What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
After interviews and visual inspection of the tire markings made by the aircraft during the excursion, it is evident that the aircraft departed the runway due to mismanagement of flight controls. The markings on the runway show that the nose wheel was in contact with ground with the left main tire in the air for more than 1,000 feet. The left main did not contact the ground until the aircraft was already completely off the runway. This is consistent with interviews stating that the left main tire was in the air with the pilot input of full right aileron early in the landing roll.
The result of full right aileron combined with gusty winds, a ten degree wing flap deflection on touchdown and the inadequate use of back pressure on the yoke caused the aircraft weight to shift forward onto the nose wheel thus resulting in forces similar to those encountered with a ground loop. Although the high winds played a factor, if the pilot would not have used excessive aileron control input, the weight of the aircraft would not have been transferred to the nose wheel but instead would have remained on the main tires thus eliminating the out of control ground loop tendency that he encountered that is specific to this aircraft.
The PIC (captain) was the pilot flying and had indicated that fatigue was not a factor. Company time and duty logs show that the airman did not fly or was on duty the day prior.
There was no indication of abnormal maneuvering to the traffic pattern due to other air traffic or ATC instructions and the final approach path and speed was normal.
The PIC identified the gusty conditions as potential risk and mitigated the risk by utilizing an alternate flap setting - more favorable to windy conditions.
The facts gathered during the investigation indicated that the conditions for that time/day was within the aircraft's operating limitations.
The PIC does not have any prior accident/incident or enforcement history to indicate a trend or issue with airman competency. The PIC has also recorded over 1800 hours in the DHC-6-200 without incident.
Recommendation: the PIC should receive additional ground and flight training with focus on crosswind correction technique and avoidance of excess control imputs on the DHC-6-300.
Corrective action: on 06/01/2017, the airman was provided additional ground and flight training on the specific make/model aircraft (DHC-6-300) and was found satisfactory by the company check airman.
As the FAA filed it
AFTER INTERVIEWS AND VISUAL INSPECTION OF THE TIRE MARKINGS MADE BY THE AIRCRAFT DURING THE EXCURSION, IT IS EVIDENT THAT THE AIRCRAFT DEPARTED THE RUNWAY DUE TO MISMANAGEMENT OF FLIGHT CONTROLS. THE MARKINGS ON THE RUNWAY SHOW THAT THE NOSE WHEEL WAS IN CONTACT WITH GROUND WITH THE LEFT MAIN TIRE IN THE AIR FOR MORE THAN 1,000 FEET. THE LEFT MAIN DID NOT CONTACT THE GROUND UNTIL THE AIRCRAFT WAS ALREADY COMPLETELY OFF THE RUNWAY. THIS IS CONSISTENT WITH INTERVIEWS STATING THAT THE LEFT MAIN TIRE WAS IN THE AIR WITH THE PILOT INPUT OF FULL RIGHT AILERON EARLY IN THE LANDING ROLL.
THE RESULT OF FULL RIGHT AILERON COMBINED WITH GUSTY WINDS, A TEN DEGREE WING FLAP DEFLECTION ON TOUCHDOWN AND THE INADEQUATE USE OF BACK PRESSURE ON THE YOKE CAUSED THE AIRCRAFT WEIGHT TO SHIFT FORWARD ONTO THE NOSE WHEEL THUS RESULTING IN FORCES SIMILAR TO THOSE ENCOUNTERED WITH A GROUND LOOP. ALTHOUGH THE HIGH WINDS PLAYED A FACTOR, IF THE PILOT WOULD NOT HAVE USED EXCESSIVE AILERON CONTROL INPUT, THE WEIGHT OF THE AIRCRAFT WOULD NOT HAVE BEEN TRANSFERRED TO THE NOSE WHEEL BUT INSTEAD WOULD HAVE REMAINED ON THE MAIN TIRES THUS ELIMINATING THE OUT OF CONTROL GROUND LOOP TENDENCY THAT HE ENCOUNTERED THAT IS SPECIFIC TO THIS AIRCRAFT.
THE PIC (CAPTAIN) WAS THE PILOT FLYING AND HAD INDICATED THAT FATIGUE WAS NOT A FACTOR. COMPANY TIME AND DUTY LOGS SHOW THAT THE AIRMAN DID NOT FLY OR WAS ON DUTY THE DAY PRIOR.
THERE WAS NO INDICATION OF ABNORMAL MANEUVERING TO THE TRAFFIC PATTERN DUE TO OTHER AIR TRAFFIC OR ATC INSTRUCTIONS AND THE FINAL APPROACH PATH AND SPEED WAS NORMAL.
THE PIC IDENTIFIED THE GUSTY CONDITIONS AS POTENTIAL RISK AND MITIGATED THE RISK BY UTILIZING AN ALTERNATE FLAP SETTING - MORE FAVORABLE TO WINDY CONDITIONS.
THE FACTS GATHERED DURING THE INVESTIGATION INDICATED THAT THE CONDITIONS FOR THAT TIME/DAY WAS WITHIN THE AIRCRAFT'S OPERATING LIMITATIONS.
THE PIC DOES NOT HAVE ANY PRIOR ACCIDENT/INCIDENT OR ENFORCEMENT HISTORY TO INDICATE A TREND OR ISSUE WITH AIRMAN COMPETENCY. THE PIC HAS ALSO RECORDED OVER 1800 HOURS IN THE DHC-6-200 WITHOUT INCIDENT.
RECOMMENDATION: THE PIC SHOULD RECEIVE ADDITIONAL GROUND AND FLIGHT TRAINING WITH FOCUS ON CROSSWIND CORRECTION TECHNIQUE AND AVOIDANCE OF EXCESS CONTROL IMPUTS ON THE DHC-6-300.
CORRECTIVE ACTION: ON 06/01/2017, THE AIRMAN WAS PROVIDED ADDITIONAL GROUND AND FLIGHT TRAINING ON THE SPECIFIC MAKE/MODEL AIRCRAFT (DHC-6-300) AND WAS FOUND SATISFACTORY BY THE COMPANY CHECK AIRMAN.
Other reports on N189GC · 2
Matched to the same aircraft by N-number and date.