Flight 441 departed Whenuapai at 08:21 for a flight to Tauranga (TRG). En route to Tauranga, the DC-3 crashed into a face of a rock of the Kaimai Range at an altitude of 2460 feet. PROBABLE CAUSE: “A strong downward current in the lee of the Kaimai Range close to the Gordon quarry. This downward current carried the aircraft below the level of the crests of the range, where under the conditions prevailing at the time, the aircraft encountered an area of extreme turbulence in which it was impossible for the pilot to regain effective control and recover height. Contributory causes: a) The captain of the aircraft was unaware of his true position and initiated a premature descent. However, it must be appreciated that he decided to descend only to the level officially designated as the minimum safe altitude in the area of his descent. b) The decision of the Civil Aviation authorities to classify the Kaimai Range as non-mountainous terrain for the purpose of determining the safe altitude for the route. c) The misleading forecast of the upper wind between Wenuapai and Tauranga.”