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Rejected takeoff above decision speed caused Antonov An-74 runway overrun accident at São Tomé
9 December 2018

Rejected takeoff above decision speed caused Antonov An-74 runway overrun accident at São Tomé

Finnish probe into ERJ-190 incident finds serious deficiencies in post-evacuation transportation

NTSC Indonesia publishes preliminary report on JT610 Boeing 737 MAX 8 accident

NTSC Indonesia published a preliminary report on the Lion Air B737 MAX 8 accident of October 29, showing the flight crew was struggling to maintain control after takeoff.

Lion Air flight 610 crashed into the sea shortly after takeoff from Jakarta-Soekarno-Hatta International Airport, Indonesia, killing all 189 on board.

According to the preliminary report, the Aircraft Flight Maintenance Log (AFML) recorded that since October 26 until the occurrence date several problems occurred related to airspeed and altitude flags that appeared on the captain’s (left) Primary Flight Display (PFD) on three occasions, SPEED TRIM FAIL light illumination and MACH TRIM FAIL light illumination that occurred twice.
Several attempts were made by engineers to rectify these issues. The day before the accident the Angle of Attack (AoA) sensor was replaced by engineers at Denpasar Airport.

The flight from Denpasar to Jakarta was the flight prior to JT610.  During rotation, the stick shaker activated and an IAS DISAGREE warning showed on the captain’s PFD at 400 feet. The flight was handled by the copilot as it was determined that the captain’s PFD was unreliable. The flight crew moved the STAB TRIM (stabilizer trim) switch to CUT OUT due to three automatic nosedown trim occurrences. The crew worked checklists and continued the flight to CGK.
Based on the crew’s entry in the AFML, the engineer at Jakarta flushed the left Pitot Air Data Module (ADM) and static ADM to rectify the reported IAS and ALT disagree and cleaned the electrical connector plug of the elevator feel computer.  The aircraft was subsequently released to carry out flight JT610.
During takeoff from Jakarta, the DFDR recorded a difference between left and right Angle of Attack of about 20° which continued until the end of the recording. During rotation of the aircraft, the left control column stick shaker activated and continued for most of the flight.
After the flaps were retracted, the FDR recorded automatic aircraft nose down (AND) trim for 10 seconds followed by flight crew commanded aircraft nose up (ANU) trim. Automatic AND trim briefly stopped when the flaps were temporarily extended to 5.
In their communications with air traffic control, the flight crew asked the controller to confirm the altitude of the aircraft and later also asked the speed as shown on the controller radar display. The copilot reported experiencing a “flight control problem” and that they were flying the aircraft manually.
Last radio contact was at 06:31 local time when the captain requested the arrival controller to block altitude 3,000 feet above and below for traffic avoidance. The controller asked what altitude the pilot wanted, to which the captain responded “five thou”. The controller approved the pilot request. The FDR stopped recording within twenty seconds of the pilot’s response.
More information:

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NTSB: fatal Metroliner crash due loss of control after pilot continued into adverse weather

Metroliner cargo flight turns ugly when loose screwdriver hit propeller during takeoff

FBI completes investigation into August 2018 crash of stolen DHC-8 near Seattle

The FBI has completed its investigation of the unauthorized flight of a Horizon Air DHC-8-Q400 aircraft that occurred on August 10, 2018, from Seattle-Tacoma International Airport in Washington, USA. 

Evidence collected during the course of the investigation indicates a 28-year old ground-service agent piloted the aircraft and that the final descent to the ground was intentional. Extensive investigative activity failed to reveal any additional subject(s) involved in the planning or execution of the unauthorized flight.

Flight Data Recorder (FDR) data indicated a significant sideslip on the airplane during the final minute of flight, but the airplane appeared to have remained in control, and the final descent to the ground appeared to have been intentional. If the pilot had wanted to avoid impact with the ground, the FBI stated, he had time and energy to pull the control column back, raise the nose, and initiate a climb. Instead, the controls remained in a position forward of neutral and moved further forward about six seconds prior to the end of the FDR data, which corresponded with the aircraft crash on Ketron Island, Washington, USA.

The Cockpit Voice Recorder (CVR) was recovered, but did not capture any significant sounds beyond the voice communications that the pilot conveyed over the cued microphone. He did not make any phone calls while in the cockpit of the aircraft or make any other statements that addressed his motive.

Interviews with work colleagues, friends, and family – and review of text messages exchanged with the pilot during the incident – did not identify any information that would suggest the theft of the aircraft was related to wider criminal activity or terrorist ideology, according to the FBI. Although investigators received information regarding his background, possible stressors, and personal life, no element provided a clear motivation for his actions.

The events of August 10, 2018, unfolded along this approximate timeline, all in Pacific Daylight Saving Time:

  • 2:36 p.m. – arrival at Port of Seattle-operated employee security checkpoint at Seattle-Tacoma International Airport for his work shift
  • 2:38 p.m. – cleared through employee security checkpoint screening, without any anomalies
  • 7:15 p.m. – arrived in a tow vehicle at Cargo 1, at far north end of Sea-Tac airfield
  • 7:19 p.m. – climbs inside Horizon Air Q400 aircraft #N449QX
  • 7:22 p.m. – begins sequence to start aircraft, and propellers start turning
  • 7:27 p.m. – exits the plane and uses tow vehicle to turn aircraft nose toward the airfield
  • 7:28 p.m. – re-enters the plane
  • 7:32 p.m. – aircraft pulls away from its parked location
  • 7:33 p.m. – aircraft takes off from the airport
  • 8:46 p.m. – FDR data shows end of flight


Report: Embraer EMB-120 cargo plane misaligned take off from Amsterdam-Schiphol Airport