Flying skylight
Interior of the fuselage of Handley Page Halifax B Mark II, JP321 ‘V’, of No. 614 Squadron RAF, showing some of the many holes caused by splinters from an anti-aircraft rocket which hit the aircraft during an early pathfinding operation over central Europe.

Copyright: © IWM. Original Source: http://www.iwm.org.uk/collections/item/object/205212739
The aircraft was successfully flown back to the Squadron’s base at Celone, Italy, but was struck off charge as a result of the damage.
No. 614 (County of Glamorgan) Squadron is still around, with a lineage that goes back to 1937. However, they have been a non-flying unit since they retired their Vampires in 1957. Their current tasking is as a Joint Cyber Unit (Reserve) based at Northwood.