 Agincourt 's first assignment , together with her half @-@ sister Northumberland , was to tow a floating drydock from England to Madeira where it would be picked up by Warrior and Black Prince and taken to Bermuda . The ships departed the Nore on 23 June 1869 , loaded down with 500 long tons ( 510 t ) of coal stowed in bags on their gun decks , and transferred the floating dock 11 days later after an uneventful voyage . Agincourt was assigned to the Channel Fleet upon her return and she became the flagship of the second @-@ in @-@ command of the fleet until she began a refit in 1873 . 
