US Dash 8-100 Stalled and Dropped 5000 ft Over Alaska

US Dash 8-100 Stalled and Dropped 5000 ft Over Alaska (Era Aviation N886EA)

On 5 September 2012 Bombardier DHC-8-103 / Dash 8-100 N886EA, operated by Era Aviation as a Part 121 scheduled commercial flight with 12 passengers and 3 crewmembers onboard, stalled, rolled and made an uncontrolled descent when climbing through 12,000 feet.  The aircraft dropped 5,000 ft before the crew recovered full control of the aircraft.  The occupants were uninjured and the aircraft returned to Ted Stevens Anchorage International Airport (ANC), Alaska with minor damage.

Era Aviation Bombardier Dash 8-100 N886EA at Anchorage in August 2016 after the Operator was Renamed Ravn (Credit: Sunnya343 CC BY-SA 4.0

Era Aviation Bombardier Dash 8-100 N886EA at Anchorage in August 2016 after the Operator was Renamed Ravn Alaska (Credit: Sunnya343 CC BY-SA 4.0)

History of the Flight

The US National Transportation Safety Board (NTSB) explain in their safety investigation report (issued only on 8 July 2020, 94 months later and after the operator [by then Ravn Alaska] and its owner had gone bankrupt!):

The flight was cleared to a cruise altitude of 10,000 feet. Both pilots stated in interviews that the captain engaged the autopilot when the flight reached an altitude of about 1,000 feet agl. The captain stated that he engaged the indicated airspeed (IAS) button on the advisory display unit and set a climb speed of 150 to 160 knots. Between 7,000 and 8,000 feet, the airplane entered a cloud deck and began accumulating ice, and the captain turned on the de-icing equipment.

The crew say the system was working but only clearing ice from the propeller spinners not the airframe.  They requested ATC clearance to climb to up to 14,000 ft to avoid the icing.  This was granted.

While commencing the climb, the captain initially set 14,000 feet in the altitude alert controller. The captain stated that he engaged the IAS button when he initiated the climb out of 10,000 feet and that he did not use the vertical speed (VS) mode during the flight. He could not recall the position of the throttles during the climb from 10,000 feet, but he noted that he did not manipulate them once he initiated the climb.

Although the airplane was equipped with [orange] fast-slow type speed control indicators on each pilot’s attitude director indicator (ADI), neither pilot reported looking at it. According to flight data recorder (FDR) data, during the climb, the initial airspeed was 170 knots, the climb rate was 850 feet/minute, and the engine power was not increased. The data showed a steady decrease in airspeed and a steady increase in altitude and pitch attitude for the duration of the climb.

The captain stated that, during the climb, he was monitoring the icing indications. The first officer stated that he was monitoring the de-icing panel; looking outside to make sure the de-icing boots were inflating and deflating in the proper sequence; and looking at the propeller spinners, windshield wipers, and windshield. The first officer said he was also getting ready to communicate with the arrival station and taking care of paperwork in preparation for landing.

Passing through about 11,500 feet, the flight began to emerge from the tops of the clouds, and the captain set the altitude alert controller to level at 12,000 feet.  As the airplane began to level off, it began to shudder and the flight crew attributed it to an unbalanced condition of the propellers due to the uneven shedding of ice.

This is when things developed rapidly:

According to FDR data, the airplane lost lift at 1041:18 as the airplane was climbing through 12,192 feet at an airspeed of 103 knots. The flight crew indicated that, shortly after, the shudder increased rapidly, the airplane rolled left, followed immediately by a pitch down. The FDR data showed that the left roll began at 1041:23 at an airspeed of 97 knots and reached a left bank of 47° in about 11 seconds.

According to both pilots, no stick shaker warning activated before the airplane rolled. Stick shaker activation was not a recorded parameter on the FDR.

Noticeably [emphasis added]:

After the airplane lost lift, the control column began to move back gradually from 3° to 8.5° over about 9 seconds increasing the pitch of the airplane to about 20° nose up. The autopilot remained on during this time. The captain opposed the left roll with control wheel input and the airplane recovered slightly before rolling further left to 55°.

The captain stated that he attempted to control the airplane by rolling it to wings level and pulling nose up, but he was unable to regain control. He added that he made a combination of control and power inputs, pushing the yoke and power forward and back as the airplane descended rapidly. FDR data indicated that the autopilot disconnected at 1041:26.7. At 1041:27 (about the same time the airplane reached its maximum altitude of 12,288 feet), the column was pulled back rapidly from 8.5° to 33° in 3 seconds.

The column was held aft at greater than 33° until 1041:43, at which time, the captain began to release the back pressure. The airplane pitch decreased from 20° nose up to 37° nose down during this time. FDR data further show that the captain did not attempt to push the column forward during the descent for another 7 seconds until 1041:50.

At 1042:04 the airplane reached its lowest altitude of 7,072 feet and began to level out and stabilize after descending more than 5,200 feet in about 37 seconds. The flight made a left 270° turn during the uncontrolled upset event.

N886EA dash 8 era alaska stall flight profile

FDR data shows the engines were set about 70% of maximum torque when the airplane leveled off at 10,000 feet where they remained until the upset event. After the left roll, the engine power was reduced to about 30% of maximum torque for about 10 seconds before being increased above 100% exceeding the torque limitations. The engine power was reduced to about 90% before the airplane reached its lowest altitude and leveled off before being increased again further above 100% than previously.

The flight crew declared an emergency with ATC…[and returned safely to ANC].

The NTSB Safety Investigation

The Weather

The airplane was equipped with an atmospheric sensor called, “Tropospheric Airborne Meteorological Data Reporting” (TAMDAR) system, which recorded a number of weather parameters, including wind, temperature, relative humidity, and icing. The TAMDAR data indicated that the airplane likely entered clouds about 9,800 feet based on the relative humidity of 90 percent and started picking up airframe ice with at least 0.5 millimeter accumulation before the icing sensor heating element came on. The cloud layer extended to 10,500 feet and was likely composed of liquid water droplets with a temperature of -11º C. The airplane was operating on top of the cloud layer when the upset occurred. The sensor also showed that, at 1039:01, the TAMDAR sensor detected some pitot static icing issues immediately before the upset and began reporting an unreliable airspeed. The chief scientist at the TAMDAR manufacturer noted the data indicated an encounter with light icing conditions.

The Aircraft Systems

The Dash 8-100 is equipped with a stall warning system.

During low-speed flight, the system’s lift transducers, one of which is located on the leading edge of each wing, transmit AOA information to their lift computers. The computers combine the AOA information with flaps position data and accelerometer inputs to provide the stall speed warning threshold. The computers activate the stick shakers whenever the threshold is reached to indicate an impending stall. The activation of the stick shaker cannot be changed to provide more protection when flying in icing conditions.  The stick shaker activation…is based on a correlation between a wing-mounted force transducer and the airplane’s AOA.

Curiously the NTSB state that:

Bombardier was unable to provide documentation of this correlation; therefore, it was not possible to determine when the stick shaker was set to activate. Due to a lack of FDR and cockpit voice recorder (CVR) evidence, the activation of the stick shaker could not be determined.

CVR Data

The CVR recording of the crucial part of the flight was found to have been overwritten.  The aircraft should have been upgraded by 7 April 2012 to have a 2 hour CVR capacity after an FAA rule change 4 years earlier.  The FAA Principal Avionics Inspector (PAI) for Era suggested that…

…significant turnover within the company of three Directors of Quality Control (DQC)s and twoDirectors of Maintenance (DOMs) since 2008 possibly allowed the new CVR regulations to “fall through the cracks”.

After being notified that the CVR installed on the incident aircraft did not meet the current regulatory standard, ERA reviewed the CVRs installed on their entire fleet and found that none of them recorded the required 2-hour duration. Era suspended flight operations until they could acquire the necessary supplemental type certificates and parts to bring the fleet into compliance. The DHC-8 fleet was grounded for about 5 days and the BE-1900 fleet was grounded about 3 days. After the installations were completed, the aircraft were returned to service.

Aircraft Performance Study and Flight Handling Analysis

The NTSB conducted an aircraft performance study to analyse the aircraft’s position and orientation throughout the 69 second loss of control event and determined the aircraft’s response to control inputs and external factors (such as icing). It used FDR data, TAMDAR instrumentation data, ATC communications and ATC radar data. The reconstructed timeline was as follows (note the typo in the final number):

N886EA dash 8 era alaska stall timeline

The calculated drag coefficient (Cd) of the incident flight was compared to the four previous flights recorded on the FDR:

N886EA dash 8 era alaska stall drag coefficient

Cd was increasing as the aircraft began climbing above 10,000 feet.  NTSB believe this is consistent ice build-up and while there may have been some ice accumulation at 10,000 ft, the icing likely worsened during the climb.

Because the airplane began to climb steadily without the addition of power, the pitch attitude began to increase, and the indicated airspeed began to decrease. Recorded data showed that…the airplane pitch attitude increased from 3° airplane nose up at 10,000 feet to 14° airplane nose up at 12,000 feet and that the airspeed decreased from 170 to 103 knots, the speed at which the airplane stalled.

According to the de Havilland DHC-8-103 stall speed chart, the stall speed for the incident airplane in the clean configuration at its weight at the time would have been 89 knots. At the time that the stall began, the airplane’s airspeed was about 103 knots, 14 knots above the predicted stall speed. The increased stall speed was likely due to ice buildup on the wings as evidenced by the increased drag as the airplane climbed from 10,000 feet.

As noted previously, in addition to airspeed indicators, orange speed control indicators providing fast/slow indications were installed in the captain’s and first officer’s ADIs on the instrument panel directly in front of both pilots. The speed control indicators depicted airspeed relative to 1.3 Vstall and would have moved into the “slow” region of the indicator as the airspeed dropped below about 116 knots.

Given that the pitch attitude is a primary control indication and airspeed is a primary performance indication, both pilots (PF and PM) should have been cross checking (that is, continuously and logically observing the instruments for attitude and performance information) both indications frequently.

The captain erroneously believed the airspeed was 150 to 160 knots, and the first officer believed it was c150 knots.  Both pilots reported that they were not aware of the changes in pitch or airspeed, checking neither the airspeed indicator or the fast-slow indication on the ADI.

The first officer stated that normally the PF would specify the climb speed, but he did not recall if the captain did so and he could not remember what the airspeed was in the climb. He said he was busy taking care of paperwork and charts, preparing to communicate with the destination station, looking outside, focusing on the icing conditions, making sure the de-ice boots were inflating, and seeing whether the airplane was shedding ice or not.

As the aircraft began to level off at 12,000 feet it began to shudder.  The flight crew attributed this…

…to an unbalanced condition of the propellers due to uneven ice shedding [which] they had experienced…on their previous flight… FDR data indicate that the airplane was experiencing an aerodynamic prestall buffet; however, neither pilot recognized the buffet as an indication that the airplane was about to stall.

The FDR data showed the control column moving aft from 3° to 8.5° beginning at the time of the loss of lift consistent with autopilot control. This was followed by autopilot disconnection and continued rapid aft movement of the control column to 33° within the next 3 seconds.

…the captain stated that he did not think the stick shaker had activated and that, at the time, he did not realize they were experiencing an aerodynamic stall.

Aerodynamic stall recovery requires the pilot to reduce the airplane’s AOA by pushing the nose down so that proper air flow across the wing and control surfaces can be restored. Therefore, the captain’s aft movement of the control column was an inappropriate response to the stall and impeded its recovery.

At the time, the previous US airliner accident had been the loss of Colgan Air Dash 8 Q400 N200WQ and 50 lives in Buffalo, NY on 12 February 2009 after a stall on approach in icing, when the Captain had also pulled back on the control common.

The FDR also showed that the airplane began a left roll 5 seconds after the initial loss of lift and that the roll coincided with the autopilot disconnection. Following the left roll, pitch decreased from 20° nose up to 37° nose down. The captain stated that he attempted to control the airplane by rolling it to wings level and pulling nose up, but he was unable to regain control. FDR data indicated that the captain held the control column aft to more than 33° for 16 seconds during the descent and that he did not attempt to push the nose over for another 7 seconds after releasing back pressure.

N886EA dash 8 era alaska stall fdr1

N886EA dash 8 era alaska stall fdr2

The captain stated that, during the descent, he made a combination of control and power inputs, pushing the yoke and power forward and back…confirmed by FDR data. Following the initial roll, engine torque on both engines decreased to about 30 percent, and subsequently increased to over 100 percent twice, exceeding the torque limitations on the engines. The captain stated he did not recall seeing any speed during the event as he “never once” looked at the airspeed indicator. As the airspeed increased above 160 knots during the descent, pitch began to increase, and the airplane leveled off at an altitude of about 7,072 feet.

The pilots could not recall if the shaker began to operate at some point during the descent, but, once the captain increased engine power, noise associated with a power increase could have masked the shaker’s sound. However, the flight crewmembers of another Era Aviation airplane listening on the ATC radio frequency during the event stated that they heard background sounds during radio transmissions that sounded like a stick shaker.

NTSB concluded that…

…the captain’s response to the aerodynamic stall delayed the recovery of the airplane…and contributed to the flight’s significant altitude loss.  The…first officer was surprised by the airplane’s loss of control and did not provide any useful assistance to the captain during the recovery.

An Earlier Stall Event in Canada – A Comparison

NTSB note that the Transportation Safety Board of Canada (TSB) had published a safety investigation report into the stall and loss of control of Provincial Airlines Dash 8-100 C-GZKH on 27 May 2005:

Through about 8000 feet, the airspeed started a gradual decrease from 170 KIAS over a period of five minutes. During this time, the vertical speed continued at a constant 1190 fpm up. The gradual decrease in airspeed was detected when the first officer looked up from his paperwork, noted the decreased airspeed, and advised the captain.

The captain then rotated the pitch control wheel on the flight guidance controller toward nose down to increase the airspeed. While attempting the adjustment, the captain saw the aircraft’s stick shaker activate, causing the autopilot to disengage. This occurred at 14 800 feet above sea level, at 104 KIAS. The captain then began to manually fly the aircraft.

Within a second of autopilot disengagement, the aircraft began to roll right and pitch down. Immediately after the aircraft began to roll, it was noticed that there was ice on the left engine inlet. The roll angle increased to 64º, the pitch angle went from 15º nose up to 5º nose up, and the aircraft vertical acceleration dropped to approximately 0.5 g. The aircraft pitch then increased to 30º nose up briefly before decreasing to 40º nose down.

These conditions are indications that the aircraft wing had fully stalled. However, the captain interpreted the indications as severe turbulence. The FDR data show that the aircraft underwent three distinct stalls during the loss-of-control event, with the third stall being the most severe. The data show that the control column position cycled rapidly back and forth as the stall developed, but was moved generally aft, remaining aft during all three stalls. There was significant aileron and rudder pedal movement during the event, but these controls were ineffective in regaining control and were in response to the aircraft’s movement, rather than the cause of it. The data indicated that aircraft control was regained when the control column was moved forward.

This Alaskan Operator, Safety, Training and Procedures

Era Aviation was first certificated in 1979, began scheduled passenger service in 1983 and held a Part 121 certificate since 1991. Era Aviation was sold in 2009 and the new owners, HoTH Inc, merged it with Frontier Flying Service, Hageland Aviation, and Arctic Circle Air Service in 2010 to form Era Alaska.  The company had 73 pilots, 6 Beech 1900s and 6 Dash 8-100s.

The NTSB make a point of highlight that in interview:

A former company check airman stated that a “bush” mentality existed at the company. He stated that pilots were expected to assume greater risk and that experienced pilots were being pushed into adverse situations. For example, pilots were asked to fly during volcano activity and “just skirt around it.” He stated that he also had an experience where he was called to take a flight that another pilot refused, but the company did not tell him that it had been refused. On another occasion, one of the pilots wound up in an emergency because he had not received appropriate weather-related information. He thought the company was being intentionally “right on the edge of legality” and operating in a “wild west” manner. He stated that the company was undoing the progress it had made in safety as a Part 121 carrier.

It should be noted that other current employees at all levels were far more positive in their interview statements.  The head of the local FAA Flight Standards certificate management office described the company as:

…able but are a very slim organization with each responsible party wearing too many hats…[and]…they have many policies but few procedures. The manuals need to be designed to support the operation. Workload has tripled but they haven’t been cognizant of this.  She felt [the operator's] attitude was archaic, and described it as a 20 year old attitude. As an example…offered that when the FAA brings up something for correction ERA’s first reaction is denial and must go through all of the stages of adjustment until they reach acceptance.

Era was a participant in an Aviation Safety Action Program (ASAP), the FAA’s voluntary reporting system, described as follows:

Its focus is to encourage voluntary reporting of safety issues and events that come to the attention of employees of certain certificate holders.  To encourage an employee to voluntarily report safety issues even though they may involve an alleged violation of Title 14 of the Code of Federal Regulations (14 CFR), enforcement-related incentives have been designed into the program.

Revealingly:

The Era Director of Safety (DOS) stated in an interview that…a few years ago a pilot filed an ASAP report and later lost his certificate to FAA action. As a result there was “bad blood” at Era about ASAP. Pilots were reluctant to file reports for fear of retaliation [and] the FAA was perceived by pilots to be “a bully.”

In another interview it was explained that it was actually a mechanic who filed an ASAP report after leaving a cowling unlatched but the FAA suspended a pilot who flew in while unlatched for 90 days.  During NTSB interviews, it was also suggested that an FAA inspector had banned crews from using the company Quick Reference Handbook (QRH) and that pilots had been threatened with a violation if one was found in their flight bags.

In interviews, it was explained that at least 4 IOGP member oil companies chartered Era aircraft. They “all had contract auditors”, and “the company had about one oil company audit per month”. Their customers required an SMS (“a matter of policy” in IOGP Aircraft Management Guidelines Report 390, issued in 2008 but not required then by FAA regulation) yet the operator was still only at a very early stage of developing one (FAA Level 1: Planning and Organisaing).  A few additional oil company requirements were given as examples.  One was extra checks on first officers and the other was “foam in mechanic’s toolboxes” (presumably to outline the tools for tool control purposes).  The company said they were “overwhelmed with audits”.

The NTSB make no further comment on these possible cultural, oversight and customer matters.

In relation to training and procedures:

The Era Aviation Flight Operations Training Program (FOTP) and the de Havilland DHC-8 AFM provide guidance regarding climb and cruise performance, the use of vertical speed (VS) mode, approach to stalls, and flight into icing conditions. The pertinent sections of each are outlined below:

  • According to Era’s FOTP, Paragraph 0263, “Climb Profile,” to set climb power the PM initially sets the engine condition levers to 1,050 rpm and torque to 90 percent. The FOTP provided three climb speed alternatives, 130 kts, 160 kts, or 195 kts, but did not state a minimum climb speed. The PF assumes the responsibility for power adjustments after autopilot engagement.
  • FOTP Paragraph 270, “Climb and Cruise Power,” also provided guidance on the setting of climb power, including charts to be used for setting torque with propeller speeds of 900 and 1,050 rpm. According to Era Aviation’s chief pilot, its climb and cruise power charts were derived from the de Havilland Operating Data Manual.

The Era Aviation FOTP Section 210, “Automation Policy,” dated August 1, 2011, stated that the VS mode shall not be used for sustained climb if the autopilot is engaged since the airspeed is not protected and a stall may occur. The FTOP added that the VS mode may be used to establish the initial climb pitch attitude.

Era Aviation’s stall recognition and recovery procedures were contained in its FOTP, Chapter 9, “Flight Training Procedures, Maneuvers, and Functions,” Paragraph 907, “Approach to Stalls.” The FTOP states, in part, the following [emphasis added]:

  • Pilot performance is judged on ability to RECOGNIZE the approach to stall, prompt action in initiating a smooth recovery, without excessive loss of altitude while holding the assigned heading…Stall recovery is prompt following relaxation of back pressure or application of forward pressure on the control column. Altitude loss can be eliminated by the prompt application of power. Excessive forward movement of the column should be avoided.

Era Aviation’s clean configuration stall recovery procedure was as follows (emphasis added):

  1. Start recovery at earliest warning (stick shaker).
  2. Advance power levers and call “Max Power.”
  3. Reduce back pressure to stop shaker and minimize altitude loss
  4. Accelerate to and climb at VSEC [single engine climb speed] back to original altitude.
  5. Call “climb power” and accelerate to 150 knots.
  6. Call “40 Torque” approaching 150 knots.

Bombardier Dash 8 Flight Manual

On March 4, 2011, Bombardier issued revision 192 to the DHC8-103 AFM. The revision added Section 3.18, “High Angle of Attack Recovery Procedures.”

In contrast to step 3 above:

Under the heading, “Recovery from Stall Warning and Stall (Stick Shaker, Unusual Airframe Buffet, Uncommanded Wing Drop),” the first step was “Autopilot – disengage, and pitch attitude – reduce.” A note was added that stated, “Relax any control column force and/or move the control column forward to achieve a reduction in pitch attitude. This action can result in a loss of altitude.

These revisions were not incorporated into Era Aviation’s FTOP. According to the Era chief pilot, the stall recovery procedures contained in its FTOP were a continuation of a long-standing procedure and he believed that they were consistent with section 3.18 of the AFM even though they did not reflect the idea that altitude loss was acceptable.

Section 4.7.2.2, “Climb, Cruise, and Descent in Icing Conditions,” of the DHC8-103 AFM contained a caution, which applied to flight in all icing conditions, not just severe icing, stating, “An accumulation of ice on the airplane may change the stall characteristics, stall speed, or warning margin provided by the stall warning system.” Era Aviation’s FOTP guidance only pertained to severe icing conditions and did not incorporate this information.

The Flight Crew

The captain, age 41, held an airline transport pilot (ATP) certificate, issued April 30, 2012, with type ratings in Beechcraft BE-1900 (with the limitation that a second-in-command [SIC] was required) and DHC-8 airplanes. The captain was hired by Era Aviation on November 27, 2000. According to the Era Aviation chief pilot, the captain was a DHC-6 Twin Otter first officer from November 2000 to June 2005, a DHC-8 first officer from June 2005 to November 2007, and a BE-1900 captain from November 2007 to May 2012. The captain stated in an interview that he upgraded to captain on the DHC-8 in April 2012. …the captain had accumulated 8,000 total flight hours, including 4,000 hours as pilot-in-command (PIC), 258 hours of which were as PIC in DHC-8 airplanes.

The first officer, age 44, held a commercial pilot certificate, reissued September 22, 2008, with a type rating in BE-1900 airplanes with SIC privileges only. He received his DHC-8 airplane type rating with SIC privileges only on November 19, 2010. …the first officer had accumulated about 6,000 total flight hours, including about 2,360 hours as SIC in DHC-8 airplanes. From December 2004 to September 2007, the first officer flew Cessna 207 airplanes for Grant Aviation in western Alaska. On September 24, 2007, the first officer was hired by Frontier Flying Service. He flew as a BE-1900 first officer for about 11 months and then transitioned to the Piper PA-31 Navajo. The first officer was involved in an accident on August 4, 2008 in a PA-31 airplane in Aniak, Alaska (see NTSB accident ANC08LA097 [N40YR]).

Note this involved a “partial loss of engine power during takeoff due to a failure of the left engine’s turbocharger as a result of the failure of a turbine shaft bearing. Contributing to the accident was unsuitable terrain for a forced landing”.  NTSB concluded that both flight crew…

…were certified in accordance with federal regulations and were current and qualified in the incident airplane in accordance with Era Aviation’s training requirements. Additionally, company records showed that both pilots had completed Era Aviation’s training with no issues or discrepancies.

However:

Despite a record of success, the captain showed occasional lapses of attention and judgment. A former check airman said he performed well in the simulator but was not always attentive. The check airman said the captain once made multiple attempts to land the DHC-8 at a field where crosswinds were 40 knots, which is greater than allowable limits (the AFM maximum allowable crosswind component for the DHC8-103 is 36 knots). A first officer stated that the captain was sometimes talkative in flight and they had to stop talking to give priority to the mission. Some first officers had expressed concerns that he sometimes lacked focus and attention and was not always “in the moment.” Other pilots had commented to the assistant chief pilot that the incident captain was not unsafe but that he could get behind the airplane.

Era Aviation vice president of operations stated that the captain had …showed occasional lapses of attention and judgment, which company management and pilots were aware of but took no actions to address.

Meanwhile:

A captain who had flown with the first officer indicated that he could not do a lot of things at once and “needed time to get his ducks in a row.” He stated the first officer’s situational awareness was weaker than other pilots. Another captain who had flown with the first officer said he could get flustered and become easily overwhelmed with routine tasks such as weight and balance.

NTSB Probable Cause

In-flight loss of control due to the flight crew’s inattention to airspeed, pitch attitude, and engine power during the climb leading to an aerodynamic stall.

Contributing to the incident was the flight crew’s failure to recognize and properly recover from an aerodynamic stall in a timely manner.

Note tooe similarities with the 2009 Colgan Air probable cause:

The captain’s inappropriate response to the activation of the stick shaker, which led to an aerodynamic stall from which the airplane did not recover. Contributing to the accident were (1) the flight crew’s failure to monitor airspeed in relation to the rising position of the low-speed cue, (2) the flight crew’s failure to adhere to sterile cockpit procedures, (3) the captain’s failure to effectively manage the flight, and (4) Colgan Air’s inadequate procedures for airspeed selection and management during approaches in icing conditions

Era Aviation’s Post Incident Safety Actions

On 10 November 2012, Era issued Ops Bulletin 1-12, “9-5 Incident Post Flight Directive/Procedural Changes.” The key provisions were:

  • Minimum en route climb airspeed shall be 130 knots.
  • Standard climb power will normally be used.
  • DHC-8 climb power will be taken from the chart “type II – 1050 RPM.”
  • Use of VS mode in climb will be prohibited.
  • Max continuous power will be used to exit icing conditions greater than light icing.
  • PF will normally maintain contact with the power levers.

Era also stated that it “would review the pilot hiring and upgrade process” and “institute full stall entry and recovery training”.

NTSB Safety Recommendations

On 1 May 2014, in response to this incident and five other accidents by operators owned by HoTH Inc NTSB issued two Safety Recommendations to the FAA.

Conduct a comprehensive audit of the regulatory compliance and operational safety programs in place at operators owned by HoTH, Inc., to include an assessment of their flight operations, training, maintenance and inspection, and safety management programs, and ensure that permanent corrective action is implemented for all adverse findings. This audit should be conducted by a team of inspectors from outside Alaska. (A-14-22) (Urgent)

Conduct a comprehensive audit of the Federal Aviation Administration (FAA) oversight of 14 Code of Federal Regulations Part 135 and Part 121 certificates held by operators owned by HoTH, Inc., and ensure that permanent corrective action is implemented for all adverse findings. This audit should be conducted by a team of inspectors from outside Alaska and should include a review of inspector qualifications, turnover, working relationships between the FAA and operators owned by HoTH, Inc., and workload to determine whether staffing is sufficient. (A-14-23)

Both recommendations have since been closed-acceptable action.

Safety Resources

Past Aerossurance articles include:

…and our review of The Field Guide to Understanding Human Error by Sidney Dekker presented to the Royal Aeronautical Society (RAeS): The Field Guide to Understanding Human Error – A Review


Aerossurance was to have run workshops at the EHA European Rotors VTOL Show and Safety Conference in Cologne in November 2020 on a) Safety Culture and Leadership and b) Contracting Aviation Services: An Introduction to the Basics.  Sadly due to COVID-19 the show has been postponed.

european rotors 2020 postponed

 


Aerossurance has extensive air safety, operations, SAR, airworthiness, human factors, aviation regulation and safety analysis experience.  For practical aviation advice you can trust, contact us at: enquiries@aerossurance.com

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