On 24 September 1955 the squadron was reformed at RAF Gaydon to operate the Vickers Valiant for reconnaissance duties. It moved to RAF Wyton in November 1955. The squadron's official war role was to carry out pre- and post-strike reconnaissance in support of the RAF's nuclear-armed V-bombers, although the post-strike bomb damage assessment mission was soon abandoned as impracticable in a nuclear war. The squadron carried out frequent long-range survey flights, including mapping Thailand in 1959 and 1961 in Operation "Segment", and surveying Northern Rhodesia, Southern Rhodesia and Bechuanaland (now Zambia, Zimbabwe and Botswana respectively) in 1964 in Operation "Pontifex". Other photo survey duties were carried out to aid relief efforts following natural disasters, with Valiants despatched to survey the damage following the 1960 Agadir earthquake and mapped British Honduras in December 1961 following the devastating Hurricane Hattie. The squadron also carried out Maritime Reconnaissance over the North Atlantic, Norwegian and Barents Seas. In 1964, the Valiant developed metal fatigue problems, with one of the squadron's Valiants was found to have a cracked wing spar in July 1964 during Operation "Pontifex". Inspection of the squadron's aircraft in October 1964 found that only two of eight were fit for further service. The RAF's Valiant fleet, including No. 543's aircraft, were grounded on 26 January 1965.