251 aircraft-98 Wellingtons, 76 Lancasters, 41 Halifaxes, 36 Stirlings. 12 aircraft- 7 Wellingtons, 3 Lancasters, 1 Halifax, 1 Stirling - lost, 4·8 per cent of the force.
The Pathfinders introduced new techniques on this night, splitting their aircraft into 3 forces: 'illuminators', who lit up the area with white flares; 'visual markers', who dropped coloured flares if they had identified the aiming point; then 'backers¬up', who dropped all-incendiary bomb loads on to the coloured flares. This basic pattern - illuminating, marking and backing-up - would form the basis of most future Pathfinder operations with proper target-indicator bombs and various elec¬tronic bombing aids being employed as they became available. The weather was clear and the Pathfinder plan worked well; heavy bombing of the target followed. Bremen confirms that this was a successful raid.
source: The Bomber Command War Diaries, Martin Middlebrook and Chris Everitt
Bomber Command Museum Monthly ORB