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
 * HMS Ashanti (F51), a Tribal-class destroyer of the Royal Navy
 * HMS Grafton (F51), a Blackwood-class frigate of the Royal Navy
 * HMS Laurentic (F51), an armed merchant cruiser of the Royal Navy
 * INS Trikand (F51), a Talwar-class frigate of the Indian Navy
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