What happened
On February 5, 2011, a Sikorsky S-76A, registration PP-MBL, operated by Atlas Táxi Aéreo Ltda., departed Jacarepaguá Airport (SBJR) for an offshore mission to maritime platform SS-72 (9PCS). The flight was intended to transport cargo and personnel. After landing at the platform, the crew exchanged six passengers for ten new passengers and departed for the return trip to SBJR without refueling.
During the return leg, the crew requested a direct approach to runway 02, which was opposite to the active runway. The control tower initially denied this request due to existing traffic. Shortly after, the crew declared an emergency, citing technical issues, and were authorized to proceed with the direct approach. The helicopter landed at 17:41 UTC without further incident; however, the 'FUEL LOW' indicator lights for both fuel tanks were illuminated upon arrival.
There were no injuries to the two crew members or the ten passengers, and the aircraft sustained no damage.
The investigation
CENIPA's investigation focused on the fuel planning and the regulatory requirements for VFR operations under RBAC 135. The investigation established that the aircraft was operating at its maximum takeoff weight of 10,500 lb. To comply with safety regulations, the flight plan required enough fuel for the trip, plus an additional 10% of the planned flight time, plus a 20-minute reserve.
Based on the flight distance of 210 NM (round trip) and an estimated consumption rate, the minimum required fuel for the mission was calculated at 1,257 lb. However, the aircraft had been fueled with only 1,218 lb at the start of the mission. The investigation also noted that a headwind during the outbound leg likely increased fuel consumption beyond the initial estimates.
Findings
- The aircraft was fueled with an amount below the minimum required by regulation.
- Inadequate flight planning failed to provide a sufficient safety margin for environmental variables.
- The aircraft was operating at its maximum takeoff weight, which likely restricted the amount of fuel that could be loaded.
- Ineffective managerial supervision contributed to the use of insufficient fuel reserves.