This work was carried out at Devonport Dockyard in 1964. The deck forward of the cargo hatch was cleared of all obstructions, and strengthened for helicopter use. A small deckhouse used to support the gun emplacements was retained, although no guns were fitted, and it was used by the Flight Deck Officer as a helicopter control position. Below deck, two 10,000 gallon aviation fuel tanks were installed at the fore end of the tank deck, and refuelling positions provided at the fore end of the flight deck. The tanks were sealed off by a bulkhead and the rest of the space used for stores, workshops and accommodation. Finally the bow doors were sealed, as they would no longer be needed. The flight deck was large enough for two Westland Wessex helicopters with rotors turning, or six could be parked with rotors folded. Renamed she proved extremely useful in service, and many lessons were learned that would be incorporated into "Engadine".