On 2 October 2015, at approximately 0016 hours, local time (L), a C-130J crashed after takeoff from Runway 31, Jalalabad Airfield (JAF). On 1 October 2015, at approximately 2313L, the MA landed at JAF following the first scheduled leg of a contingency airlift mission. While on the ground, the MP placed a hard-shell night vision goggle (NVG) case forward of the yoke during Engine Running Onload/Offload (ERO) operations to maintain the MA elevator in an up position to accommodate loading operations of tall cargo. In the 50 minutes that followed prior to take-off at 0015L, neither the mishap pilot (MP) nor the mishap copilot (MCP), removed the case. During the takeoff roll, with the MCP at the controls, the mishap aircraft (MA) rotated early and lifted off the ground approximately three knots below the anticipated takeoff speed. The MA’s pitch angle continued to increase due to the hard-shell NVG case blocking the flight controls, thus preventing the MCP from pushing the yoke forward to decrease the pitch angle. The MCP misidentified the ensuing flight control problem as a trim malfunction resulting in improper recovery techniques being applied by both mishap pilots. The rapid increase in pitch angle resulted in a stall that the mishap pilots were unable to recover. The MA impacted approximately 28 seconds after liftoff, right off the runway, within the confines of JAF. Final report released in April 2016.
Prospective memory—remembering to perform an action that cannot be executed when the intention is formed—is distinguished by three features: (1) an intention to perform an action at some later time when circumstances permit, (2) a delay between forming and executing the intention, typically filled with activities not directly related to the deferred action, and (3) the absence of an explicit prompt indicating that it is time to retrieve the intention from memory—the individual must “remember to remember.”
Typically, if queried after forgetting to perform an action, individuals can recall what they intended to do. The critical issue in prospective memory is not how we retain the content of our intentions but how we remember to perform those intentions at the appropriate moment, and why we sometimes fail to remember.
United States Air Force Accident Investigation Board Report
C-130J, Jalalabad Airfield, Afghanistan
C-130J, T/N 08-3174, 2 October 2015
On 2 October 2015, the mishap aircraft (MA), a C-130J, T/N 08-3174, departed JAF on the second scheduled leg of a contingency airlift mission at 0015 hours local time (L) (Tabs K-4, N-17, CC-55, and CC-57). The mishap crew (MC) from the 774th Expeditionary Airlift Squadron (EAS) at Bagram Airfield (BAF), Afghanistan, consisted of the mishap pilot (MP), the mishap copilot (MCP), and two mishap loadmasters (MLs) (hereinafter Mishap Loadmaster 1(ML1) and Mishap Loadmaster 2 (ML2)). Additionally, two Fly-Away Security Team (FAST) members, five contractors traveling as passengers, and 39,386 pounds of cargo were aboard the aircraft. The MCP performed an adjusted maximum effort (AMAX) takeoff reaching a maximum nose-up pitch attitude of 42 degrees while climbing to approximately 700 feet above ground level (AGL). Approximately 12 seconds after takeoff, the MA entered a stall due to the high pitch angle. The MP and MCP were unable to recover from the stall. At approximately 0016L, the MA impacted the ground 14 degrees nose-low in 28 degrees of right bank at an airspeed of 111.5 knots and was destroyed. All eleven personnel onboard died upon impact. Additionally, three Afghan Special Reaction Force (ASRF) members on the ground were killed. Total Department of Defense (DoD) damage cost was $58,363,044, which includes the loss of the MA worth $51,606,131 and cargo worth $6,756,913. Additionally, a JAF guard tower and perimeter wall were damaged.
SEQUENCE OF EVENTS
The planned mission consisted of two round-trip transport flights from BAF (airport designator OAIX) to JAF (airport designator OAJL), followed by a flight to Kabul, a flight to Kandahar Airfield, and a final return to BAF for mission termination. The mishap sortie (MS) was the second scheduled leg of this mission, taking off from JAF for the return to BAF. The Air Mobility Division Chief at the 609 AOC
(1) Crew Composition
The MP was the aircraft commander. He was in the left seat during the MS and was the pilot monitoring the controls during the takeoff roll. The MCP was the pilot flying during the takeoff roll and was in the right seat. ML1 and ML2 were posted in the cargo compartment.
(2) Airspace Considerations
The MS was flown in airspace controlled by US contractors from the Jalalabad Air Traffic Control Tower (hereinafter “Tower”). The MC maintained radio contact with the Tower throughout the flight. The Tower was able to keep the MA in view during the takeoff roll through liftoff before losing sight of the MA at the departure end of the runway due to the night flying environment. Other aircraft were not in Tower’s airspace during the MS.
Summary of Accident
(1) Bird-Strike Sortie
The first sortie flown by the MC on 1 October 2015 was a planned flight from BAF to JAF. The MA took off as scheduled at 2136L. After takeoff, the MA experienced a bird strike and returned to BAF to allow maintenance personnel to inspect the MA before continuing the mission. The MC landed at 2155L, taxied to park, and returned the MA to maintenance for inspection. At this time, the MP and MCP returned to the operations building. They informed the ADO of the bird strike and their plans to continue the mission. The MP and MCP did not seem concerned by the event; once cleared by maintenance, they returned to the MA to continue the mission as planned.
(2) Flight to Jalalabad Airfield (JAF)
The MC took off for JAF at approximately 2253L. The sortie was uneventful and the MA landed safely at JAF at approximately 2313L. The MP and MCP noted fireworks during the approach into JAF, but did not consider it enemy action and did not execute evasive maneuvers. The MCP relayed this information back to unit leadership.
(3) Loading & Ground Operations
The MP taxied to Alpha Ramp to begin Engine Running Onload/Offload (ERO) procedures at 2316L. The AIB determined the local times referenced throughout the remainder of the sequence of events based on matching a known cockpit voice recorder (CVR) time stamp with a digital flight data recorder (DFDR) time stamp. The AIB then extrapolated the DFDR time stamps and applied them to the CVR, thus providing a consistent time reference throughout the report. The MC followed the ERO checklist in accordance with the planned mission. The FAST members took their position outside the MA prior to the cargo offload. During the cargo offload sequence, ML1 requested that the MP raise the elevator on the MA to provide more clearance for offloading the high-profile (tall) cargo.
Raising the elevator lifts the control surface above horizontal and is accomplished by pulling the yoke aft (toward the pilot). This request was not considered an unusual request by the MP who did comply at 23:19:49L (DFDR time 4710). For the next six minutes, there were changes in the elevator deflection, indicating that the MP was holding the yoke back to maintain between positive 6 and positive 13 degrees of elevator deflection. At 23:26:06L (DFDR time 5087) the elevator position increased to positive 20 degrees deflection momentarily before settling to a position between six to eight degrees positive deflection. This occurred immediately before the MP told the MCP, “My NVG case is holding…the elevator” as demonstrated in Figures 4-1 and 4-2.
The natural resting state of the elevator during ground loading operations is approximately negative 15 degrees deflection, as demonstrated in Figure 4-3. On the MA, the elevator position remained between six to eight degrees positive deflection while loading operations continued, as demonstrated in Figure 4-4. This positive elevator deflection was confirmed by video evidence of the MA loading operations, depicted in Figures 4-5 and 4- 6. Approximately ten minutes after the hard-shell NVG case was placed forward of the yoke, the MCP got out of the right seat to assist with loading operations in the back of the MA .
The MLs were tasked with on loading five pallets utilizing ERO procedures. The on load also included five passengers not included in the original load plan, prompting a decision by the MLs to move the forward-most pallet aft to pallet position three rather than pallet position two. This decision was in accordance with (IAW) AFI 11-2C-130J Volume 3, C-130J Operations Procedures, 8 December 2009. This load change shifted the center of gravity (CG) to 28.6% of Mean Aerodynamic Chord (MAC) for takeoff. The total load weight was 40,300 pounds (including the passengers) and the calculated aircraft gross weight for takeoff was 153,200 pounds. The cargo weight and CG computed based on the new load plan was within flight limits and met all requirements for safe flight.
During cargo loading operations, the MP was in the left pilot seat determining if the MA’s performance would be sufficient to takeoff from JAF. The MP initially expected the MC would need to perform an AMAX (Adjusted Maximum Effort) takeoff instead of a normal takeoff, which would allow the MA to takeoff in a shorter runway distance and at a lower takeoff speed.
The MP then verified that the load weight was 40,300 pounds. After running the Takeoff and Landing Data (TOLD) calculations, the MP acknowledged that they had 750 feet of runway available beyond what was required for takeoff. AIB calculations show this matches the distance required to perform a normal takeoff. The MCP returned to the right seat at approximately 0002L and the MP confirmed that they would perform an AMAX takeoff, with an expected liftoff speed of 111 knots. The AIB calculated the normal takeoff speed for the MA would have been 122 knots.
Throughout the remainder of the ground operations, the mishap pilots did not discuss the hard shell NVG case holding the elevator in a raised position; video and DFDR data confirmed that the elevator remained in its raised position until the takeoff roll.
The blocking of flight controls during loading operations was a nonstandard procedure and there was no regulatory guidance to accompany the proper placement and removal of an object blocking the controls. The ERO checklist did not include a step requiring the pilots to check the flight controls prior to departure; therefore, it was incumbent on the MP and the MCP to remember to remove the hard-shell NVG. To check the flight control, the MP or MCP would move the yoke forward and aft to confirm full range of motion. When accomplished, all flight control checks occur solely within the flight deck; no external check would have been accomplished that may have alerted the MP or MCP to the raised elevator position. The AIB could not determine whether a flight control check would have alerted the MP or MCP to the hard-shell NVG case forward of the yoke.
(4) Mishap Sortie (MS)
After the completion of the ERO the MC taxied to the active runway and back-taxied for takeoff on Runway 31. The MP and MCP were wearing NVGs for the takeoff. Tower called the winds at three knots from 220 degrees. There was no elevator movement up to this point, indicating that the MP and MCP had not removed the hardshell NVG case from forward of the MP’s control yoke.
The MCP conducted the takeoff from the right seat and began the takeoff roll at 00:15:24L. Normally during a takeoff roll, the pilot keeps the elevator deflected down until the aircraft reaches rotation speed, at which point the pilot pulls the yoke aft, which raises the elevator, and the aircraft becomes airborne. During the MA’s takeoff roll, the elevator deflection decreased from positive six to eight degrees to positive three to five degrees. This slight change is consistent with aerodynamic forces across the elevator surface. The MA passed the briefed acceleration time check and the MP called rotate at 00:15:50L. The MA became airborne at 00:15:50L at an indicated airspeed of 107.5 knots.
After the MP called “Rotate” at 00:15:50L (Figure 4-11), the MCP responded that the MA was “going off on its own” at 00:15:54L. The MCP became aware of a problem at 00:15:56L when he stated, “Ahh,” and verbalized a trim failure two seconds later (00:15:58L) as the MA reached its top airspeed of 117 knots. The MCP applied full nose-down trim in an attempt to help move the yoke forward at 00:15:57L. The trim reached full negative deflection in three seconds, indicating that the trim system was operating normally. The MA continued to pitch up as the mishap pilots attempted to remedy the perceived trim malfunction (Tabs L-4 and CC-32 to CC-35). Three seconds after the MCP verbalized a trim malfunction, the first stall warning occurred at 00:16:01L (Figure 4-11). The MA was at greater than 20 degrees nose-up pitch, wings level, and an airspeed of 115 knots .
At approximately 00:16:02L, when the MA was at 25 degrees of positive pitch, the MP, already in control of the MA, applied right aileron, and began rolling the MA to the right. This input is consistent with the MP attempting to maintain controlled flight. At 00:16:02L, the MA entered a stall and, except for a brief period just prior to impact, remained stalled throughout the remainder of the MS. At 00:16:03L, the MA issued a second stall warning as the MA’s pitch continued to increase through 35 degrees nose-up (Figure 4-11).
Pitch Angles of MA w/ Time Stamps The stick pusher, a device that applies approximately 49 to 71 pounds of forward column force to the yoke to reduce the angle of attack (AOA), activated just prior to the second stall warning. During AIB simulations with the hard-shell NVG case behind the yoke, the stick pusher activated but was ineffective because of the blocked controls. At 00:16:05L, the MP confirmed he had control of the MA and directed the MCP to select emergency trim, an alternate to the normal trim system. At 00:16:06L, the MCP confirmed he had selected emergency trim; however, the DFDR shows the trim system functioned properly in the normal position and the MCP switching to emergency trim had no additional effect. The pitch and roll continued to increase until the MA reached a maximum positive pitch of 42 degrees at 00:16:07L (Figure 4-12). The MA issued a third stall warning at 00:16:07L. The roll continued to increase through the stall and the MA’s nose dropped. The MP input left aileron to correct the roll but due to the stalled condition, the right roll continued to increase. The MA reached a maximum right bank of 75 degrees at 00:16:12L.
At approximately 00:16:13L, the MA began to roll to the left. The MA’s nose continued to drop, eventually reaching negative 28 degrees pitch at 00:16:15L (Figure 4-12). At 00:16:15L, the MP stated, “We’re going down,” a statement he repeated three consecutive times.
At 00:16:15L, the nose-down pitch angle was arrested as the MA nose started to rise.
With a descent rate in excess of 8,000 feet per minute, the MA impacted the terrain, a perimeter wall to the right of the runway, and a guard tower at a force from 40g to more than 97g . The MA impacted at 14 degrees nose-down, 28 degrees of right bank, airspeed of 111.5 knots, and approximately 50% flaps at 00:16:18L, 28 seconds after becoming airborne (Figure 4-12). The MA exploded upon impact and was destroyed.
HUMAN FACTORS ANALYSIS
The DoD Human Factors Analysis and Classification System (HFACS) version 7.0 lists potential human factors that can play a role in mishaps. It is designed for use by an investigation board in order to accurately record all aspects of human performance associated with an individual and the mishap event. DoD HFACS helps investigators perform a more accurate investigation, classify particular actions (or inactions) that sustained the mishap sequence, and contribute to a safety database as a repository for detecting mishap trends and preventing future mishaps. The DoD HFACS classification taxonomy divides the failures into active failures and latent failures. Active failures, or “Acts,” are the actions or inactions of individuals that most immediately lead to a mishap. Latent failures may remain undetected for some period of time prior to their manifestation as an influence on an individual’s actions during a mishap). Latent failures and conditions are divided into Preconditions, Supervision, and Organizational Influences. The discussion below lists the human factors directly involved in this mishap. Each of the following factors falls under the categories of Acts or Preconditions:
1. Inadequate Real-Time Risk Assessment
Inadequate Real-Time Assessment is a factor when an individual fails to adequately evaluate the risks associated with a particular course of action, and this faulty evaluation leads to inappropriate decision-making and subsequent unsafe situations.
The MP placed a hard-shell NVG case forward of the left seat control yoke during the ERO. The ERO continued for approximately 50 minutes after the elevator was blocked. The blocking of flight controls during loading operations was a nonstandard procedure and there was no regulatory guidance to accompany the proper placement and removal of an object blocking the controls. The ERO checklist did not include a step requiring the pilots to check the flight controls prior to departure and therefore, it was incumbent on the MP and the MCP to remember to remove the hard-shell NVG case. The MP did not adequately evaluate the risk associated with blocking the elevator controls with the hard-shell NVG case.
Distraction is a factor when the individual has an interruption of attention and/or inappropriate redirection of attention by an environmental cue or mental process. The MC landed at JAF at 2313L and began the ERO at 2316L. During the cargo offload, ML1 requested that the MP raise the elevator to provide more clearance for the high-profile cargo during ERO operations. For the next six minutes, there were changes in the elevator deflection between the range of positive 6 and positive 13 degrees of deflection. At 23:26:06L (DFDR time 5087) the elevator position increased to positive 20 degrees deflection momentarily before settling to a position between six to eight degrees positive deflection. This occurred immediately before the MP told the MCP that the “NVG case is holding…the elevator”. The elevator position remained steady between six to eight degrees positive deflection until the takeoff roll.
During the 50 minutes after the MP placed the case forward of the yoke, the MP’s and MCP’s attention was redirected towards discussing loading operations, aircraft gross weight, climb-out procedures, and TOLD. Neither the MP nor the MCP referenced the case again.
3. Wrong Choice of Action During an Operation
The wrong choice of action during an operation is a factor when the individual, through faulty logic or erroneous expectations, selects the wrong course of action.
During the takeoff sequence, the MA lifted off the ground greater than three knots below the calculated AMAX takeoff speed. The MCP, who was performing the takeoff, recognized a control problem identified on the CVR at 00:15:56L. Two seconds later, the MCP incorrectly identified the flight control malfunction by stating “Trim failure”. The first stall warning indication occurred three seconds after the verbal misidentification of a trim malfunction. Due to the rapid progression of the nose-up pitch attitude, the mishap pilots had eleven seconds from MA liftoff until the first stall warning indication to identify and correct the malfunction.
4. Environmental Conditions Affecting Vision
Environmental Conditions Affecting Vision is a factor that includes obscured windows; weather, fog, haze, darkness; smoke, etc.; brownout/whiteout (dust, snow, water, ash or other particulates); or when exposure to windblast affects the individual’s ability to perform required duties.
Three inter-related environmental conditions affecting vision were factors in this mishap: Night time operations, use of NVGs, and reliance on the HUD in conjunction with the ACAWS notifications.
The MA landed at JAF at 2313L. The weather was VMC with 9,000 meters visibility. The predicted lunar illumination at takeoff was approximately 81 percent. Due to the operations occurring at night, the MC wore NVGs. It was standard operating procedure for aircrews operating on NVGs to dim the cockpit lights and increase the brightness of the HUD.
NVGs permit aircrews to operate more effectively in low-illumination environments. The field of view (FOV) the NVGs provide is less than the eye’s natural FOV, particularly in peripheral vision. Therefore, a person must constantly process two input components to his visual system. The two components are: focal vision, which is primarily responsible for object recognition, and ambient vision, which is responsible for spatial orientation. This reliance on focal vision increases the aviator’s workload and ultimately decreases the recognition of peripheral cues.
The information provided by the HUD, combined with the ACAWS, allowed aircrews to maintain their visual scan external to the aircraft with only occasional crosschecks of the HDD to monitor aircraft systems. Due to the HDD design, internal crosschecks of aircraft systems were normally done without the aid of NVGs. Prior to the takeoff roll, the MCP and MP checked the horsepower setting. After this, all information required to perform the takeoff was available in the HUD.
During the AIB’s simulations at Little Rock Air Force Base, the AIB Pilot Member (AIB/PM) dimmed flight deck lighting to replicate nighttime operations. The hard-shell NVG case placed forward of the yoke became inconspicuous to all three AIB pilots during the course of multiple takeoff sequences.
5. Inaccurate Expectation
Inaccurate Expectation is a factor when the individual expects to perceive a certain reality and those expectations are strong enough to create a false perception of the expectation.
The MP initially expected the MC would need to perform an AMAX (Adjusted Maximum Effort) takeoff instead of a normal takeoff. The MP then verified that the load weight was 40,300 pounds. After running the TOLD calculations, the MP acknowledged that they had 750 feet of runway available beyond what was required for takeoff. AIB calculations showed this matched the distance required to perform a normal takeoff. When later asked by the MCP, the MP confirmed that they would perform an AMAX takeoff.
The decision to perform an AMAX takeoff resulted in a planned rotation speed of 111 knots instead of 122 knots associated with a normal takeoff. During the MS, the MA lifted off at 107.5 knots, only a few knots below the planned rotation speed. For a normal takeoff, had the MA lifted off at 107.5 knots instead of 122 knots, it may have provided a more pronounced alert of the problem to the mishap pilots, allowing them to abort the takeoff. The MP’s inaccurate expectation that an AMAX takeoff was required led to an unnecessary AMAX takeoff.
Fixation is a factor when the individual is focusing all conscious attention on a limited number of environmental cues to the exclusion of others .
At liftoff, the MP reported “You’re a little early;” the MCP replied “It’s going off on its own”. Six seconds after liftoff, the MCP became aware of a problem with the MA . He then misidentified the problem as a trim failure and the MP instructed him to “Go emergency”. During the five seconds from when the MCP first realized something was wrong (00:15:56L) to the first ACAWS stall warning (00:16:01L), both MP and MCP focused their attention on a trim failure problem. The mishap pilots neither verbalized a different flight control problem nor attempted to reduce power to control the increasing aircraft pitch.
Excerpted from the United States Air Force, Aircraft Accident Investigation Board Report. C-130J, T/N 08-3174, 774th Expeditionary Airlift Squadron, 455th Air Expeditionary Wing, Bagram Airfield, Afghanistan, released April 2016. http://asndata.aviation-safety.net/reports/2015/20151002-2_C130_08-3174.pdf
Prospective memory demands in cockpit operations emerge in five types of task situations:
1) Episodic tasks. In these situations, pilots must remember to perform at a later time some task that is not habitually performed at that time. For example, an air traffic controller may instruct a crew to report passing through 10,000 feet while the crew is still at 15,000 feet, creating a delay of perhaps five minutes. Another example occurs when circumstances force pilots to perform a habitual task out of its normal sequence. Most laboratory research on prospective memory has focused on these types of episodic tasks.
2) Habitual tasks. Crews perform many tasks and many sub-task steps in the course of a normal flight. On the order of a hundred action steps are required just to prepare a large aircraft for departure. Most of these steps are specified by written procedures, and are normally performed in the same sequence, thus, execution of tasks becomes highly habitual for experienced crews. For example, flaps are normally set to takeoff position after the engines have been started and before taxiing to the runway. Pilots do not have to form an episodic intention to perform each of these action steps, rather the intention to perform each step is implicit in the action schema for the task, stored in procedural memory. Thus, pilots do not have to form an explicit intention in advance each time they must set the flaps.
One might argue whether performing highly habitual tasks fits the definition of prospective memory. Although habitual tasks differ substantially from episodic tasks, we include them as a form of prospective memory because the individual must retrieve the action to be taken when circumstances are appropriate without receiving any explicit prompt to retrieve the memory item. Individuals who forget to perform habitual tasks typically report that they intended to perform the task.
3) Atypical actions substituted for habitual actions. Circumstances sometimes require crews to deviate from a well-established procedural sequence. For example, through long experience departing from a certain airport, a crew would come to know that the Standard Instrument Departure procedure (a written instrument procedure) requires them to turn left to 300 degrees upon reaching 2000 feet. This would become habitual for the crew. If on the rare occasion a controller told them to turn to 330 degrees instead of 300, the crew would have to both form an episodic intention to turn to 330 degrees and an intention to inhibit their habitual response of leveling the wings at 300. Reason (1984) discussed memory errors in such situations as habit capture.
4) Interrupted tasks. Interruptions of procedures occur fairly frequently, especially when crews are at the gate preparing the airplane for departure. Flight attendants, gate agents, mechanics, and jumpseat riders frequently interrupt the pilots as they work to complete preflight procedures. Pilots may try to finish the immediate task they are working on before addressing the person interrupting them, or they may suspend the ongoing task to handle the interruption. In either case, attention is diverted at least momentarily by the intrusion, and pilots must remember to resume where they left off. A common form of error is to move on to the next task in the normal procedural sequence, failing to return to and complete the interrupted task. Pilots generally either recognize that the interrupted task has not been completed or recognize that they are not certain of its status.
5) Interleaving tasks. Pilots must often “multitask,” interleave two or more tasks concurrently, somewhat like a circus performer twirling plates on poles. For example, first officers must sometimes re-program the flight management system while the airplane is taxiing to the runway (perhaps because the original runway or the original departure clearance has changed). But during taxi, the first officer is also responsible for other tasks, including monitoring the course of the taxi (to catch potential errors by the captain), handling radio communications, and—depending on the airline—various other tasks. If the reprogramming can be accomplished with a few keystrokes the first officer may do this all at one time, but if the re-programming takes longer it is necessary to interleave performing some programming steps with performing other cockpit duties, switching attention back and forth. It is easy for pilots to become preoccupied with one attention-demanding task (for instance, if a programming glitch occurs) and forget to interrupt themselves to check the status of other tasks frequently enough (Dismukes, Young, & Sumwalt, 1998). ( Excerpted from : A. Kramer, D. Wiegmann, & A. Kirlik (Eds.) Attention: From Theory to Practice. New York, NY.Oxford University Press (2007))
On the other hand, do you remember “Norms”, one of The Dirty Dozen Factors of Human Error? Norms are those practices than follow unwritten rules or behaviors, which deviate from the required rules, procedures and instructions.
By Laura Duque-Arrubla, a medical doctor with postgraduate studies in Aviation Medicine, Human Factors and Aviation Safety. In the aviation field since 1988, Human Factors instructor since 1994. Follow me on facebook Living Safely with Human Error and twitter@dralaurita. Human Factors information almost every day