F51

F51 most often refers to: North American F-51 Mustang, an American fighter aircraft

F51 may also refer to: Farman F.51, a French maritime reconnaissance flying boat , a Tribal-class destroyer of the Royal Navy , a Blackwood-class frigate of the Royal Navy , an armed merchant cruiser of the Royal Navy , a Talwar-class frigate of the Indian Navy Nonorganic sleep disorder