At 14:28 hours Flight 4374 had levelled out at 3000 feet with the undercarriage and flaps up and was being radar vectored for an ILS approach to Auckland Airport. When visual flight conditions were encountered and the captain commenced the descent the aircraft was 9 miles from the runway threshold at an airspeed of approximately 165 knots and in a good position to carry out a normal descent and approach for a landing on runway 05. About one minute later, at 2 minutes 14 seconds prior to colliding with the sea, the aircraft’s IAS had increased to 211 knots (11 knots in excess of the company’s stipulated Vno) and the aircraft was passing through 1436 feet. Some 1 minute 20 seconds prior to the accident the aircraft’s engine power was probably reduced to the minimum recommended setting for a descent. During the base turn the engine power was probably increased as the aircraft maintained an essentially constant altitude and airspeed during this turn. At this point the flaps were still retracted and the aircraft was not aligned with the runway. At that moment a heavy shower was obscuring the runway threshold. The first officer was not able to see any approach or runway lights. The aircraft descended until it collided with the water of Manukau Harbour, 1025 m west of the runway 05 threshold. PROBABLE CAUSE: “The accident was probably caused by the crew being misled, by a visual illusion in conditions of reduced visibility, into believing they were at a safe height and consequently failing to monitor the flight instruments sufficiently to confirm their aircraft maintained a safe approach path.”