NS11 had taken off from
RAF Pulham in
Pulham St Mary,
Norfolk, around midnight on the night of 14/15 July 1919 and was heading over the
North Sea on a
mine-hunting patrol. In the early hours of 15 July, she was seen to fly beneath a long "greasy black cloud" off the village of
Cley next the Sea on the Norfolk coast when locals reported an abnormal noise from her engines (which may have suggested she was experiencing engine trouble). The
Sheringham lifeboat was launched but its crew could only find a small part of the aluminium wreckage. The accident occurred less than 48 hours after the airship
R34 arrived at RAF Pulham after a successful double-crossing of the Atlantic Ocean, including the first-ever east–west crossing by air. ==Cause==