PRELIMINARY REPORTS
CitationJet Lost over Utah Following In-flight Breakup
Cessna Citation 525, near Cedar Fort, Utah, Jan. 18. 2016–The pilot and his wife were killed following “an airframe in-flight breakup” while the aircraft maneuvered at altitude. Shortly after departure from Salt Lake City International Airport (SLC) on a Part 91 IFR flight plan to Tucson, Ariz., the pilot told ATC he had experienced a flight management system (FMS) failure and that he needed to fly straight and climb while he tried to program the backup FMS. ATC cleared the aircraft to climb to FL310 and provided the pilot with traffic advisories and vectors around areas of light precipitation.
Soon after, the pilot declared “Mayday,” saying he was hand-flying the aircraft and having difficulties programming the backup system. The controller directed the pilot for a no-gyro turn to the left to avoid precipitation, and observed significant fluctuations in the aircraft’s airspeed on radar. The jet was last seen on radar in a right turn before contact was lost. There were no further transmissions from the airplane.
NTSB investigators noted that the wreckage path was a mile long, oriented west to east. All of the airplane’s primary flight controls were accounted for at the accident site, although at the time of publication, search crews had not yet located the aircraft’s left engine.
Weather at SLC, 28 nm NNE of the accident site, was calm with light rain five minutes before the crash, with broken cloud at 2,700 feet and overcast at 4,500 feet, temperature 3 degrees C and dew point 1 degree C.
Airframe Icing Noted After King Air Hard Landing
Beechcraft Super King Air 200, Gary, Ind., Dec. 30, 2015–According to the pilot, the aircraft encountered structural icing while operating a Part 135 non-scheduled passenger flight from Abraham Lincoln Capital Airport (SPI) near Springfield, Ill., to Gary/Chicago International Airport (GYY). The aircraft was damaged in a hard landing at GYY, but there were no injuries reported among the pilot and eight passengers.
Witnesses at SPI reported nothing unusual about the condition of the aircraft or passengers before takeoff. As the aircraft landed at GYY, one witness noticed ice along the leading edges of both wings and a fluid leak near the left main gear wheel assembly.
The aircraft was on an IFR flight plan. Daytime VMC prevailed 15 minutes before landing, with weather conditions at GYY reported as wind from 250 degrees at 7 knots, visibility 10 miles, overcast clouds at 1,300 feet, temperature 0 degrees C, and dew point -4 degrees C.
Pilot Reports ‘Flat Light Condition’ Before Terrain Collision
Cessna 208B Caravan, near Anaktuvuk Pass, Alaska, Jan. 2, 2016–The Part 135 commuter flight struck a ridge six miles southwest of Anaktuvuk Pass Airport (PAKP) in reported daytime VMC. Of the eight people on board, the pilot and four passengers sustained serious injuries, and three passengers sustained minor injuries.
The flight departed from Fairbanks International Airport (PAFA), with much of the 90-minute flight conducted at 2,500 feet msl (500 feet agl) along the John’s River. Ten miles from the airport, the pilot initiated a climb to the pattern altitude at PAKP, flying on the east side of the river valley to establish a straight-in approach to Runway 2. The aircraft subsequently struck the ridge and traveled about 300 feet before coming to rest on snow-covered tundra at 2,500 feet msl, roughly 500 feet below the ridgetop.
The pilot told investigators that although there was some ice on the windshield, the area covered by the hot plate remained clear, but that snow-covered ground and overcast skies resulted in “a flat light condition.” Reported weather at AKP shortly before the accident was light SSE wind, broken clouds at 4,400 feet and overcast at 5,000 feet with six statute miles visibility. o
FINAL
Lack of Lubrication Led to UH-1H Main Rotor Transmission Failure
Williams Helicopter UH-1H, in Grand Canyon, Ariz., Nov. 15, 2011–The pilot, who was seriously injured in the accident, told investigators the master caution warning light illuminated while he was flying at 500 feet agl in daytime VMC, followed by the low transmission oil pressure light. He maneuvered away from power lines and prepared to make an emergency landing three miles northwest of Valle Airport (40G). Ten feet above the ground and with little forward airspeed, the main rotor slowed and stopped, causing the helicopter to fall to the ground. The engine continued to operate for about 15 seconds after the hard landing.
Post-accident examination revealed discoloration around the transmission oil case near the main rotor reduction gear assembly, and localized paint peeling. Investigators did not find oil stains or residue on the transmission case. After disassembling the transmission, investigators found oil and metal debris coating the length of the rotor mast, with molten metal pieces in the upper planetary gears, ring gear and sun gear.
Medium- to high-density metallic particles were found in several passages in the transmission oil manifold. Damage was also found in the Honeywell T53-L-703 turboshaft’s first-stage compressor blades, along with metal spray on the second-stage power-turbine stator vanes. Investigators determined that lack of lubrication caused the transmission to overheat and seize.
The helicopter’s logbook indicated a 25-/50-hour inspection had been performed on Oct. 11, 2011, with an annual inspection due in November 2011. The main rotor assembly, mast and main transmission assembly had been removed in August 2011 for replacement of five mounts and installation of three new boots. Overhauled dampers were also installed on both the left and right sides of the main transmission. After reassembly, a ground run revealed no evidence of leaks.
Fast Approach Preceded G200 Runway Excursion
Gulfstream G200, Jamestown, N.Y., June 20, 2013–Following an uneventful airman competency check flight, the pilot flying (PF) and pilot monitoring (PM) configured the twinjet for a practice ILS approach and landing on 5,299-foot Runway 25 at Chautauqua County/Jamestown Airport (JHW) in daytime VMC.
Cockpit voice recordings revealed that the PM warned the PF that the approach speed was 15 knots faster than Vref as they passed through 100 feet agl. The PM further warned not to allow any more gains in airspeed, as the runway was “short.” No discussion about a go-around was noted.
The aircraft landed within the normal touchdown zone, approximately 1,000 feet beyond the runway threshold, but applying the brakes and deploying the thrust reversers failed to slow the aircraft before it continued off the departure end of the runway, coming to rest 40 feet beyond the pavement. The nose landing gear and the trailing edge of the left wing flap struck two runway end lights, inflicting minor damage to the flap.
Using the manufacturer’s Airplane Flight Manual, investigators calculated that sufficient landing distance was available for a normal landing on the dry runway. No mechanical anomalies with the brakes or thrust reversers were found; despite statements from the PF to investigators that “braking/stopping ability was nil” on landing, the CVR transcript indicated that neither pilot mentioned poor braking or attempted to engage emergency braking systems during the landing rollout.
Weather at JHW five minutes after the accident was calm with 10 miles visibility, clear sky, temperature 23 degrees C and dew point 9 degrees C.
Pressure To Save Police Dog a Factor in Helicopter Crash
Bell OH-58A, Tehachapi, Calif., Mar. 27, 2014–The NTSB determined that pilot fatigue, spatial disorientation in nighttime low IMC and pressure to save a wounded dog were all factors in the hard landing of a Kern County Sheriff’s Department helicopter. A company flight plan was filed for the VFR flight from Meadows Field Airport (BFL) in Bakersfield, Calif. to General William J. Fox Airfield in Lancaster. Tehachapi Municipal Airport (TSP) was listed as an alternate.
Investigators determined the pilot had received two hours of “restful” sleep before being called to transport a dog that had been shot on duty to the urgent-care facility in Lancaster. The pilot arrived at the Sheriff’s Air Support Unit (ASU) headquarters at 1 a.m., and preflight planning indicated that although visual conditions prevailed at the departure and arrival airports, a passing front would likely create IMC along the route of flight. The IFR-rated pilot chose to continue with the flight, although the helicopter was not equipped to operate in instrument conditions.
The helicopter encountered light rain, strong wind and low clouds while approaching Tehachapi at 500 feet agl, with an overcast cloud deck 100 feet above. The pilot lost visual reference to ground lighting shortly after passing Tehachapi but opted to continue along the route of flight, driven by concerns that turning back toward TSP might take him into a nearby wind turbine farm or other obstacles.
Both the pilot and non-pilot-rated technical flight officer (TFO) used night-vision goggles for the accident flight, but their effectiveness was hindered by windshield misting caused by a rainwater leak. The TFO eventually noticed the misting and activated the helicopter’s defogging system while looking out the side window to determine clearance from the ground.
As conditions deteriorated further, the pilot entered a slow descent in an attempt to re-establish visual contact with the ground. He did not use the helicopter’s radar altimeter. At 1:47 a.m., the helicopter struck Highway 58 five miles east of TSP, bounced back into the air and rotated about 180 degrees.
After the collision, the pilot determined the helicopter was handling normally and opted to return to TSP. After making an uneventful landing, the pilot and TFO found damage to the helicopter’s belly, nose-mounted forward-looking infrared (FLIR) camera and rear-mounted searchlight. The landing skids were splayed two feet beyond their normal dimensions.
The commercial pilot, TFO, single passenger and police dog were not injured in the accident.
Rescuer’s Rope Downed AS350 During High-Altitude Rescue
Airbus Helicopters AS350B3, near Draper, Utah, Sept. 9, 2015–Investigators determined that an improperly secured rescue rope brought down a helicopter during a high-altitude rescue mission in “remote and nearly vertical” terrain.
The helicopter’s two crewmembers were not injured in the crash, which happened as they were working with a three-person team on the ground to recover an injured hiker. As the right skid touched down on a rock outcropping, a ground rope holding one of the rescuers contacted the main rotor blades, causing the helicopter to rotate abruptly to the left and begin shaking.
The helicopter struck the ridge, but the pilot was able to recover control and subsequently made an emergency landing at a lower altitude, reporting that the helicopter began to shake violently again until it touched down and collective pitch was reduced. The main rotor system, the tail boom and the empennage suffered substantial damage.
In its probable cause report, the NTSB cited guidance published in two manuals from the U.S. National Park Service for the National Search and Rescue Academy highlighting the importance of maintaining adequate situational awareness in stressful search-and-rescue operations, and proper decision making when selecting a retrieval site.
Water in Fuel Felled Aerial Application Helicopter
Bell 206B, near Woodville, Texas, Sept. 24, 2015–Shortly after departure on an aerial application flight in daytime VMC, the engine lost power in a climbing right turn over pine trees. The pilot lowered the nose and avoided the tree line but had insufficient altitude to restore rotor rpm and enter a controlled autorotation. The helicopter collided with terrain and rolled onto its right side, sustaining significant damage to the fuselage, tail boom and rotor blades. The pilot was seriously injured.
Before departure, the helicopter had been fueled with 20 gallons of jet-A from a company support vehicle. Subsequent testing for water throughout the helicopter’s fuel system and in the support vehicle’s supply tank revealed significant water contamination. “Mostly...clear water with drops of fuel” was found in the engine fuel filter.