Many aircraft have been lost at sea, sometimes resulting in whole crash sites surviving on the seabed. Thousands of British, American and German military aircraft crashed in UK waters during the Second World War, but we can also come across military aircraft lost in peacetime, and the crash sites of civil aircraft. As well as being memorials to the aircrew who lost their lives in these crashes, air crash sites are an important source of social history and identity. Aircrash sites at sea are interesting to archaeologists because they may be much better preserved then crash sites on land, and in some cases they are the only surviving relics of particular aircraft types and models. All military aircraft crash sites in UK waters are protected automatically under the Protection of Military Remains Act 1986.