An RAF officer inspects the hole left by a 22000-lb deep-penetration ‘Grand Slam’ bomb which pierced the reinforced concrete roof of the German submarine pens at Farge north of Bremen Germany. this was the result of a daylight raid mounted by 18 Avro Lancasters of No. 617 Squadron RAF on 27 March 1945 in which two direct hits by ‘Grand Slams’ caused much of the partially-completed roof to collapse.
