Bomber Command created a card for each aircraft that failed to return from an operational flight.
The amount of data recorded on the cards varied, but normally included the names of the crew and their fate. In some cases, information on the route taken, the equipment on board, the bomb load and feedback from survivors is also included.
The notes on the reverse of the cards are usually hard to read (due to the “spider” handwriting), but it is usually possible to decipher the bulk, thereby ensuring some understanding of the content.
The surviving cards are held by the Ministry of Defence Air Historical Branch.
However, the RAF Museum holds copies on microfilm and provide a copying service.