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. Wikipedia
Electronic warfare: Boeing B-17 Flying Fortress, Consolidated B-24 Liberator, Handley Page Halifax, Short Stirling, Vickers Wellington
Group badge: The head of Medusa azure/or/sable.
Motto(s): Confound and Destroy