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.
Antiskid System Failed
Beech Premier 1A. Destroyed. Five fatalities, two serious injuries.
Affected by an acute sleep loss and inadequate knowledge of the business jet’s systems, the pilot did not react to an indication that the antiskid braking system had failed, according to investigators. He continued the approach but likely realized shortly after touchdown that he would not be able to bring the airplane to a stop on the runway.
The pilot attempted to go around but neglected to retract the landing gear and the wing lift-dump system (spoilers). Struggling to climb, the airplane struck a utility pole and crashed, killing all five passengers and seriously injuring the pilot and copilot.
The accident occurred the night of Feb. 20, 2013, during a business flight from Nashville, Tennessee, U.S., to Thomson, Georgia. During the flight, the copilot cautioned the pilot that he was “blowing through” an assigned altitude and reminded him to adjust his altimeter setting.
“The pilot responded to the altimeter reminder by stating, ‘Say, I’m kind of out of the loop or something. … I appreciate you looking after me,’” said the report by the U.S. National Transportation Safety Board (NTSB).
Investigators determined that the pilot likely was suffering from fatigue. He had slept only five hours early the previous night and had received only about four hours of rest, interrupted by several telephone calls, during the subsequent 18 hours preceding the accident.
Night visual meteorological conditions (VMC) prevailed at Thomson-McDuffie County Airport, and the pilots conducted a visual approach to Runway 10. Shortly after the landing gear was extended, the “ANTI SKID FAIL” annunciator illuminated. The copilot called out the warning to the pilot.
“The pilot continued the approach,” the report said. “He did not respond to the copilot and did not refer to the abnormal procedures … checklist to address the antiskid system failure message.”
The airplane’s flaps had been extended to 30 degrees for the approach, a configuration that is not authorized for landing with the antiskid system inoperative. “According to the checklist, the pilot should move the antiskid switch to ‘OFF’ and plan for a flaps-10 or flaps-up landing,” which increase landing distance by 130 percent and 89 percent, respectively, the report said. However, in either of the approved configurations, the Premier’s required landing distance exceeded the 5,208 ft (1,587 m) available for landing on Runway 10.
About seven seconds after touchdown, the pilot initiated a go-around. Although neither pilot later could recall the reason for the go-around, “it is likely that the pilot recognized that the airplane was not slowing as he expected and might not stop before the end of the runway,” the report said.
The airplane lifted off near the end of the runway and was about 63 ft above the ground when the left wing struck a 72-ft (22-m) concrete utility pole about 1,835 ft (559 m) from the departure threshold. The flaps were in transit, but the landing gear and spoilers were still extended on impact. “The airplane continued another 925 ft [282 m] before crashing in a wooded area” at 2006 local time, the report said.
Although the seat belt sign was illuminated and the chime was sounded during approach, none of the passengers had their seat belts or shoulder harnesses fastened. They succumbed to multiple traumatic injuries, the report said.
The report noted that the utility pole was among several that did not meet U.S. Federal Aviation Administration (FAA) airport-obstruction standards; the utility company had not notified the FAA, as required, before erecting the poles in 1989.
The NTSB concluded that the probable causes of the accident were “the pilot’s failure to follow airplane flight manual procedures for an antiskid failure in flight and his failure to immediately retract the lift-dump after he elected to attempt a go-around on the runway.” The report said that contributing factors were “the pilot’s lack of systems knowledge and his fatigue due to acute sleep loss.”
Struck by Lightning
Embraer 145LR. Minor damage. No injuries.
Significant convective activity prevailed along the regional jet’s route from Dallas–Fort Worth (Texas, U.S.) International Airport to Madison, Wisconsin, the evening of Jan. 24, 2012. The airplane encountered thunderstorms shortly after departing with 50 passengers and three crewmembers.
“The [flight] crew attempted to identify areas where they could divert to avoid the convective activity, but the controller was unable to approve significant deviations because of other traffic flows in the vicinity,” the NTSB report said.
About 15 minutes after takeoff, while discussing the possibility of turning back to Dallas–Fort Worth, the airplane was struck by lightning. The crew declared an emergency and requested clearance to divert to Little Rock, Arkansas. The controller immediately approved the request.
“After landing, the airplane was inspected and found to have sustained damage from the lightning strike requiring repairs to the left wing skin and rivets, and replacement of the left wing tip and aileron,” the report said.
The incident was included as an example in a subsequent recommendation by NTSB that the FAA improve the transmission of real-time lightning data to controllers and pilots.
Gulfstream GV-SP. Substantial damage. No injuries.
Day VMC prevailed when the Gulfstream departed from Appleton, Wisconsin, U.S., on Feb. 14, 2011, for a post-maintenance test flight. After conducting a landing and a low approach at nearby airports, the flight crew returned to Appleton for a landing on Runway 30, which is 6,501 ft (1,982 m) long.
The GV was on final approach when an amber caution light illuminated, indicating low fluid quantity in the left hydraulic system. Subsequently, the left hydraulic system failure warning light illuminated.
“The pilot not flying (PNF) pulled out the checklist to accomplish the left hydraulic system failure procedures and then suggested a go-around because the landing runway was about 500 feet [152 m] shorter than the recommended minimum runway length indicated in the checklist,” the NTSB report said.
However, the pilot flying (PF) decided to continue the approach. “Both the PF and PNF thought the auxiliary hydraulic system could support normal spoilers, brakes and nosewheel steering,” the report said.
After touchdown, the PF deployed the operative thrust reverser on the right engine and applied manual braking. However, he perceived no braking action and initiated a go-around.
The PNF saw the indicated airspeed stagnate at 100 kt and felt no acceleration, so he pulled the throttles back to reject the go-around. The PF then deployed the right thrust reverser again in attempt to slow the airplane.
The landing gear collapsed and the left wing was substantially damaged after the GV overran the runway at about 95 kt, but the pilots and their passenger were not injured. Examination of the airplane revealed a hydraulic leak emanating from a fractured connecting tube on the nose landing gear swivel assembly. The assembly was found to be misaligned, resulting in wear and eventual seizure.
Stall During a Go-Around
Beech King Air E90. Destroyed. Two fatalities.
The 1,100-hour private pilot had owned a Cessna 414 piston twin before purchasing the King Air and had received about 58 hours of dual instruction in the twin-turboprop. He had not flown for two months before departing with his flight instructor from Marana, Arizona, U.S., the morning of Feb. 6, 2013. He told a line service worker that they were “going out to practice for about an hour,” the NTSB report said.
A witness who later saw the airplane approaching Runway 05 at the airport in Casa Grande, Arizona, recalled that it pulled up into vertical flight, banked left, pitched nose-down and then struck the ground.
“It is likely that the pilot was attempting a go-around, pitched up the airplane excessively and subsequently lost control, which resulted in the airplane [stalling and] impacting flat desert terrain about 100 feet [30 m] north of the active runway at about the midfield point in a steep nose-down, left-wing-low attitude,” the report said. “A post-accident examination of the airframe and both engines revealed no anomalies that would have precluded normal operation.”
Toxicological testing revealed the presence of tetrahydrocannabinol in the flight instructor’s body, at levels indicating that he “most recently used marijuana at least several hours before the accident,” the report said. “However, the effects of marijuana use on the flight instructor’s judgment and performance at the time of the accident could not be determined.”
Fairchild Metro III. Substantial damage. No injuries.
The flight crew was conducting a functional check flight the night of Feb. 15, 2012, following the completion of maintenance work on the left engine fuel flow indicating system at Brisbane, Queensland, Australia.
After takeoff, the crew maneuvered the aircraft for an instrument landing system (ILS) approach to Runway 19. The report by the Australian Transport Safety Bureau (ATSB) did not specify the prevailing weather conditions.
“Upon selection of the landing gear handle to the down position, there were no indications or sounds to indicate that the landing gear had extended,” the report said. After receiving clearance from air traffic control (ATC) to enter a holding pattern, the crew consulted the quick reference handbook (QRH).
Activation of the emergency landing gear release lever resulted in sounds of increased airflow but no indications that the gear was down and locked. The pilots then attempted to manually extend the gear but were able to cycle the hand pump only a few times before it resisted further movement.
The crew proceeded to an “additional procedure” recommended by the QRH. “This procedure required the crew to reduce airspeed to just above the flight idle speed, cycle the gear handle and then return the system to the emergency extension mode,” the report said. “The crew reported that these actions were carried out but the landing gear did not extend.”
Consulting by radio with maintenance personnel, the pilots “cycled the gear handle while conducting a series of aircraft manoeuvres in an attempt to force the gear to extend due to in-flight loading,” the report said. These actions also were unsuccessful in extending the gear, as confirmed by maintenance personnel during low passes over the runway.
The crew then confirmed that the landing gear was fully retracted and conducted a wheels-up landing according to the QRH, shutting down both engines and feathering the propellers before touchdown. The Metro skidded to a stop on two propeller blades on each engine and a tail-mounted navigation antenna.
Investigators found that an electrical wire on the landing gear selector had separated from a connector, preventing normal operation of the gear. “The investigation also identified an out-of-rig condition in the landing gear emergency extension system, which prevented correct operation of that system,” the report said.
Prop Strikes Jet Bridge
Embraer Brasilia. Minor damage. No injuries.
The captain was focusing his attention on the marshaller, and the first officer was looking out the right side window to ensure clearance between the wing and a parked fuel truck as the airplane was taxied to the gate at Los Angeles International Airport the morning of Feb. 16, 2010.
“The marshaller reported that he was concentrating on the airplane’s right side … and was concerned about the [fuel] truck’s proximity to the airplane,” the NTSB report said. “Because of where his attention was focused, he misjudged the stop line marked for EMB [Embraer] airplanes and instead signaled the airplane to stop on the line marked for [Bombardier] CRJ airplanes.” The markings were about 18 ft (5 m) apart.
Just as the marshaller was crossing his wands to signal the pilots to stop the airplane, the left propeller struck the jet bridge. Two of the four blades dented the jet bridge and shed fragments that damaged the airplane’s fuselage and left engine nacelle.
“An oil spray residue was observed on the left side of the fuselage, and a pool of oil was present below the left engine and wing,” the report said. The damage was characterized as minor. None of the three people aboard the airplane, nor the marshaller, was injured.
Noting that the captain would have been able to see part of the left engine and propeller as the airplane neared the jet bridge, the NTSB said that the probable cause of the incident was “the flight crew’s failure to maintain clearance from the jet bridge during taxi.” The report said that a contributing factor was “the ramp marshaller’s diverted attention and failure to signal the flight crew to stop at the correct position.”
Fire on Takeoff
Convair 440-38. Destroyed. Two fatalities.
VMC prevailed when the airplane departed from San Juan, Puerto Rico, the morning of March 15, 2012, for a cargo flight to Saint Martin, Netherlands Antilles. Shortly after takeoff from Runway 10, the flight crew declared an emergency and requested a left turn to return to Luis Muñoz International Airport.
ATC approved the request and cleared the crew to land on Runway 28. The crew asked if the controller saw smoke; the controller said that he did not see smoke coming from the airplane.
“Radar data shows that the airplane was heading south at an altitude of about 520 ft when it began a descending turn to the right to line up with Runway 28,” the NTSB report said. “The airplane continued to bank to the right until radar contact was lost.”
Both pilots were killed when the Convair struck trees and crashed in a lagoon about 1 nm (2 km) east of the approach end of Runway 28.
Investigators estimated that airspeed was about 88 kt — 9 kt below stall speed in level flight and 1 kt above the minimum control speed with one engine inoperative — when ATC lost radar contact with the airplane. “However, minimum control speeds increase substantially for a turn into the inoperative engine, as the accident crew did in the final seconds of the flight,” the report said.
Examination of the wreckage revealed signs of an in-flight fire that erupted in the vicinity of the junction between the augmentor assemblies and the exhaust muffler. The source of ignition was not determined.
The examination also revealed that the right engine had been shut down but the propeller had not been feathered, and that the left propeller had been feathered although the engine controls remained set for takeoff.
“The accident airplane was not equipped with a flight data recorder or a cockpit voice recorder (nor was it required to be so equipped),” the report said. “Hence, the investigation was unable to determine at what point in the accident sequence the flight crew shut down the right engine and at what point they feathered the left propeller, or why they would have done so.”
The switch for the autofeather system, which would have feathered the propeller on the engine losing power and prevented the propeller on the operating engine from feathering, was found in the “OFF” position. Interviews with company pilots indicated that the captain generally did not use either the autofeather system or the engine antidetonation (water-injection) system.
The report said that, on takeoff, the airplane was about 6,800 lb (3,084 kg) above the authorized maximum gross takeoff weight with the autofeather and antidetonation systems inoperative.
The NTSB concluded that the probable cause of the accident was “the flight crew’s failure to maintain adequate airspeed after shutting down the right engine due to an in-flight fire in one of the right augmentors, [which] resulted in either an aerodynamic stall or a loss of directional control.”
Beech 58 Baron. Substantial damage. No injuries.
Shortly after the Baron touched down on the runway at Rustenburg, South Africa, the morning of Feb. 13, 2014, the landing gear collapsed. The propeller blades, the engines and the lower fuselage skin were damaged as the aircraft slid to a stop, but none of the four occupants was injured.
“The investigation found that the accident occurred because the pilot was attempting to put the flaps control ‘UP’ after landing and moved the landing gear control instead,” said the report by the South African Civil Aviation Authority (CAA).
“The inadvertent movement of the landing gear control was attributed to the pilot’s being more accustomed to flying aircraft in which these two controls were in exactly opposite locations,” the report said.
Eurocopter MBB-BK117. Minor damage. No injuries.
The helicopter encountered light to moderate turbulence and a tail wind shortly after departing from Port Pirie, South Australia, for a medevac flight to Adelaide, South Australia, the afternoon of Feb. 15, 2013.
About 12 minutes after takeoff, the helicopter abruptly pitched nose-up and rolled left. The helicopter descended from 5,000 ft to about 800 ft before the pilot regained control. The crew returned to Port Pirie and landed without further incident.
ATSB investigators found that the helicopter’s high gross weight and high airspeed, along with the turbulence and high density altitude, were conducive to the onset of a retreating-blade stall. “The pilot’s instinctive action of pushing the cyclic control forward delayed recovery from the stall,” the report said.
Robinson R44. Substantial damage. No injuries.
The siren-equipped helicopter departed from Setlakgole, South Africa, for a game-culling flight the morning of Feb. 12, 2014. The pilot said that the helicopter was being flown at 40 kt and about 200 ft above the ground when the engine lost power about 35 minutes after takeoff.
The pilot landed the helicopter straight ahead in dense brush. The R44 touched down hard, and the tail rotor blades struck and severed the tail boom. The pilot and his passenger were not hurt.
“Post-accident investigation did not identify any defects of the engine which could have contributed to the accident,” said the report by the South African CAA, which concluded that the pilot had inadvertently disengaged the hydraulic system in flight. The CAA’s report noted that the switches for both the hydraulic system and the siren are mounted on the cyclic.