"Melbourne" struck just aft of "Voyager"s bridge structure, rolling the destroyer to starboard before cutting her in half. "Voyager"s forward boiler exploded, briefly setting fire to the bow of the carrier before it was extinguished by seawater. The destroyer's forward section sank quickly, due to the weight of the two gun turrets. The aft section did not begin sinking until half an hour after the collision, and did not completely submerge until just after midnight. Messages were sent to the Fleet Headquarters in Sydney immediately after the collision, although staff in Sydney initially underestimated the extent of the damage to "Voyager". "Melbourne" launched her boats almost immediately after the collision to recover survivors, and the carrier's wardroom and C Hangar were prepared for casualties. At 9:58 pm, "Melbourne" was informed that search-and-rescue boats from HMAS "Creswell", helicopters from HMAS "Albatross" (Naval Air Station Nowra), and five "Ton" class minesweepers had been despatched to assist in the search.