On 27 September 2011, a flight instructor and student pilot of a Piper Aircraft Corporation PA 28 151 (Warrior) aircraft, registered VH-CIX (CIX), were conducting circuits at Mangalore Airport, Victoria. After completing a stop-and-go on runway 05 and climbing to 1,500 ft above mean sea level (AMSL), the aircraft was turned onto crosswind. When the turn was completed, the instructor of CIX observed a Piper Aircraft Corporation PA-44-180 (Seminole) aircraft, registered VH-KHG (KHG), on downwind, about 30 to 45 m to the right and at the same height. The instructor of CIX immediately assumed control of the aircraft, reducing the engine power to idle and descending about 200 ft.
The flight instructor and student pilot on KHG had joined downwind for runway 05 from a practice instrument approach to the Mangalore runway 23 very high frequency (VHF) omnidirectional radio range (VOR)¹. Soon after, the instructor sighted CIX off to his left flying straight and level, established on a slightly earlier than normal crosswind leg. CIX then passed in front of KHG, about 100 to 200 ft below and 100 m in front.
As CIX was straight and level and established on crosswind when first sighted by KHG, it is likely that the pilots of KHG did not sight CIX until after the airprox² had occurred and CIX had descended.
CIX and KHG were both operated by the same operator. As a result of this serious incident, the operator conducted an internal investigation into the incident and advised the ATSB that they had introduced a procedure whereby, when the wind conditions favoured a take-off towards the north or north-east, aircraft joining the circuit from a practice instrument approach were to descend to an overfly height of 2,000 ft AMSL and join the circuit from the non-active side of the circuit.
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1. A ground-based navigation aid that emits a signal that can be received by appropriately equipped aircraft and represented as the aircraft's bearing (called a 'radial') to or from that aid.
2. An occurrence in which two or more aircraft come into such close proximity that a threat to the safety of the aircraft exists, or may exist, in airspace where separation is a pilot responsibility.