Mid-air plane collision ‘unusual’, investigation declares
A mid-air plane crash that killed four people in Mangalore has been declared as "unusual" by safety authorities, with weather and radio recordings key to the ongoing investigation.
The preliminary findings into the February 19 horror mid-air smash shows both aircraft were operating under instruments at the time of the deadly collision.
The report released on Thursday said the Beechcraft Travel Air and the Piper Seminole aircraft crashed 8km south of Mangalore airport at an altitude of 4,100 ft.
ATSB Chief Commissioner Greg Hood said while the "investigation is quite complex" they would be looking at every possible cause of the crash.
"Both aircraft were operating under instrument flight rules which means both aircraft were permitted to operate into cloud," Mr Hood said.
"That means we will be particularly focused on the prevailing weather conditions at the time, the air traffic control aspects of the accident and we'll also be looking at the classification of the airport and the visibility from both the aircraft."
The collision killed experienced pilots Christiaan Gobel and Peter Phillips as well as their passengers Ido Segev and a Thai national in her 20s.
The investigation revealed the Travel Air departed Tyabb airport for a training flight to Shepparton to Mangalore about 10.55am.
The Seminole advised air traffic control at 11.11am they were taxiing for departure from Mangalore for a round-trip via Essendon and Shepparton.
When the Travel Air began its descent, Air Traffic Control notified of the departing Seminole however the aircraft collided mid-air at 11.24am.
Both aircraft plummeted to the ground, the bodies of those aboard later found inside the wreckage.
The Seminole travelled 500m to the east before it crashed into an open field while the Travel Air continued north and ended up 1.4km away from the collision point.
Debris was found in area ranging from 1.6 km to the north-north-east (correct) and about 200m to the west of the Hume Highway.
At the time Victoria Police Inspector Peter Koger said it was a "devastating" scene first responders had witnessed.
"You couldn't even tell it was an aircraft," he said of the Mangalore wreckage.
"It is a tragedy."
The ATSB said recovered radios, weather conditions and recorded area frequency calls will be the focus as the investigation moves forward.
A final report is expected to be completed next year.
Originally published as Mid-air plane collision 'unusual', investigation declares