1944 | RAF Swannington |
| 23 | Mosquito VI | 5/6 July 1944 | RAF Little Snoring |
| 223 | Liberator VI, Fortress II, III | September 1944 | RAF Oulton |
| 171 | Stirling II, Halifax III | 15 September 1944 | RAF North Creake |
| 462 | Halifax III | 13 March 1945 | RAF Foulsham |
Other units and stations:
- No. 1692 Flight RAF based at RAF Little Snoring
- No. 1699 Flight RAF based at RAF Oulton to train Fortress crews for 214 Squadron
- No. 100 Group Communications Flight at RAF West Raynham and then RAF Swanton Morley
- No. 80 Wing RAF from November 1943 based at Radlett Aerodrome, controlled Meacon beacons and other radio counter measures and intelligence work.