What happened
On April 5, 2014, a Pawnee Brave PA 36-375, registration RP-R3100, was conducting agricultural spraying operations over the Delta Farms banana plantation in Davao Del Norte. After completing its fourth flight mission of the day, the pilot began returning to the FADI Airstrip. During this transit, the pilot decided to deviate from the established flight plan to perform a low-level pass over the Mabantually-Katipunan Dam.
While flying at an altitude of approximately 50 to 60 feet AGL and a speed of 100 kph, the aircraft's propeller struck three layers of electric power lines belonging to DANECO. The impact caused electrical sparks and severe vibrations, leading to a sudden increase in the rate of descent. The pilot executed an emergency forced landing in a nearby banana field. Although the pilot successfully performed engine shutdown procedures before touchdown, the aircraft struck a large dead ipil-ipil tree during the landing. The pilot escaped the wreckage unharmed.
The investigation
The AAIIB investigation focused on the pilot's decision to deviate from the authorized area of operations and the visibility of the hazards encountered. Investigators examined the flight path, the nature of the electrical strike, and the environmental conditions at the dam site. The inquiry also reviewed the oversight responsibilities of the operator, Lapanday Food Corporation, regarding the monitoring of flight missions.
Findings
- The primary cause of the accident was the pilot's failure to maintain aircraft control after striking obscured electrical power lines due to a misjudged vision illusion.
- The pilot failed to identify environmental hazards that were blending with the surrounding vegetation, which obstructed his line of sight.
- The pilot's decision to intentionally divert the aircraft outside of the authorized flight itinerary was a significant contributing factor, potentially driven by overconfidence or complacency.
- A supervisory lapse by Lapanday Food Corporation was identified, as the company failed to adequately monitor and control aircraft operations during spraying missions.
Safety action
- The AAIIB recommended that the CAAP Flight Standards Inspectorate Service (FSIS) strictly enforce proficiency training focused on emergency conditions for agricultural pilots.
- Recommendations were made for FSIS to implement provisions for companies to enforce disciplinary measures regarding professional conduct and decorum.
- The board advised that companies must enhance the monitoring and supervision of flight missions to prevent accidents.
- A recommendation was issued for CAAP to review and update procedures for the Philippine Banana Grower and Export Association (PBGEA) to ensure higher safety standards during agricultural spraying operations.