Massachusetts

The pilot was transporting six passengers on a scheduled revenue flight in instrument meteorological conditions. The pilot familiarized himself with the weather conditions before departure and surmised that he would be executing the instrument landing system (ILS) instrument approach for the landing runway at the destination airport. The operator prohibited approaches to runways less than 4,000 ft long if the tailwind component was 5 knots or more. The landing runway was 498 ft shorter than the operator-specified length. The pilot said he obtained the automated weather observing system (AWOS) data at least twice during the flight since he was required to obtain it before starting the instrument approach and then once again before he crossed the approach’s final-approach-fix (FAF). Though the pilot could not recall when he checked the AWOS, he said the conditions were within the airplane and company performance limits and he continued with the approach. A review of the wind data at the time he accepted the approach revealed the tailwind component was within limitations. As the airplane approached the FAF, wind speed increased, and the tailwind component ranged between 1 and 7 knots. Since the exact time the pilot checked the AWOS is unknown, it is possible that he obtained an observation when the tailwind component was within operator limits; however, between the time that the airplane crossed over the FAF and the time it landed, the tailwind component increased above 5 knots. The pilot said the approach was normal until he encountered a strong downdraft when the airplane was about 50 to 100 ft above the ground. He said that the approach became unstabilized and that he immediately executed a go-around; the airplane touched down briefly before becoming airborne again. The pilot said he was unable to establish a positive rate of climb and the airplane impacted trees off the end of the runway. The accident was captured on three airport surveillance cameras. A study of the video data revealed the airplane made a normal landing and touched down about 500 ft from the beginning of the runway. It was raining heavily at the time. The airplane rolled down the runway for about 21 seconds, and then took off again. The airplane entered a shallow climb, collided with trees, and caught on fire. All seven occupants were seriously injured and the airplane was destroyed.

The pilot reported that, while descending through clouds and beginning the instrument approach, some ice accumulated on the wings and he actuated the deice boots twice. The pilot saw the deice boots functioning normally on the wings and could not see the tail; however, the elevator began to shake, and he lost elevator control. The pilot applied forward pressure on the yoke and had to trim nose-down to avoid a stall. There were no cockpit caution indications and the pilot had disengaged the autopilot before descent. The airplane descended through the clouds and impacted a tree before coming to rest upright in a grass area. Postaccident examination of the wreckage, including component testing of the deice system, did not reveal any preimpact mechanical malfunctions. The flap jackscrew position suggested that the flaps were likely in transit between 0° and 10° flap extension at the time of impact. Review of radar data revealed that, during the 2 minutes before the accident, the airplane’s groundspeed averaged about 82 knots; or an approximate average airspeed of 94 knots when accounting for the winds aloft. Current weather observations and forecast weather products indicated that the airplane was likely operating in an area where moderate and potentially greater structural icing conditions prevailed, and where there was the potential for the presence of supercooled liquid droplets. Review of the pilot operating handbook for the airplane revealed that the minimum speed for flight in icing conditions was 130 knots indicated airspeed. It is likely that the pilot’s failure to maintain an appropriate speed for flight in icing conditions resulted in insufficient airflow over the ice contaminated elevator and the subsequent loss of elevator control.

The private pilot was conducting a local, personal flight. The pilot reported that he checked the weather conditions at three local airports before the flight but stated that he did not trust the wind reports. He added that he did not get a preflight weather briefing. Once at the destination airport, he conducted two go-arounds due to gusting wind conditions. During the third attempted landing, he made a steep approach at a normal approach speed and flared the airplane about midway down the 3,000-ft-long runway. The airplane floated down the runway for much longer than the pilot expected before touching down. Despite applying maximum braking, there was insufficient remaining runway to stop, and the airplane skidded off the runway, impacted trees, and subsequently caught fire, which resulted in substantial damage to the airframe. The wind conditions reported at an airport located about 13 miles away included a tailwind of 16 knots, gusting to 27 knots. Given the tailwind conditions reported at this airport and the pilot's description of the approach and landing, it is likely that the pilot conducted the approach to the runway in a tailwind that significantly increased the airplane's groundspeed, which resulted in a touchdown with insufficient runway remaining to stop the airplane, even with maximum braking.

The commercial pilot stated that, shortly after taking off for a cross-country, personal flight and while accelerating, he noticed high airplane nose-down control forces and that the airplane became increasingly difficult to control. He used manual trim to attempt to trim out the control forces and verified that the autopilot was not engaged; however, the nose-down tendency continued, and the pilot had trouble maintaining altitude. During the subsequent emergency landing, the airframe sustained substantial damage. Postaccident examination of the airplane revealed that the elevator trim push rod assembly was separated from the elevator trim tab actuator, and the end of the elevator trim push rod assembly was found wedged against the elevator's main spar. The elevator trim indicator in the cockpit was found in the nose-up stop position; however, the elevator trim tab was deflected 24° trailing edge up/airplane nose down (the maximum airplane nose-down setting is 6°). A drilled bolt was recovered from inside the right elevator; however, the associated washer, castellated nut, and cotter pin were not found. Examination of the bolt revealed that the threads were damaged and that the bolt hole on one of the clevis yoke halves exhibited deformation, consistent with the bolt separating. About 2 weeks before the accident, the pilot flew the airplane to a maintenance facility for an annual inspection. At that time, Airworthiness Directive (AD) 2016-07-24, which required installation of new hardware at both ends of the pushrod for the elevator trim tab, was overdue. While the airplane was in for the annual inspection, AD 2016-07-24 was superseded by AD 2016-17-08, which also required the installation of new hardware. The ADs were issued to prevent jamming of the elevator trim tab in a position outside the normal limits of travel due to the loss of the attachment hardware connecting the elevator trim tab actuator to the elevator trim tab push-pull rod, which could result in loss of airplane control. While in for the annual inspection, the airplane was stripped and painted, which would have required removal of the right elevator. Although the repair station personnel indicated that they did not disconnect the elevator trim pushrod from the elevator trim tab actuator when they painted the airplane, photographs taken of the airplane while it was undergoing inspection and painting revealed that the pushrod likely had been disconnected. The repair station owner reported that he reinstalled the right elevator and the elevator trim pushrod after the airplane was painted; however, he did not replace the hardware at either end of the pushrod as required by the ADs. Subsequently, the airplane was approved for return to service. After the annual inspection, no work, repairs, or adjustments were made to the elevator trim system. The airplane had accrued about 58 hours since the annual inspection at the time of the accident. Although reusing the self-locking nut might have resulted in it coming off by itself, the cotter pin should have prevented this from happening. Therefore, although the castellated self-locking nut, washer, and cotter pin normally used to secure the elevator trim pushrod at the elevator trim tab actuator were not found, given the evidence it is likely that the hardware, which was not the required hardware, was not properly secured at installation, which allowed it to separate in flight. It is also likely that the pushrod assembly then moved aft and jammed in a position well past the maximum nose-down trim setting, which rendered controlled flight impossible.