The following information provides an awareness of problems that might be avoided in the future. The information is based on final reports by official investigative authorities on aircraft accidents and incidents.
Hard Touchdown on Runway
Airbus A319-111. Substantial damage. No injuries.
A hard touchdown that destroyed the A319’s landing gear resulted in part from an initial nose-down sidestick input by the pilot flying (PF) that was not countermanded by the commander’s application of nose-up sidestick during the initiation of a go-around at London Luton Airport the afternoon of Feb. 14, 2012, said the U.K. Air Accidents Investigation Branch (AAIB).
The aircraft became airborne after the brief touchdown, and the flight crew completed the go-around and landed without further incident. There were no injuries among the 142 passengers and six crewmembers, but the force of the hard landing exceeded the maximum certified loads on the aircraft’s main landing gear, and the gear had to be replaced.
The A319 was inbound from Faro, Portugal. A captain-under-training was flying the aircraft from the left seat. He had 3,998 flight hours, including 672 hours in type. The report noted that he had completed “nine sectors of command training without notable incident, and the training reports prior to the event had all been positive.” His command training had included practice in the “TOGA 10” go-around procedure, which includes takeoff/go-around (TOGA) power and a 10-degree pitch attitude, in flight simulators, but he had not conducted the procedure in an A319.
The commander, a training captain, had 10,700 flight hours, including 500 hours in type. “The commander had previous experience of line training on another aircraft type but was relatively inexperienced in this capacity on the Airbus 320-series aircraft,” the report said. Like the trainee captain, the commander had practiced the TOGA 10 procedure in simulators but had not conducted the procedure in an A319.
Luton had clear weather and surface winds from 320 degrees at 16 kt. The crew flew a standard arrival procedure that took the aircraft north of the airport and then received radar vectors from air traffic control (ATC) to position the aircraft for the instrument landing system (ILS) approach to Runway 26. “The crew were aware that some turbulence can be expected on the final approach to Runway 26 when the wind is from the northwest,” the report said.
Nearing the airport from the north, “the aircraft was given an early radar vector towards the final approach track, and the PF increased the rate of descent,” the AAIB report said. “The aircraft was then allocated a heading of 220 degrees, cleared to intercept the localiser and, once established, to descend on the glidepath.”
Preparing to capture the ILS glideslope from above, the PF called for the “flap 2” setting and for extension of the landing gear. He armed the electronic flight control system’s localizer mode and then inadvertently selected the expedite mode rather than the approach mode. “The expedite mode is used in climb or descent to reach the desired altitude with the maximum vertical gradient,” the report said. “The expedite climb mode engaged, but, to prevent a climb or any mode confusion and to regain the correct profile, the PF disconnected the autopilot and the autothrust.”
During this time, the A319 had flown through the localizer course. ATC issued a heading to enable the crew to re-intercept the localizer.
The PF elected to continue hand flying the approach. The aircraft was established on the localizer course about 6 nm (11 km) from the runway. “The wind conditions were gusty and gave rise to some turbulence on the approach,” the report said.
Recorded flight data showed that the approach remained stabilized until the aircraft was close to the runway. “Below 30 ft over the runway, both pilots sensed that the aircraft was sinking rapidly, and both initiated a TOGA 10 go-around,” the report said. “The PF momentarily retarded the thrust levers to idle before advancing them to the TOGA position. At the same time, he made a full-forward sidestick input, within one second, which was then rapidly reversed to full-aft sidestick.”
The report said that a possible explanation for the PF’s initial aft movement of the thrust levers and forward input on the sidestick was “momentary confusion between the actions of his left and right hands.”
As the PF made the forward sidestick input, the commander made a full-aft input, pushed the thrust levers full-forward and announced, “I have control.” However, the commander had not engaged the “takeover” pushbutton on his sidestick. Thus, flight-control priority remained with the PF, and the commander’s nose-up sidestick input only reduced the magnitude of the nose-down input made by the PF.
“If the commander had used the sidestick takeover pushbutton, the severe hard landing may have been prevented,” the report said.
The report noted that Airbus sidesticks move independently, “so one pilot may not be aware of a control input being made by the other.” A small green light illuminates on the glareshield in front of the pilot who has priority control. If both sidesticks are moved at the same time, without activation of the takeover pushbutton by the other pilot, both green lights illuminate and an aural “dual input” message is generated.
The report noted that although “a pilot can deactivate the other stick and take full control by pressing and keeping pressed his priority takeover pushbutton … the use of the takeover pushbutton has been shown from previous incidents not to be instinctive.”
The simultaneous sidestick inputs of 15 degrees forward by the PF and 8 degrees aft by the commander had resulted in a momentary net input of 7 degrees forward before both pilots applied full-aft inputs. The A319 touched down on all three landing gear a half second later.
A “load report” generated automatically by the aircraft after the hard, three-point touchdown showed that the rate of descent was 12.5 ft/second and that vertical acceleration was 2.99 g (2.99 times standard gravitational acceleration). Because of these parameters, the event was classified as a “severe hard landing,” the report said. Analysis of the recorded data by Airbus indicated that several components of the landing gear had exceeded design load limits and required replacement. No other aircraft damage was found.
Early Rotation Damages Tail
Boeing 737-800. Substantial damage. No injuries.
Performance data for a takeoff from Runway 25R, the runway in use at Los Angeles International Airport (LAX) the morning of Jan. 3, 2011, had been loaded automatically into the 737’s flight management system (FMS) via the aircraft communications addressing and reporting system. However, shortly before leaving the gate, the flight crew was told that the departure runway had been changed to Runway 07L.
The airplane’s takeoff performance system enables data to be automatically loaded for the first four runways listed in the database for a particular airport. Because Runway 07L was not among the first four listed for LAX, the first officer had to manually enter the takeoff data, using information in the preflight paperwork, said the report by the U.S. National Transportation Safety Board (NTSB).
Among the parameters appropriate for the conditions, the “takeoff decision speed” (V1) and the rotation speed (VR) were both 153 kt. However, the first officer inadvertently entered 123 kt for V1 and 153 kt for VR into the FMS. “The most likely reason for the inappropriate V1 value was determined to be a keystroke entry error by the first officer when manually entering data,” the report said.
When airspeed reached 123 kt on takeoff, an automated callout of V1 was generated and the captain began to rotate the airplane. “V1 and VR are typically close in value for a 737, so the captain may have reacted to the erroneous V1 callout, expecting that the airplane was also at VR,” the report said. “Had the captain waited for a ‘VR’ callout by the first officer, the erroneous V1 entry would have had no effect.”
The first officer told investigators he had noticed that the automated V1 callout had occurred too early and that the captain had begun rotation but said nothing to the captain for fear of causing confusion, the report said.
“The airplane pitched up to about 11 degrees just prior to liftoff at 148 knots,” the report said. “The airplane operating manual specifies that tail contact will occur at 11 degrees of pitch if still on or near the ground.”
Flight attendants notified the flight crew that a tail strike had occurred. The pilots completed the quick reference handbook procedure for a tail strike and decided to continue to flight to the destination, Toronto, where the airplane was landed without further incident.
The 737 was ferried to a maintenance facility, where examination of the airframe revealed substantial damage to the aft pressure bulkhead and the tail skid.
Reversed Off an Embankment
Boeing 737-200. Substantial damage. No injuries.
After deplaning their 97 charter passengers at Hoedspruit (South Africa) Air Force Base the night of Jan. 10, 2011, the flight crew prepared for the return positioning flight to Johannesburg.
The captain told investigators that visibility was poor, with intermittent rain. “Whilst taxiing to the cleared holding point for takeoff, the pilot switched off the landing lights to avoid blinding [the crew of an aircraft on final approach],” said the report by the South African Civil Aviation Authority. “As a result, he overshot the turning point in the darkness and found himself at the end of the taxiway with insufficient space to turn around.”
The captain explained the situation to ATC and requested ground assistance but was told that no equipment was available to tow the 737. He decided to turn onto a perpendicular taxiway leading to military aircraft hangars, stop and then use reverse thrust to back the 737 onto the main taxiway, facing the other way.
“This was done without external guidance,” the report said. “Whilst reversing the aircraft, the pilot failed to stop it in time; the main wheels rolled off the edge of the taxiway, and the aircraft slipped down a steep embankment, coming to rest with the nosewheel still on the taxiway. The aeroplane was substantially damaged, but no one was injured.”
Thrust Asymmetry Causes Excursion
Cessna Citation 501. Destroyed. Five fatalities.
The pilot was conducting a private flight with four passengers from Venice, Florida, U.S., to Macon County Airport in Franklin, North Carolina, the afternoon of March 15, 2012. The NTSB report noted that the pilot was not familiar with the airport, which is at 2,020 ft and surrounded by mountains.
The pilot held a private license with multiengine and instrument ratings, and a type rating in the Citation I/SP, which is certified for single-pilot operation. He had about 1,159 flight hours, including about 185 hours flown in the Citation during the previous two years.
The uncontrolled airport had clear skies, with surface winds from 260 degrees at 3 kt. Witnesses said that the Citation was high on approach to Runway 25, which is 5,001 ft (1,524 m) long and 75 ft (23 m) wide. The pilot initiated a go-around and positioned the airplane for another approach.
“During the second approach, the airplane was high again, and the approach angle steepened, nose-down toward the runway,” the report said. “The nose gear touched down approximately halfway down the runway, followed by main gear touchdown. The airplane then bounced, and the witnesses heard the engine noise increase. It then banked right, and the right wing contacted the ground. The airplane subsequently flipped over off the right side of the runway, and a post-crash fire ensued.” All five occupants were killed.
Examination of the Citation revealed that the thrust reverser on the right engine was deployed and the thrust reverser on the left engine was stowed on impact. “The airplane had already porpoised and bounced during the landing,” the report said. “The pilot’s subsequent activation of only the right engine’s thrust reverser would have created asymmetric thrust and most likely exacerbated an already uncontrolled touchdown.”
Eight Minutes of Silence
Boeing 757-200. No damage. No injuries.
The flight crew did not activate the 757’s transponder before taking off on Runway 27R at Hartsfield–Jackson Atlanta International Airport the afternoon of March 11, 2011, for a flight to New York with 130 people aboard. About a minute after departure, the airport traffic controller told the crew to establish radio communication with the departure controller. The crew acknowledged the instruction but did not contact the departure controller for eight minutes.
“The airplane flew through one controller’s airspace and entered another controller’s airspace without coordination before radar and radio contact were established,” the NTSB report said, noting that the airport controllers had not verified that there was a radar data tag for the 757 before handing off the flight to the departure controllers. The airplane appeared on radar only as an enhanced primary target, with no identification, altitude or airspeed data.
A review of primary radar data revealed that a loss of required lateral separation had occurred with three other airplanes: The 757 had passed within 0.8 nm (1.5 km) of a Pilatus PC-12, 1.4 nm (2.6 km) of a Beech Baron and 2.4 nm (4.4 km) of a Bombardier CRJ100.
Ice Suspected in Control Loss
ATR 42-300. No damage. No injuries.
While preparing for the return flight from Bergen to Floro, both on the west coast of Norway, the flight crew noticed that snow was accumulating on the aircraft and that there were remnants of clear ice on the wings, horizontal stabilizer and propeller spinners that had accumulated during the earlier flight in moderate icing conditions that included freezing sleet.
After the 24 passengers were boarded, the ATR 42 was deiced with warm water and sprayed by two vehicles with 69 L (18 gal) of Type 2 anti-icing fluid at 100 percent concentration. In addition, 17 L (4 gal) of Type 1 anti-icing fluid at 28 percent concentration were applied to the bottom of the horizontal tail surfaces.
The holdover time — basically, the time at which the deicing/anti-icing procedure would have to be repeated — was 30 minutes, said a report on the Nov. 9, 2007, incident issued in January 2013 by the Accident Investigation Board Norway (AIBN).
The crew initiated the takeoff eight minutes after the deicing/anti-icing procedure was completed. Airspeed was 10 kt below the calculated rotation speed when the aircraft lifted off the runway without any control inputs by the pilots.
“According to the commander, the aircraft continued the uncontrolled ascent in spite of both control columns being moved to the full-forward position (stop) and engine power being increased,” the report said. “The stick shaker activated and the ‘cricket sound’ [aural stall warning] was heard for a few seconds while the airspeed decreased.
“Eventually, the nose of the aircraft started to come down and speed gradually increased. While the speed increased, the crew experienced that the control columns oscillated back and forth and were heavy to operate.”
The crew had begun a turn back to Bergen; but, as the flight controls became gradually easier to move, they decided to continue the flight to Floro, hand flying the aircraft rather than engaging the autopilot. The flight was completed without further incident, and an inspection of the flight controls revealed no discrepancies.
Investigators explored several factors that might have contributed to the serious incident, including an aft center of gravity, an incorrect elevator trim setting or jamming of the elevators by ice. The AIBN concluded that the most likely cause was ice contamination of the upper surface of the stabilizer.
The report noted that an analysis of the incident by the aircraft manufacturer concluded that “the event description fully matches with the behavior an ATR would have in case of an improper deicing of the horizontal stabilizer.” The manufacturer also said that the amount of Type 2 anti-icing fluid applied to the aircraft “seems to be low” and that a proper application would consist of about 120 L (32 gal).
The AIBN report noted that the recommended deicing procedure for the ATR 42 and 72 emphasizes the gap between the elevator and horizontal stabilizer. “This is to prevent the elevator from freezing, as has happened several times with this [aircraft] and aircraft types of similar design,” the report said. “The procedure also explicitly states that the upper surface of the tail must be deiced, but the AIBN still questions whether the special focus on clearance between the elevator and stabiliser … may have caused the deicing personnel to not be sufficiently attentive to the importance of also keeping the upper surface of the stabiliser and elevator completely free of ice and snow.”
Dornier 328-100. No damage. No injuries.
Nearing Norwich, England, the morning of March 22, 2012, the flight crew briefed the NDB/DME (nondirectional beacon/distance-measuring equipment) approach to Runway 09. The airport was reporting surface winds from 110 degrees at 7 kt and 4.0 km (2.5 mi) visibility in haze.
The company required that the decision to go around or to land be made 20 ft above the minimum descent altitude (MDA) on a nonprecision approach and that a go-around be initiated no later than reaching the MDA.
In this case, the commander, the pilot flying, “could see the ground and was aware of his position due to his local area knowledge” as the aircraft descended to the MDA, the AAIB report said. He did not make the required go-around/landing call before leveling the aircraft at the MDA. The aircraft was about 0.75 nm (1.39 km) south of the extended centerline when the commander gained visual contact with the runway a few seconds later. “The copilot could not see the runway, as it was obscured by the aircraft’s structure,” the report said.
The commander disengaged the autopilot and maneuvered the aircraft to line up with the runway centerline. “The commander later commented that the forward visibility during the approach was reduced as a result of flying towards the sun,” the report said. “He added that it was poor judgment on his part to fly the unstable manoeuvre after he became visual with the runway.
“The copilot [said] that he had been ‘slightly concerned’ during the manoeuvre but had confidence in the commander’s ability and so did not interject.”
The Dornier was banked about 30 degrees right when it crossed the runway threshold. It touched down firmly, and the right main landing gear broke an edge light as the aircraft veered slightly off the right side of the runway. “As the aircraft touched down, or possibly just before, the copilot called ‘go around’; this was flown by the commander without event,” the report said.
The crew then conducted the ILS approach to Runway 27 and landed without further incident. None of the 27 occupants was injured, and there was no damage to the Dornier.
Excursion on an Icy Runway
Rockwell 690C. Substantial damage. No injuries.
The pilot conducted a global positioning system approach to Runway 24 at Conrad (Montana, U.S.) Airport the morning of March 23, 2012. The uncontrolled airport had a 1,500-ft overcast, 2.0 mi (3.2 km) visibility in light snow and surface winds from 350 degrees at 4 kt.
After breaking out of the overcast, the pilot saw a snowplow on the 4,600- by 75-ft (1,402- by 23-m) runway. “Soon after the pilot spotted the snowplow, it exited the runway, and the pilot continued his approach/landing sequence,” the NTSB report said.
After touchdown, the airplane began to slide on the ice- and slush-covered runway. “The pilot stated that he should have initiated a go-around, but the airplane was never sufficiently realigned with the runway so he could safely apply go-around power,” the report said.
The airplane veered off the runway and struck a warning sign for a natural gas line that caused an 8-in (20-cm) tear in the fuselage skin. The pilot and his four passengers were not hurt.
Crossfeed Fuel Starvation
Beech E55 Baron. Substantial damage. One fatality, one serious injury.
The pilot said that the Baron was fully refueled before departing from Dickinson, North Dakota, U.S., for a personal flight to Kansas the afternoon of March 28, 2012. About two hours after takeoff, while cruising at 11,500 ft, he noticed indications of less fuel in the left main tank than in the right main tank.
“He attempted to correct the imbalance by placing the left fuel selector in the crossfeed position so that both engines would receive fuel from the right main fuel tank,” the NTSB report said.
About 15 minutes later, both engines lost power. The pilot repositioned the fuel selectors to the left main tank and the right auxiliary tank. “The left engine regained power, and the right engine began ‘surging,’” the report said. “The pilot reported that he was unable to maintain altitude with the left engine at full power.”
He reported the engine failure to ATC and diverted the flight to Broken Bow, Nebraska, which was about 20 nm (37 km) away. The Baron was on final approach and in landing configuration when the right engine lost power completely.
“The pilot did not feather the right propeller, thinking he was too close to landing to get the engine secured,” the report said. Nearing the minimum single-engine control speed, the airplane drifted right, and the pilot reduced power from the left engine in an attempt to maintain control.
The Baron descended onto an open field and came to rest inverted. The pilot sustained serious injuries, and his passenger was killed.
Marginal Weather Gets Worse
de Havilland Beaver. Substantial damage. One serious injury,one minor injury.
The pilot said that marginal weather conditions prevailed when he departed from a mining site for a charter flight to Ketchikan, Alaska, U.S., about 25 nm (46 km) northeast, the morning of March 13, 2012. Shortly after departure, visibility decreased nearly to zero in heavy snow.
“He attempted to follow the shoreline at a low altitude but was unable to maintain visual contact with the ground,” the NTSB report said. “He stated that he saw trees immediately in front of the [float-equipped] airplane and attempted a right turn toward what he thought was an open bay.”
During the turn, the right float struck a rock outcrop, and the Beaver descended into the bay. The pilot was seriously injured, and his passenger sustained minor injuries.
Deceptive Fuel Gauge
Aero Commander 500B. Substantial damage. One minor injury.
The fuel gauge indicated 120 gal (454 L) before the pilot departed from Kansas City, Missouri, U.S., for a positioning flight to Cushing, Oklahoma, the evening of Jan. 13, 2012. The airplane was cruising at 8,000 ft about an hour and 20 minutes later when the right engine began to lose power.
The pilot was attempting to restore power to the right engine when the left engine began to surge. As he turned toward Bartlesville (Oklahoma) Municipal Airport, both engines lost power. The pilot sustained minor injuries when the Aero Commander struck trees and terrain about 1.5 nm (2.8 km) from the airport.
“The pilot [said] that before he secured the airplane and turned the master battery switch off, the fuel gauge was still indicating 100 gallons [379 L],” the NTSB report said. However, investigators determined that the fuel gauge was faulty and that the airplane actually had only about 50 gal (189 L) of fuel when it departed from Kansas City.
‘Wind-Down’ on Pipeline Patrol
Agusta Bell 206B. Substantial. No injuries.
The pilot and his passenger were conducting a pipeline-patrol flight 600 ft above the ground near Perth, Scotland, the afternoon of Feb. 20, 2012, when they heard a loud bang as the JetRanger yawed left.
“The main rotor rpm decreased, and the engine was seen to ‘wind down,’” the AAIB report said. “The pilot completed a successful autorotation into a field.”
Initial examination of the engine showed that the compressor case had been breached by a failure of the axial compressor. Further examination at an approved engine-overhaul facility revealed that the failure had been initiated by a fatigue crack that caused a blade on the stage-two axial compressor rotor to fracture and separate, resulting in extensive damage to the compressor section.
Fuel Cap Strikes Tail Rotor
Robinson R22 Beta. Substantial damage. No injuries.
The flight instructor refueled the helicopter while his student performed a preflight inspection before departing from Bulverde, Texas, U.S., for an instructional flight the afternoon of March 9, 2011.
They were practicing autorotations when the R22 began to yaw left and right. The instructor took control and landed the helicopter in an orchard. “The helicopter’s main rotor contacted the ground, and the helicopter came to rest on its left side,” the NTSB report said. “During the impact, the tail boom separated into two pieces.”
Investigators determined that the fuel tank cap had not been secured properly before departure and had separated in flight, striking and damaging the tail rotor.
Unqualified for Night Flight
Aerospatiale Gazelle. Destroyed. One fatality.
Before departing from a mining site located in a valley near Keswick, Cumbria, England, the night of March 8, 2011, the pilot telephoned his partner at his home near Cockermouth and informed her that he was returning. He also asked about the weather conditions there and was told that it was “rather blustery” but with good visibility.
“There was no evidence that the pilot obtained any other meteorological briefing before the flight,” said the AAIB report, which noted that reduced visibilities and low clouds prevailed in the area, and that the pilot was not qualified, and had received no training, to fly at night. The report also noted that the flight time between the mining site and the destination was 10 minutes in good conditions; “the journey by car would have taken half an hour or less.”
No one saw the Gazelle depart from the mining site. A search for the helicopter was initiated about three hours later, after it was reported overdue by the pilot’s partner. The wreckage was found at the bottom of the valley, about 330 m (1,083 ft) from the mining site. Investigators determined that the impact had occurred at a high rate of descent.
Noting that “almost no cultural lighting” existed in the valley for some distance from the mining site and that the waning moonlight would have been obscured by cloud, the report concluded that the pilot likely had become disoriented and had lost control of the helicopter.