What happened
On July 22, 2000, at approximately 17:00, two aircraft were involved in a mid-air collision at the SSKS aerodrome in Cachoeira do Sul, Brazil. The first aircraft, a PT-DAD (Mooney M20-F), had departed for a local flight over the pilot's properties. Approximately twenty minutes later, an Aerobee 115 (PP-GBI) departed the same airfield for a daytime flight training mission involving an instructor and a student.
As the PT-DAD returned to the airfield, the pilot established a final approach for runway 30. Simultaneously, the PP-GBI was performing a left-hand base leg for the same runway. The pilot of the PT-DAD reported that he only noticed the other aircraft when it was almost directly overhead. During the landing phase, the PP-GBI collided with the PT-DAD, with its rear fuselage striking the upper forward section of the PT-DAD. The impact was severe enough that the PP-GBI's tail section was severed by the PT-DAD's propeller. The two aircraft remained entangled until they came to a complete stop on the runway. There were no injuries among the three occupants involved.
The investigation
CENIPA's investigation revealed a series of critical regulatory and operational failures. The investigation found that the PP-GBI was operating with a malfunctioning VHF radio; the crew had decided to proceed with the flight despite the lack of communication equipment. Furthermore, the pilot of the PT-DAD was operating with an expired pilot license and medical certificate, both of which had been invalid for over seven years. The PT-DAD was also flying with an expired airworthiness certificate.
Communication played a decisive role in the accident. The pilot of the PT-DAD attempted to broadcast his position on an incorrect frequency (130.55 MHz instead of the standard 123.45 MHz), and because the PP-GBI was flying without radio capability, no bilateral coordination could occur. The investigation also noted that the local flying club was aware of the pilot's expired credentials but had failed to take administrative action or report the irregularities to the authorities.
Findings
- Lack of bilateral communication prevented the coordination of traffic between the two aircraft.
- Improper flight planning by the pilot of the PT-DAD, who likely failed to follow standard traffic patterns, contributed to the collision.
- Inadequate organizational culture at the flying club, which allowed the instructor to fly with inoperable essential equipment and permitted the operation of an aircraft with expired legal documentation.
- Failure of supervision by the aerodrome authorities and the flying club management, which failed to monitor or report the use of expired licenses and unairworthy aircraft.