NTSB Identification: ERA12FA567
14 CFR Part 91: General Aviation
Accident occurred Tuesday, September 18, 2012 in Macon, GA
Probable Cause Approval Date: 06/23/2014
Aircraft: BEECH 400, registration: N428JD
Injuries: 2 Minor,1 Uninjured.
NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
The pilot was seated in the left seat and was the flying pilot. The pilots reported that prior to departure, there were no known mechanical malfunctions or abnormalities with the airplane, including the brakes, flaps, anti-skid, or thrust reversers. The copilot, who was the pilot monitoring, calculated a Vref speed of 108 knots for the landing weight. Postaccident analysis determined that a more precise Vref based on weight would have been 110 knots. Both pilots reported that they set their airspeed index bugs to 108 knots about 11 miles from the airport.
The pilot reported that the airplane touched down about 1,000 feet from the approach end of the runway. Both crewmembers reported that, although they used maximum thrust reversers, brakes, and ground spoilers, they could feel a “pulsation” in the brake system and that the airplane hydroplaned. The airplane overran the wet runway with standing water and came to rest 283 feet beyond the paved portion of the runway in a treed area off the airport.
Postaccident examination of the airspeed index bugs revealed that the pilot’s was set to 115 knots and that the copilot’s was set to 105 knots, which correlated with their calculated and reported V1 and V2 departure speeds. It is likely that they did not move the airspeed bugs during the approach to landing. Postaccident testing of the brake system components did not reveal any mechanical malfunctions or abnormalities that would have precluded normal operation.
Based on radar data, the airplane was likely 15 to 19 knots above the reference speed of 110 knots when it crossed the runway threshold. The data further revealed that the approach was flown with about a 4-degree glideslope approach angle instead of the recommended 3-degree glideslope angle. The pilots reported that the precision approach path indicator lights, which would have provided an approximate 3-degree approach, became inoperable shortly after activation. Although the touchdown location could not be accurately determined, given the approximate glideslope and the excessive speed, the airplane likely floated before touching down.
It is also likely that the pilots, familiar with landing at their home airport, which is configured with a grooved runway that mitigates wet runway conditions more effectively, relied on their past wet runway experience and failed to calculate their landing distance using the appropriate performance chart for the contaminated runway. Based on the airplane’s performance charts, on a contaminated runway, an airplane with a Vref of 110 knots would need a 4,800-foot runway; at Vref + 10 knots, the airplane would need 6,100 feet to land. The runway was 4,694 feet long. Hence, the lack of a clear understanding of the actual wet runway landing distance necessary to stop and the excessive approach speed resulted in the airplane crossing the approach end of the runway at a speed and flight profile unsuitable for the wet runway condition and without sufficient distance available to stop. Further, the pilots exhibited poor crew resource management by not using the appropriate chart for the contaminated runway, not recognizing the runway was too short based on the conditions, failing to reset their airspeed bugs before the approach, and not recognizing and addressing the excess approach speed.
The National Transportation Safety Board determines the probable cause(s) of this accident to be: The pilot’s failure to maintain proper airspeed, which resulted in the airplane touching down too fast on the wet runway with inadequate runway remaining to stop and a subsequent runway overrun. Contributing to the landing overrun were the flight crewmembers’ failure to correctly use the appropriate performance chart to calculate the runway required to stop on a contaminated runway and their general lack of proper crew resource management.
Full narrative available
Index for Sep2012 | Index of months