What happened
On May 5, 2010, a Cessna F150L, registration CS-AOT, was performing a touch-and-go maneuver on runway 18 at Vise and Aerodrome. The aircraft, operated by Aeroclube de Leiria, was occupied by a flight instructor and a student pilot. During the landing roll, the instructor spotted a Socata Tobago 200, registration CS-DEF, landing on the opposite runway (runway 36).
In an attempt to avoid a mid-air collision, the instructor took control of the Cessna F150L and applied full power to lift the aircraft off the ground. However, the aircraft failed to gain sufficient altitude, entered a stall, and impacted the ground, subsequently flipping onto its back. The two occupants of the Cessna F150L sustained two minor injuries.
The investigation
The GPIAAF investigation focused on the communication and procedural discrepancies between the two aircraft. The investigation established that the two crews were operating on different radio frequencies. The crew of CS-AOT was using frequency 122.7 MHz, while the student pilot of the CS-DEF was using 122.3 MHz. Because they were not on the same frequency, their "blind transmissions" (broadcasts intended to alert others of their presence) were not heard by the other aircraft.
Furthermore, the investigation found that the student pilot of the CS-DEF had not followed the local VFR manual procedures, which required a fly-over of the aerodrome to check wind conditions and operational status. The investigation also noted that the student pilot was using outdated aeronautical publications, as they were still referring to the runway as runway 01 instead of the updated runway 36.
Findings
- The primary cause was the loss of control of the Cessna F150L during an evasive maneuver intended to avoid a collision.
- The two aircraft were performing simultaneous landings on the same runway in opposite directions.
- The pilots were unable to communicate because they were monitoring different radio frequencies.
- The student pilot of the CS-DEF failed to perform the required overhead pass to verify local conditions.
- The runway gradient of 0.7% limited the pilots' field of vision during the landing phase.
Safety action
- The GPIAAF recommended that the Director of Viseu Aerodrome establish formal "blind transmission" procedures and request their inclusion in the VFR Manual.
- A recommendation was made to the National Civil Aviation Authority (INAC) to implement standardized "blind transmission" procedures at all national aerodromes that are not certified for AFIS services.