What happened
USAir flight 4/5, operating a Fokker F-28, experienced a series of delays during its scheduled service from Jacksonville to New York. Initial delays were caused by inclement weather near LaGuardia and the removal of passenger luggage. After arriving at LaGuardia, the aircraft underwent de-icing procedures using Type I fluid. A mechanical failure of a de-icing truck caused a further delay in the pushback process.
During the taxi phase, the crew prepared for departure using contaminated runway procedures, which included a reduced V1 speed of 110 knots and a flap setting of 18 degrees. The captain utilized an empty coffee cup on the flap handle as a visual reminder to keep the flaps up during taxi. While the first officer inspected the right wing with the wing inspection light, no additional contamination was noted, and a third de-icing was not performed.
The aircraft was cleared for takeoff from runway 13 at 21:34:51. Following the rotation callout, the nose landing gear lifted off the runway. Roughly 4.8 seconds after rotation, the crew experienced six consecutive stall warnings via the stick shaker. The aircraft began a left-hand roll, prompting the crew to use right rudder to steer the plane away from the water. The crew attempted to maintain a flat attitude for impact, but the aircraft eventually came to rest partially inverted at the edge of Flushing Bay, with the cockpit and fuselage partially submerged. Small fires were observed in the wreckage and on the water following the impact.
Findings
- The aircraft was operating under contaminated runway procedures.
- The crew experienced a sudden stall during the takeoff roll.