What happened
On January 22, 2004, an EMB-810C operated by Sete Táxi Aéreo departed Imperatriz, MA, bound for Belém, PA, transporting bank mail. During the flight, the aircraft experienced an instantaneous loss of power in the right engine while cruising at 9,000 feet.
The pilot, observing the declining light due to sunset and the inability to maintain level flight, decided to perform an emergency landing. The aircraft descended into a cleared area at Fazenda Espírito Santo, in Ulianópolis, PA. During the descent, the right wing struck a 5.5-meter stump, followed by the left horizontal stabilizer striking another stump. The aircraft eventually struck the ground, with the landing gear collapsing upon impact. The two crew members sustained minor injuries, but the aircraft suffered severe damage to the wings, fuselage, engines, and propellers.
The investigation
CENIPA investigators examined the engine and fuel systems, discovering that a fuel flow pressure tube (P/N 37343–32) had ruptured. The investigation revealed that the tube showed signs of fatigue caused by improper maintenance; specifically, dents and nicks were found that likely resulted from the use of pliers or a vise to force the component into alignment during installation.
Investigators also found that the aircraft was operating with an overdue 50-hour inspection. Furthermore, the crew had noted a drop in fuel flow during a previous flight leg that morning, but after a ground check by a mechanic in Imperatric, the aircraft was cleared for flight. The investigation also noted that the crew did not feather the propeller of the failed engine, which created significant drag and prevented the aircraft from maintaining altitude.
Findings
- Improper maintenance practices caused fatigue and the subsequent rupture of the fuel pressure tube.
- The pilot failed to feather the propeller of the failed engine, which generated excessive drag and made single-engine flight impossible.
- The aircraft was operating with an expired 50-hour maintenance inspection.
- There was a lack of proper supervision regarding weight and balance, as the cargo was not weighed and the takeoff weight was estimated, potentially exceeding maximum limits by 50 kg.
- The crew's decision to attempt to maintain altitude without feathering the propeller was based on a misunderstanding of the aircraft's performance capabilities in a single-engine configuration.