B763, en-route, east southeast of Houston TX USA, 2019
B763, en-route, east southeast of Houston TX USA, 2019
On 23 February 2019, a Boeing 767-300 transitioned suddenly from a normal descent towards Houston into a steep dive and high speed terrain impact followed. The Investigation found that after neither pilot had noticed the First Officer’s inadvertent selection of go around mode during automated flight, the First Officer had then very quickly responded with an increasingly severe manual pitch-down, possibly influenced by a somatogravic illusion. He was found to have had a series of short air carrier employments terminating after failure to complete training, had deliberately and repeatedly sought to conceal this history and lacked sufficient aptitude and competency.
Description
On 23 February 2019, the crew of a Boeing 767-300 (N1217A) being operated by Atlas Air on a scheduled cargo flight for Amazon from Miami to Houston in day IMC with one non-revenue passenger on board lost control of their aircraft passing around 6000 feet during descent and it crashed into shallow water and was destroyed, killing the three occupants: the operating crew and a positioning off duty pilot who had been occupying a supernumerary seat in the flight deck.
Investigation
An Investigation into the accident was carried out by the NTSB. The FDR and CVR were located and recovered and their data were successfully downloaded and of assistance to the Investigation.
The Flight Crew
The 60 year-old Captain had a total of 11,172 flying hours experience which included 1,252 hours on type of which 157 hours were in command. After joining Atlas Air as a 767 First Officer in 2015, he had failed to complete type training to a standard which was considered adequate to take the type rating check ride but after remedial training had taken and passed it. He had then been placed in the Pilot Proficiency Watch Program (PWP) and remained within it for 15 months. Eighteen months after this, he successfully upgraded to 767 Captain and had subsequently successfully completed his first recurrent training on type two weeks prior to the accident.
The 44 year-old First Officer had a total of 5,073 flying hours experience which included 520 hours on type. He had joined Atlas Air as a 767 First Officer in July 2017 and commenced initial type training. He had required additional remedial training prior to taking and passing his oral type rating examination and further remedial training before achieving the standard required during fixed base simulator training to begin full flight simulator training for the type rating. He subsequently failed his practical 767 type rating examination due to “unsatisfactory performance in CRM, TEM, non precision approaches, steep turns, and judgment”. During an interview conducted as part of the Investigation, the Examiner who failed him stated that the First Officer “was very nervous, had very low situational awareness, overcontrolled the airplane, did not work well with the other pilot, omitted an emergency checklist during an abnormal event and exceeded a flap speed”. The Examiner also said that the First Officer had “not been thinking ahead and (that) when he realised that he needed to do something, he often did something inappropriate, like push the wrong button”. He added that the First Officer’s performance was so poor that he had wondered if he would be able to “mentally recover” enough to complete the course, however, after further remedial training, he had done so. His subsequent initial line training and recurrent checks were completed without further problems.
What Happened
No evidence was found that any aspect of the airworthiness or loading of the aircraft played any part in the loss of control which led to the accident. No evidence was found that the performance of either of the pilots involved was impaired by a lack of physical fitness to fly but “there was insufficient information to determine whether they were fatigued at the time of the accident”.
It was established that the First Officer had been acting as PF for the flight. As the descent towards Houston continued, FDR data showed that the aircraft had been descending normally at a pitch attitude of around 1° nose down with the AP and A/T engaged.
With the flight about 73 miles southeast of Houston and having just passed through 18,000 feet, the Captain checked in with the Houston Terminal Radar Control (TRACON). A few minutes later, the controller advised of an area of variable precipitation about 35 miles ahead and that they could expect vectors to navigate around it. Just after this exchange, the First Officer was recorded as saying “okay - I just had a…,” before temporarily transferring PF duties to the Captain. Whilst acting as PM, the First Officer confirmed to ATC that the flight would like vectors to take it west of the weather and acknowledged the re-clearance to 3000 feet QNH, to be conducted expeditiously due to potentially conflicting outbound traffic so as the descent continued, the speed brakes were extended. The controller then advised the flight to turn left onto 270°, which the Captain acknowledged before transferring PF duties back to the First Officer.
Just under a minute later, with the aircraft about 40 miles from Houston and passing 6,300 feet QNH, FDR data showed that the go-around mode had been activated. During the next six seconds, the engaged automation advanced the thrust levers and commanded an increase in the pitch attitude to about 4° nose up to initiate a climb. Neither pilot indicated that they had recognised the unintentional activation of the go-around mode and neither took action to disconnect the automation and the Captain “continued to receive and respond to routine ATC communications”.
Five seconds after the go-around mode activation, the speed brakes were retracted and the elevators began to move in response to manual control inputs commanding a steadily increasing amount of nose down pitch which caused the aircraft to enter a steep descent. It was noted that on the subject aircraft type, the automated flight systems could be overridden but such action would not disconnect the automation. After a further 8 seconds, the CVR recorded the First Officer saying “oh” followed in an elevated voice by “whoa… (where’s) my speed, my speed… we’re stalling” and a few seconds later by him exclaiming “stall”. The corresponding FDR data at this time determined that the airspeed and pitch attitude were not consistent with a stalled or near stalled condition and the stall warning system was not activated.
Almost immediately, after the “stall” callout by the First Officer, the Captain was recorded as asking “what’s goin’ on?” and three seconds later, the non revenue pilot passenger occupying the supernumerary crew seat called out “pull up”. This call was followed by the elevators moving in a manner consistent with manual control inputs to achieve a nose up pitch attitude. These nose up pitch control inputs continued for the remaining 7 seconds of the flight but failed to arrest the descent in time to prevent terrain impact. An annotated depiction of the final 32 seconds of the flight is depicted below.
The wreckage of the aircraft was scattered in a marshy area of Trinity Bay with most of it “immersed in or submerged beneath water up to a foot deep and buried beneath up to 10 feet of soft mud”. Lightweight cargo and composite airplane structure were found floating in the bay or along the shore up to 20 miles south of the initial impact point. More than 90% of the wreckage was recovered over a continuous seven week period and taken to a warehouse for examination.
Selected flight parameters and crew speech following go around mode activation. [Reproduced from the Official Report]
Why It Happened
Since the available evidence pointed to inadvertent activation of go around mode during descent, the way this was most likely to have happened was considered. Activating this mode required a pilot to push one of the go-around switches located on the outboard lower surface of each thrust lever. This process was confirmed by a ‘click’ sound on the CVR at the same time as the FDR recorded the mode change. Whilst it was not possible to be sure which go-around switch was pushed or how, it was determined that a likely scenario for its activation was that the First Officer probably had one hand on the (extended position) speed brake lever as a reminder to retract the speed brakes upon capture of the selected altitude (3000 feet) and the associated automatic increase in thrust in accordance with the applicable Atlas’ SOP for automated flight control. Simulator observations of pilots performing this scenario were found to show that a right seat PF holding the speed brake lever can place their left hand and wrist under the thrust levers and thereby “sufficiently close to the left go-around switch such that very little upward arm movement would be needed to make contact with the switch”. It was considered that the light turbulence which was recorded at the time of mode activation would have been sufficient to move a pilot’s arm this small distance and result in their wrist or wrist watch inadvertently moving the go around switch. This proposition is illustrated on the picture below.
Whilst the unexpected mode change associated with inadvertent selection of go-around mode and the abnormal altitude at which it had occurred would have been readily detectable by either pilot making an effective instrument scan and both the flight mode annunciator (FMA) and the EICAS would have displayed “GA” indications, neither pilot appeared to have appreciated the mode change. Had they done so, Atlas’ SOPs required that the response to unwanted operation of automated flight systems should be disconnection of the automation.
The position of a right seat pilot’s left hand and wrist whilst holding the speed brake lever. [Reproduced from the Official Report]
It was noted that although the First Officer had been slow to verbalise awareness that something unexpected had happened, the manual control inputs that began before this were considered to suggest that he had “sensed changes in the aircraft state and had begun to react without fully assessing the situation”. It was considered that manual retraction of the speed brakes 5 seconds after go-around mode activation was probably an instinctive action of the First Officer on feeling the increased load factor as the aircraft levelled off and hearing the increase in engine thrust which he was likely to have been anticipating when the aircraft reached its cleared altitude. In the absence of any apparent recognition by either pilot of any problem, it was concluded that when the aircraft’s acceleration and upward pitch began to increase about a second later - which would have resulted in an aft movement of the gravito-inertial force (GIF) vector detectable by the pilots, the manual forward control column inputs which were then applied were likely to have been made by the First Officer. It was noted that at the time this occurred, the Captain was in communication with ATC as part of his PM duties.
On the basis that human vestibular and somatosensory systems alone cannot distinguish between acceleration forces due to gravity and those resulting from manoeuvring of an aircraft, it was surmised that the First Officer’s pitch down control movement when confused as to the unexpected situation could plausibly be attributed to somatogravic illusion of a pitch up to which the only defence is reliance on the aircraft instruments.
About fifteen seconds after the go-around mode activation, FDR data showed that after initially confining his attention to communications and thereby not monitoring the aircraft state, the Captain had belatedly reacted to the dive by taking hold of his control column and pulling back against the First Officer’s continued nose down control input. This resulted in the elevator system control column override mechanism splitting the positions of the elevators on each side. FDR data showed that “these opposing elevator control forces continued for about 10 seconds” during which the dive became steeper.
Available weather information showed that the aircraft would have emerged from cloud at around 3,000 feet QNH at which point, FDR data showed that both elevators began to move concurrently in the nose-up direction, reaching full nose up and then remaining there until impact.
It was considered that the Captain’s failure to take over full control or disconnect either the AP or the A/T indicated that he had not been able to fully process the aircraft’s energy state, its automation status or the reason for the First Officer’s actions in the time available. He had thus enabled the First Officer to continue to force the aircraft into a steepening dive until "the situation was unrecoverable”.
The First Officer
The First Officer’s career history was examined to see if his unacceptable response to the unexpected change of automated flight mode might have any bearing on it. It was found that he had repeatedly submitted “incomplete and inaccurate information about his employment history on resumes and applications” and that these represented “deliberate attempts to conceal his history of performance deficiencies” and had “deprived Atlas Air and at least one other former employer of the opportunity to fully evaluate his aptitude and competency as a pilot”.
It was noted that between 2008 and 2017, he had been employed as a First Officer at a succession of regional air carriers. He had been employed as an Embraer 120 First Officer between 2008 and 2010 and again between 2013 and 2014. In 2011, he had failed to complete a DHC-8 type rating (and resigned) and in 2012 he had failed to complete a CRJ type rating (and resigned). Completion of an Embraer 145 type rating in 2014 was followed by failed line check (and resignation). In 2015, he had obtained an Embraer 175 type rating with Mesa Airlines before failing in an attempt to upgrade to Captain after two years as a First Officer and resigning.
This long history of training performance difficulties was found to have been characterised by “a tendency to respond impulsively and inappropriately when faced with an unexpected event” during training at multiple employers which suggested a consistent “inability to remain calm during stressful situations, a tendency that may have exacerbated his aptitude-related performance difficulties”.
Overall, it was concluded that “although compelling sensory illusions, stress, and startle response can adversely affect the performance of any pilot, the First Officer had fundamental weaknesses in his flying aptitude and stress response that further degraded his ability to accurately assess the airplane’s state and respond with appropriate procedures after the inadvertent activation of the go-around mode”.
Pilot Recruitment Processes
It was found that Atlas Air’s reliance on the use by their human resources personnel of “designated agents” to review the background records of applicants for pilot jobs and thereby identify any significant concerns was an ineffective process and had led directly to “the company’s failure to evaluate the First Officer’s unsuccessful attempt to upgrade to captain at his previous employer”. It was more generally observed that operators who “rely on designated agents or human resources personnel for initial review of records obtained under the Pilot Records Improvement Act should include flight operations subject matter experts early in the records review process”.
It was also concluded that “the manual process by which Pilot Records Improvement Act records are obtained” could easily result in the assessment of a prospective pilot employee’s history not obtaining all background records for a pilot who has failed to disclose a previous employer due to either wilful deception or, having resigned before successfully completing the initial aircraft type training required to be “considered fully employed”.
In respect of the situation generally, it was concluded that “had the FAA met the deadline and complied with the requirements for implementing the pilot records database (PRD) as stated in Section 203 of the Airline Safety and Federal Aviation Administration Extension Act of 2010, the PRD would have provided hiring employers relevant information about the First Officer’s employment history and training performance deficiencies”.
The Probable Cause of the accident was determined as “the inappropriate response by the First Officer (acting) as the PF to an inadvertent activation of the go-around mode, which led to his spatial disorientation and nose-down control inputs that placed the airplane in a steep descent from which the crew did not recover".
Three Contributory Factors were also identified as:
- the Captain’s failure to adequately monitor the airplane’s flight path and assume positive control of the airplane to effectively intervene.
- Systemic deficiencies in the aviation industry’s selection and performance measurement practices, which failed to address the First Officer’s aptitude-related deficiencies and maladaptive stress response.
- The Federal Aviation Administration’s failure to implement the Pilot Records Database in a sufficiently robust and timely manner.
Safety Action taken by Atlas Air after the accident was noted to have included:
- revisions to its interview process for new pilots to include a telephone screening interview where questions are asked to gauge credibility and consistency in an applicant’s answers during formal interview.
- the addition of a pilot logbook review to the interview process so as to obtain a better picture of the applicant’s overall career trajectory.
- the addition of an additional level of review of each candidate’s Pilot Records Improvement Act (PRIA) records by a member of the flight operations team to provide an additional technical perspective to its candidate vetting process.
- the formulation of a Standard Operating Procedure dedicated solely to pilot hiring.
A total of 6 new Safety Recommendations were made as a result of the Investigation as follows:
- that the Federal Aviation Administration inform Title 14 Code of Federal Regulations Part 119 certificate holders, air tour operators, fractional ownership programs, corporate flight departments, and government entities conducting public aircraft operations about the hiring process vulnerabilities identified in this accident, and revise Advisory Circular (AC) 120-68H, ‘Pilot Records Improvement Act and Pilot Records Database’ to emphasise that operators should include flight operations subject matter experts early in the records review process and ensure that significant training issues are identified and fully evaluated. [A-20-33]
- that the Federal Aviation Administration implement the Pilot Records Database and ensure that it includes all industry records for all training started by a pilot as part of the employment process for any Title 14 Code of Federal Regulations Part 119 certificate holder, air tour operator, fractional ownership program, corporate flight department, or governmental entity conducting public aircraft operations regardless of the pilot’s employment status and whether the training was completed. [A-20-34]
- that the Federal Aviation Administration ensure that industry records maintained in the Pilot Records Database are searchable by a pilot’s certificate number to enable a hiring operator to obtain all background records for a pilot reported by all previous employers. [A-20-35]
- that the Federal Aviation Administration establish a confidential voluntary data clearing house of de-identified pilot selection data that can be used to conduct studies useful for identifying effective, scientifically-based pilot selection strategies. This program should be modelled after programs like the Aviation Safety Information Analysis and Sharing (ASIAS) and Flight Operations Quality Assurance (FOQA). [A-20-36]
- that the Federal Aviation Administration issue a safety alert for operators to inform pilots and operators of Boeing 767- and 757-series airplanes about the circumstances of this accident and alert them that, due to the close proximity of the speed brake lever to the left go-around mode switch, it is possible to inadvertently activate the go-around mode when manipulating or holding the speed brake lever as a result of unintended contact between the hand or wrist and the go-around switch. [A-20-37]
- that the Federal Aviation Administration convene a panel of aircraft performance, human factors, and aircraft operations experts to study the benefits and risks of adapting military automatic ground collision avoidance system technology for use in civil transport-category airplanes and make public a report on the committee’s findings. [A-20-38]
Six Previously Issued Safety Recommendations, four which remain ‘Open’ because the response received has been deemed ‘Unacceptable’ and two for which the response has not yet been classified and were also formally reiterated as a result of this Investigation. They are as follows:
- that the Federal Aviation Administration require all Part 121 and 135 air carriers to obtain any notices of disapproval for flight checks for certificates and ratings for all pilot applicants and evaluate this information before making a hiring decision. [A-05-1] Classified ‘Open - Unacceptable Response’
- that the Federal Aviation Administration require 14 Code of Federal Regulations Part 121, 135, and 91K operators to document and retain electronic and/or paper records of pilot training and checking events in sufficient detail so that the carrier and its Principal Operations Inspector can fully assess a pilot’s entire training performance. [A-10-17] Classified ‘Open - Unacceptable Response’
- that the Federal Aviation Administration require 14 Code of Federal Regulations Part 121, 135, and 91K operators to provide the training records requested in Safety Recommendation A-10-17 to hiring employers to fulfil their requirement under the Pilot Records Improvement Act. [A-10-19] Classified ‘Open - Unacceptable Response’
- that the Federal Aviation Administration develop a process for verifying, validating, auditing, and amending pilot training records at 14 Code of Federal Regulations Part 121, 135, and 91K operators to guarantee the accuracy and completeness of the records. [A-10-20] Classified ‘Open - Unacceptable Response’
- that the Federal Aviation Administration require that all existing aircraft operated under Title 14 Code of Federal Regulations (CFR) Part 121 or 135 and currently required to have a cockpit voice recorder and a flight data recorder be retrofitted with a crash-protected cockpit image recording system compliant with Technical Standards Order TSO-C176a, “Cockpit Image Recorder Equipment” or equivalent (and) the image recorder should be equipped with an independent power source consistent with that required for cockpit voice recorders in 14 CFR 25.1457. [A-15-7] Response Not Yet Classified
- that the Federal Aviation Administration require that all newly manufactured aircraft operated under Title 14 Code of Federal Regulations (CFR) Part 121 or 135 and required to have a cockpit voice recorder and a flight data recorder also be equipped with a crash-protected cockpit image recording system compliant with TSO-C176a, “Cockpit Image Recorder Equipment”, or equivalent (and that) this image recorder should be equipped with an independent power source consistent with that required for cockpit voice recorders in 14 CFR 25.1457. [A-15-8] Response Not Yet Classified
The Final Report of the Investigation was dated and adopted on 14 July 2020 and subsequently published on 4 August 2020.