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A Matter Of Procedures

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THE INCIDENT INVESTIGATION WE’RE EXPLORING this month comes from the U.K.’s Air Accident Branch (AAB). No lives were lost, and damage to the aircraft was minor, but the accident turned out to be the last straw for the air carrier – Emerald Airways Ltd. Its circumstances demonstrate the importance of adhering to approach SOPs, particularly when a mismatch in crew experience exists.

Investigator-in-charge R. D. G. Carter and his team were called to Guernsey Airport in the Channel Islands on March 8, 2006, after a Hawker Siddeley HS 748 2A ran off the end of Runway 27 after landing long. Once they determined that the airplane had been mechanically sound, the AAB team members focused on the crew and the oversight of air operations by both the company and the U.K.’s Civil Aviation Authority.

In short, the investigators found that the crew did not comply with SOPs for CAT I ILS approaches; that the captain made the go/no-go landing decision late; that the crew did not immediately apply maximum braking or configure the airplane properly for the stop; and that the operator’s training staff lacked knowledge of the SOPs. Contributing to the incident, said the U.K. safety board, was the fact that “close monitoring by the CAA had not revealed the depth of the lack of knowledge of Standard Operating Procedures within the operator’s flight operations department until after this incident.” Before the accident, Emerald had been the subject of close monitoring by the CAA over a sustained period and its Air Operator’s Certificate (AOC) was later suspended.
Here’s the Story

The crew of the Emerald Airways cargo flight reported for duty at Coventry Airport at 0615 hours for a two-leg flight to Jersey and Guernsey. They would be piloting one of the company’s HS 748s. The captain was well experienced with 8,300 hours total and some 4,000 hours in the twin turboprop. He was a type rating examiner (TRE) and an instrument rating examiner (IRE) on the HS 748, and was also employed as a crew resource management instructor (CRMI) by the operator. Emerald Airways had assessed his performance as “exceptional” during his last operator proficiency check (OPC) and line check. By contrast, the copilot had logged a total of just 988 hours, with 150 hours in type. Simulator training was not available for the 748, and this flight would be the first time the copilot had experienced instrument conditions to minimums on a landing approach. It would also be the first time the pilots had flown together.

Departure from Coventry was delayed because of runway construction work, but eventually the flight lifted off at 0930. The HS 748 was carrying extra fuel reserves in case they had to return to Coventry if the poor weather in the Channel Islands got below minimums.

The Jersey leg, on which the copilot was the pilot flying (PF), was uneventful and the crew successfully completed an ILS approach to Runway 27. (The airplane had no autopilot.) On that approach, the pilots saw the runway at a height of about 800 feet above airport level. During the turnaround, the larger part of the cargo was offloaded and the airplane was refueled to 9,020 pounds, enough for the flight to Guernsey and a following leg to Hamburg with a new crew.

Before the aircraft departed from Jersey, the captain, who was the PF for the 15-minute flight to Guernsey, conducted a briefing for the ILS approach to Runway 27 at Guernsey. He told the copilot to monitor the approach and, following the PNF “500 above” challenge and response call, to look out and check for any visible signs of the approach lighting, while the captain continued to focus his attention on the flight instruments.

The captain said that he would advise the copilot of any corrections he was making to the aircraft’s flight path. He also briefed that at the decision altitude (DA) of 540 feet msl, one of the two would call “at minimums” and that the copilot should call “nothing seen” or “I have the lights,” as appropriate. If the copilot called “nothing seen,” the captain would initiate a go-around. (During the investigation, the captain stated that at the DA the aircraft needed to be within a deviation of “one dot” on both the glideslope and localizer indications, otherwise a go-around should be initiated.)

The crew delayed their departure from Jersey because the RVR at Guernsey was less than the minimum 550 meters required for the planned ILS approach to Runway 27. Ultimately, the visibility in Guernsey improved and the aircraft departed with 2,092 pounds of freight.

When the HS 748 was established in cruise at 2,000 feet, the copilot checked the Guernsey ATIS. At 1144, Information Kilo was current and gave the surface wind as 230degrees/21 knots, visibility 350 meters with the Runway 27 RVR 1,500 meters, moderate rain, fog, broken cloud below 100 feet agl, temperature 10ýýC, dew point 9ýýC and a QNH pressure setting of 1,004 millibars. The ATIS transmission also advised that the runway surface was wet throughout its length and that ATC Low Visibility Procedures were in force. While the copilot was obtaining this information the captain was advised by ATC that a DHC-8 had just landed.

With the RVR for Runway 27 greater than the minimum visibility required, the flight was able to continue with the planned ILS approach to Runway 27, but because of the crosswind conditions, the captain had briefed that they would land with 22.5 degrees of flap – one stage less than the full 27.5 degrees of flap available – for greater roll control.

ATC provided radar vectors and the aircraft was established on the localizer at nine nm with 15 degrees of flap selected and the landing gear extended. The flight was instructed to transfer to the ATC tower frequency and, as it intercepted the glideslope, the pilots selected 22.5 degrees of flap. The aircraft was cleared to land and the ATC advised that the surface wind was 230 degrees/18 knots. The Vat of 97 knots (speed crossing the threshold while landing), for a landing weight of 36,800 pounds and flap setting of 22.5 degrees, had been confirmed during the cruise and the captain kept the speed between 100 and 110 knots while they descended on the ILS.

The tower controller continued to give the crew regular updates on the RVR as it dropped to 900 meters, then increased to 1,200 meters before decreasing back to 900 meters. During the approach, the flight was also given updates on the surface wind, which varied in direction between 220 degrees and 250 degrees and between 15 knots and 22 knots. In the early stages of the descent, the captain noticed that he did not have to make much allowance for crosswind. However, toward the end of the approach he advised the copilot that he was having to allow for a drift to the right. The surface wind reported just before the landing was 230degrees/15 knots.

The copilot later told investigators that he saw a lateral deviation from the localizer of about one-half a dot during the approach. He made the “500 above” challenge and response call, reminded the captain that the DA was 540 feet msl and advised him that he was “looking out.” Some 40 seconds after that, the captain advised the copilot that the aircraft was slightly below the glideslope but correcting. Twenty seconds later, the EGPWS activated a glideslope audio warning. There was no verbal challenge from the copilot. After another 40 seconds, the CVR recorded a call of “Minimums,” although its source is not clear. The copilot reminded the captain of the DA, to which the captain responded that he was going to continue descending “for a second” before deciding if he could see the lights. The copilot advised the captain that there was still a bit further to go to their “decision.”

The accompanying figure shows Runway 27 at Guernsey, with indications of the aircraft’s likely positions. On hearing a “Minimums, minimums” audio advisory, the captain asked the copilot if he could see anything. The copilot replied that he could see the lights just to the left, that they were going left and that he could see the touchdown marks. He asked the captain if he was visual and the captain confirmed that he was. The captain later recalled observing that the aircraft’s left wingtip was over the right edge of the runway. He maneuvered the aircraft to the left, during which time, the crew commented later, the aircraft “may have ballooned slightly.” He selected the power levers to flight idle and the aircraft touched down smoothly. It was raining.

After landing, the captain switched on his windscreen wiper and applied the brakes. He had not seen the Precision Approach Path Indicators (PAPIs) – nor had the copilot – but was not surprised, thinking that the aircraft had landed slightly beyond the touchdown zone. However, he then realized that they had landed farther down the runway than intended.

The captain applied maximum braking because the aircraft was not decelerating as quickly as he wanted. He later told investigators that he was under the impression that the copilot had moved the lever to withdraw the flight fine pitch stops (FFPS) immediately after touchdown and the copilot later recalled making an attempt to do this. The copilot recalled that the aircraft initially seemed to slide to the left “as if on ice,” before the captain appeared to make a correction with rudder.

The copilot felt the aircraft slowing down, heard the captain call for the “Locks” and attempted to engage the control locks. The locks would not engage and he tried to center the rudder pedals, which he later described as “the normal solution.” He became aware that the aircraft had stopped slowing down, as if it was “gliding along,” and he was surprised to see the red and white centerline lights, which signified that the aircraft was between 900 and 300 meters from the end of the runway. He could see the end of the runway and considered that the aircraft might be hydroplaning. With the “stop” end lights getting closer, the copilot applied his brakes but that did not appear to have any effect.

Personnel on duty in the tower first observed the aircraft when it was about halfway down Runway 27 at a height of approximately 50 feet. The aircraft then disappeared from view behind cloud. The tower controller realized that the aircraft was not well placed for a landing but paused before calling the aircraft because he “thought that the crew were probably busy.” During that pause the airfield’s Rescue and Fire Fighting Service (RFFS) reported to ATC that they were “rolling,” having seen the aircraft land near the end of the runway with insufficient distance in which to stop.

The aircraft departed the end of the paved surface to the left of the centerline and immediately started to slow down. It continued straight ahead and stopped 145 meters beyond the end of the runway, before reaching the approach lighting for Runway 09. The captain advised ATC of their position and ATC replied that the fire vehicles were on their way. Neither of the crew was injured and they carried out the After Landing and Shutdown checks, during which they discovered that the FFPS had not been withdrawn. They then disembarked the aircraft, inserted the landing gear safety pins and liaised with the RFFS. The damage to the aircraft was confined to wheels and tires. Property damage included destruction of several runway lights and supporting structures.
The Findings

The investigation determined that the aircraft was within weight and balance limits.

The airplane manufacturer provided details of the required landing distance, from a height of 50 feet, and the landing ground run for the following conditions: Aircraft landing weight: 36,506 pounds; flap setting: 22.5 degrees; runway slope: 0.65 percent downhill; runway condition: wet asphalt; temperature: +10ýýC; pressure altitude: +640 feet; wind velocity: 230 degrees/20 knots (15-knot headwind component). These conditions provided the following landing distances:

Landing distance required (unfactored), 630 meters (2,066 feet)

Landing distance required (factored), 1,052 meters (3,450 feet)

Landing ground run distance (unfactored), 365 meters (1,196 feet)

(The factored landing distance required includes a safety margin of an extra 67 percent.)

Historical calculations have shown that if the propellers remain in flight fine pitch after landing, then the landing ground run distance is increased by the order of 10 percent, a distance of 401 meters (1,315 feet) in this case. This unfactored figure does not contain allowances for operational circumstances, such as the actual runway friction coefficient, the amount of braking used by the pilot or when it was applied.

The HS 748 has brake antiskid and gets additional braking from flap drag and the drag of suitably angled propeller blades. During the landing run the FFPS is removed to allow the blade pitch angle to “fine off” to the Ground Fine Pitch Stop (GFPS) and this creates additional drag to assist in decelerating the aircraft. Amber-colored warning lights for BELOW FFPS and FFPS REMOVED are located on both the left and right flight instrument panels. An audible horn sounds if the FFPS is not withdrawn within five seconds of the nosewheel being on the ground during the landing roll. This is the same horn as the undercarriage indication horn, and the horn will cancel once the FFPS has been withdrawn.

Runway 27 is 1,463 meters (4,800 feet) in length and 45 meters (147.6 feet) wide. Its overall slope, which is not uniform, is published as being 0.65 percent down. The threshold of the runway is at an elevation of 334 feet msl. Its surface is asphalt except at the thresholds where the surface is concrete. The runway is equipped with high-intensity coded centerline lights and five crossbar approach lights, PAPIs set at three degrees and high-intensity threshold lights with high-intensity wing bars. At the time of the incident these were selected to 100 percent intensity. The runway has 17 elevated high-intensity white bidirectional edge lights, with low-intensity omnidirectional components at 60-meter intervals, and high-intensity color-coded centerline lights and red end lights. These were selected ON to an intensity setting of 100 percent.
A Look at Management

During the CAA Annual Audit in February 2004 of the carrier, one of the non-conformances that was raised was: “The CRM training observed did not meet an acceptable standard.” This required remedial action within 30 days. The CAA’s AOC Annual Report on the operator in March 2004 included the comment that: “A further period of close supervision will be required. . . .”

After the CAA’s Annual Audit of the operator in January 2005, the CAA commented that: “The operator’s management structure must be suitable for the scale and scope of the operation – this includes adequate oversight by post holders of their areas of responsibility. The operator should review management competencies and terms of reference when addressing these non-conformances.” In April 2005, the CAA noted that the agency had expended “considerable efforts with this operator but must continue monitoring closely while they [the operator] are reducing fleets and remain under financial pressure.” The records also showed that the operator had had 27 serious incidents in the year 2004-2005.

Following a serious incident involving one of the operator’s British Aerospace ATP aircraft on May 23, 2005, the AAIB’s Aircraft Accident Report found that, “The flight crew did not comply with Standard Operating Procedures [SOPs] regarding checklist use and crew coordination.” After a further CAA audit in August 2005, it was noted that, “The findings . . . were an indication of a lack of control and supervision of the operation by the management and their ability to fulfill their responsibilities in respect of: the monitoring of flight safety standards; the allocation of responsibilities and duties and issuing instructions to individuals, sufficient for implementation of company policy and the maintenance of safety.”

In March 2006, the CAA carried out an audit of the operator’s flight crew training, across all their fleets. One of the nonconformances raised stated, “There was no oversight of the standards of the training and checking by the operator, as evidenced by the TRE’s lack of knowledge of SOPs.” As a result of this audit, the CAA restricted the operator’s AOC to six months validity and removed approval of the operator’s recurrent training and checking program, required under JAR-OPS 1.965(a)(2), pending a suitable action plan, by April 10, 2006, to address the systemic failures identified by the audit.

The operator could not satisfy the CAA that it was able to appreciate the underlying causes of the systemic failures and put into place effective remedial action. Consequently, the CAA concluded that the operator was unable to secure a safe operation. Therefore, on May 4, 2006, the agency suspended the operator’s AOC. The company effectively ceased business and its operator’s AOC was revoked on Aug. 7, 2006.
The Investigators’ Analysis

Flight crew procedures outlined in Emerald’s Operations Manual stipulated the standard altimeter calls to be used by the flight crew. They were consistent with industry standards. The problem was that the trainers and crews didn’t understand them or practice them regularly. What follows is the investigators’ analysis.

The weather conditions at Guernsey, of which both pilots were aware, were acceptable for a Category I ILS approach to Runway 27. The aircraft was suitably equipped and the pilots were both properly qualified for the flight. The aircraft, which was free from defects, was 2,945 kilograms below its maximum landing weight at the time of the incident. At that weight, the LDR of 1,052 meters was well within the LDA of 1,453 meters. The unfactored distance required for the aircraft to stop after touching down was also within the estimated 400 meters to 550 meters of runway remaining, assuming that the aircraft was able to achieve the average performance of an HS 748 Series 2A when flown in accordance with the required technique. However, the aircraft failed to stop and overran the end of the runway.

Due to the lack of FDR data, it was not possible to determine the touchdown point from the recorded data with accuracy. However, the aircraft was still 50 feet above the runway when the EGPWS recorded a GPS position that was 596 meters beyond the start of the 1,463-meter runway.

This information, coupled with eyewitness accounts, radar data and CVR timing, indicate that the airplane touched down between 400 and 550 meters before the end of the runway. Factoring the wind into the radar-derived groundspeed, the aircraft final approach airspeed averaged 113 knots over the last minute, above the minimum threshold figures stated by the crew during the approach checks.

The aircraft touched down in wind conditions that were within limits for landing on a wet runway and the overall friction level for the runway was greater than that required by the airport maintenance planning level. There was some evidence on the tire on the No. 4 wheel, corresponding to witness marks on the concrete surface at the stop end of Runway 27, that it may have hydroplaned over a short distance. Overall, the tire marks at the end of the runway and the flattened heated area on the No. 4 tire did appear to be consistent with a locked wheel on a wet runway, a condition associated with hydroplaning. Investigators estimated that the aircraft ran off the runway at a speed of about 50 knots, a speed that is below the 75-knot typical threshold for hydroplaning this aircraft.

With the lack of any other defects found during the post-incident inspections, and no reported problem with the aircraft’s performance on the landing after the ferry flight back to the U.K., it is concluded that there was no evidence that a technical problem with the aircraft contributed to this incident.

Investigators concluded the aircraft was satisfactorily established on the ILS localizer and glideslope for the final approach to Runway 27 and was correctly configured for a landing. However, the procedure briefed by the captain for the challenge and response callouts during the approach, and those used during the flight, differed significantly from those stipulated in the Operations Manual. This appears to have created a confused decision-making process as the aircraft approached the DA. In response to one of the calls from the copilot near the end of the approach, the captain indicated that he was going to continue the descent, as if the copilot might be expecting otherwise. The copilot commented that there was still farther to go to their decision (emphasis BCA’s).

The crew continued the approach until they heard the call “Minimums, minimums,” which was triggered by the setting of the bug on the radio altimeter. This was contrary to the procedures laid down in the company Operations Manual regarding use of the radio altimeter during an ILS. The PF then asked the PNF whether he was visual, as opposed to the SOP in which the PF should have called “Decide,” to which the PNF should have responded “Land,” or “Go around,” depending on whether or not he could see the necessary visual references.

Having established visual contact with the runway, the captain recalled seeing the aircraft’s left wingtip over the right edge of the runway when he first became visual with the approach and runway lights. This indicated a lateral displacement of about 37 meters to the right of the runway centerline, which was still within the criteria for “one dot” displacement on the localizer display at the point of the DA. However, the captain’s description of the aircraft’s position suggests that it was much nearer the runway threshold than it would normally be at the DA if it was on the ILS glideslope, namely a distance of some 852 meters short of the runway threshold (1,152 meters short of the runway touchdown aiming point).

The delay in making the decision to land, followed by reduction in the rate of descent while the aircraft was maneuvered to the left, over the downward sloping portion of the runway surface, resulted in the aircraft landing beyond touchdown zone and over halfway down the runway. It had been observed by personnel in the ATC tower cab that the aircraft was still airborne, at a height of about 50 feet, with approximately 730 meters of runway remaining.

After landing, possibly yawed to the right, the captain switched on his windscreen wipers, called for “Locks” and applied the brakes, while also correcting the yaw. The copilot attempted to engage the control locks, but was prevented from doing so by the interlock with the FFPS, which remained engaged. This is contrary to the SOP in which the PF should call for the withdrawal of the FFPS immediately after landing and, having done so, the PNF should respond with the information that the six appropriate lights have come on, or not, as the case may be.

Not withdrawing the FFPS after touchdown reduced the rate at which the aircraft decelerated, thereby increasing the landing ground roll. Being unaware that they had departed from the SOP, the crew may have attributed the aircraft’s slow deceleration to some other cause, such as aquaplaning. In releasing and reapplying (“cycling”) the brakes the aircraft’s ground roll would have been increased still farther. It could also not be determined how rapidly and heavily the captain applied the brakes immediately after touchdown, before he realized that the aircraft was farther down the runway than he had initially thought and applied maximum braking.

The captain, a TRE and IRE, was more experienced, better qualified and older than the copilot, who was in his first six months in the company. This created a steep “cockpit gradient” in which non-standard procedures were more likely to survive if they were initiated by the more senior of the two pilots.

The captain had been assessed as exceptional by the operator during recent recurrent training. This was likely to have encouraged his confidence in his procedures, techniques and ability. In addition, it would have taken confidence and discipline for the relatively inexperienced, newly joined copilot to challenge the procedures and technique being used by an experienced training captain who had been in the company for 11 years.

The fact that the aircraft ahead of them, a DHC-8, had landed successfully may have boosted their expectation that they, too, would be able to land in the weather conditions that existed at the time.
What’s to Be Learned?

This accident can be a good case for hangar flying. How does your department shape up? Do your approach calls work for you? Do you follow your SOPs for stabilized approaches and missed approaches all the time? Do you take special care when you are paired with a new team member or, perhaps, with a department manager who doesn’t fly the line all that often? Good stuff to think about.

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  1. Hi there, its fastidious piece of writing concerning media print, we
    all understand media is a great source of facts.

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