What happened
On January 24, 1998, an Air Tractor AT-501W, registration N-1006T, departed St. John’s, Canada, on an export flight destined for Douala, Cameroon, with a planned technical stop in Santa Maria, Azores. The flight was intended to be a daylight VFR operation; however, the aircraft departed later than planned, placing the final stages of the flight into nighttime operations.
As the aircraft entered the Santa Maria Terminal Control Area (TMA), the pilot experienced significant difficulties establishing direct radio contact with Santa Maria Oceanic Control. Communication was only possible via a relay from another aircraft, RCH744 and RCH7448. During the flight, the pilot reported encountering rain and flying through clouds, yet the aircraft was not equipped for IFR operations.
In an attempt to assist, air traffic controllers directed the aircraft toward an alternate airport at Horta, Faial. During this period, the pilot's situational awareness was compromised by the combination of night, unknown terrain, and deteriorating weather. The aircraft eventually struck the ground at an altitude of approximately 725 meters near Pico Alto on the island of São Jorge. The pilot sustained fatal injuries, and the aircraft was a total loss.
The investigation
The GPIAAF investigation examined the flight planning, the aircraft's equipment, and the management of the flight by air traffic services. Investigators looked into the lack of direct VHF communication between the aircraft and Santa Maria Control, the reliance on a third-party aircraft for relaying instructions, and the decision-making process regarding the diversion to Horta. The investigation also reviewed the regulatory oversight by Canadian authorities regarding transatlantic inspections for general aviation aircraft.
Findings
- The pilot's inadequate flight planning was a primary factor, as the flight required IFR capabilities and specific qualifications for transoceanic operations that were not met.
- The aircraft lacked the necessary onboard navigation equipment for a transoceanic flight under adverse weather conditions.
- Air traffic services in Santa Maria faced significant challenges due to inconsistent VHF radio coverage and a lack of technical means to identify or position aircraft with reduced navigation capabilities.
- The decision to divert the aircraft to an unplanned alternate airport (Horta) introduced additional complexities into an already critical situation.
- The pilot's ability to maintain situational awareness was severely diminished by the combination of night operations, unfamiliar terrain, and degraded weather.