The first major passenger-plane crash with fatal results in the then nearly 20 years of commercial flying in New Zealand occurred on 23 October 1948, when the Lockheed Electra airliner Kaka, operated by the State-owned National Airways Corporation, went missing on a routine flight from Palmerston North to Hamilton. Less than half an hour after take-off, the Kaka literally disappeared from sight and sound, and it was nearly seven days, after an intensive air and land search over 450 square miles of rugged country, before the wrecked fuselage was discovered half-buried in the snow 3,000 ft up on the slopes of Mt. Ruapehu. All 13 occupants of the plane had perished. In the disintegrated debris of the machine was found the air-speed indicator which, jammed at a reading of 150 m.p.h., furnished some evidence of the terrific force of the impact when the plane struck the mountainside. A Court of Inquiry found that the Kaka was off course at the time of accident, due to an error in the pilot's calculations.

In the following year, on 18 March 1949, another National Airways passenger liner, the Kereru, a Lodestar aircraft with 15 persons on board, smashed into the Tararua foothills near Waikanae, at an altitude of 1,500 ft, and burst into flames on impact. There were no survivors. The Kereru was on a trunk flight from Auckland to Dunedin and crashed into the hillside a few minutes after receiving its landing instructions from the control tower at the Paraparaumu airport, 13 miles away. At the time of the accident the pilot was flying under visual flight rules, for which he had authority, due to a very low cloud base. Wreckage was sighted two hours after the Kereru had been posted overdue, but this turned out to be the remains of an Air Force Ventura lost three years before on a training flight. Shortly afterwards, however, searching aircraft sighted burning debris on the wooded hillside east of Waikanae, and not far from the Otaki River mouth. This was the remains of the Kereru, and when a rescue party reached the scene after a hazardous trek through the bush, they found parts of the burnt-out plane spread over a wide area. In the view of the Royal Commission of Inquiry the tragedy was the result of faulty navigation.