What happened
On April 1, 2018, at approximately 19:00 UTC, a Robinson R44 II helicopter, registration PP-WVR, crashed near Vila Nambuaçú, in the municipality of Rosário, Maranhão. The aircraft had departed from an improvised landing area in Lima Campos for a private transport flight to Heliponto Veja. The flight was carrying a pilot and three passengers.
During the flight, the crew established contact with São Luís Approach (APP-SL) approximately 30 nautical miles from the airport. However, shortly after confirming flight plan details, all communication with the aircraft was lost. The impact resulted in the total destruction of the aircraft and four fatalities (the pilot and three passengers).
The investigation
CENIPA's investigation focused on the structural integrity of the aircraft and the qualifications of the crew. Investigators examined the main rotor blades (part number C016-5) and discovered evidence of significant structural degradation. Specifically, corrosion was found between the blade core and the outer skin, which had caused the skin to delaminate.
While maintenance logs indicated that the blades had been inspected and approved for service in previous years, investigators found that a 2016 inspection had actually identified skin separation that was not approved for return to service. Furthermore, this specific maintenance finding had not been recorded in the aircraft's logbooks. The investigation also noted that the pilot was operating with an expired medical certificate and an expired helicopter rating. Additionally, the flight plan was filed using the CANAC (personnel identification) of a different crew member.
Findings
- Corrosion between the main rotor blade core and the skin was present prior to the accident, leading to structural failure.
- The main rotor blades required replacement according to Airworthiness Directive 2014-20-16, but the aircraft was operating with blades that had documented, unrecorded skin separation.
- The pilot was not qualified to operate the aircraft, as both the medical certificate and the helicopter rating were expired.
- Maintenance records for the airframe and engine were not up to date.
- Adverse meteorological conditions were present near São Luís at the time of the occurrence.
- The flight plan was filed using incorrect crew identification data.