Between June 1956 and August 1958, "Centaur" underwent her partial modernisation at Devonport Dockyard. This involved the installation of two BS4 steam catapults forward, the removal of the Bofors guns on the flight deck, improved air operations facilities and the addition of a Type 963 blind-landing radome at the rear of the island. Some work was also done on a further slight extension on the port-side, to enable a six-degree angled flight deck to be used. Her arrestor cables were not upgraded at this stage, however. This was rectified in her 1960–1961 refit, when five arrestor wires were fitted.