History of Flight
On December 10, 2015, at 1903 Pacific standard time, a Bell 407 helicopter, registration N408FC, was destroyed when it impacted terrain during cruise flight near McFarland, California. The commercial pilot, flight paramedic, flight nurse, and patient sustained fatal injuries. The helicopter was registered to American Airborne EMS, Fresno, California, and operated by Rogers Helicopters, Inc., doing business as SkyLife, under 14 CFR Part 135 as call sign SkyLife 4. Night visual meteorological conditions prevailed, and a company VFR flight plan was filed. The flight originated from Porterville Municipal Airport (PVT) at 1849 with an intended destination of San Joaquin Community Hospital, Bakersfield, California.
The helicopter had been dispatched from Visalia Municipal Airport (VIS) to transfer a patient from PVT to Bakersfield. Data from a handheld GPS showed departure from VIS at about 1734, arrival at PVT at about 1756. The accident pilot spoke with a check pilot at about 1800, discussing weather concerns. The flight departed PVT at 1849:47. GPS data indicated a southerly course along State Highway 65, climbing to about 1,000 ft with groundspeeds between 125-141 mph. From 1855:58, the helicopter continued southerly, ascending to a maximum GPS altitude of 1,554 ft at 1902:43 with groundspeeds between 124-144 mph. Between 1903:08 and 1903:20, altitude decreased from 1,535 to 1,476 ft and groundspeed increased to 138 mph. At 1903:28, a left turn began while descending through 1,300 ft at 141 mph. The last recorded data points showed continued descent, with a calculated rate of descent of 2,210 ft per minute. At 1927, the dispatcher radioed the pilot without response. Wreckage was located by a sheriff's office helicopter at 2054; the pilot reported dense ground fog between 200-500 ft AGL and heavy rainfall.
Personnel Information
The pilot, age 49, held a commercial pilot certificate with rotorcraft helicopter and instrument ratings, and a flight instructor certificate. He held a second-class medical certificate dated April 8, 2015, with a requirement to wear corrective lenses. He was hired by Rogers Helicopters on August 15, 2012, and initially flew Bell 206 and MD530/MD500 helicopters for ferry and LIDAR work. On June 4, 2015, he was reassigned to the Bell 407 with a special training authorization for EMS. His logbook, from August 27, 2009, to December 10, 2015, showed 11,415.3 total flight hours, including 159.3 night hours (17.8 between August 2009 and accident date), 4 hours in actual instrument conditions, and 55.3 hours simulated instrument time. In the Bell 407, he had 48.8 total hours, 11.2 in the accident helicopter, including 15 night hours (2.3 in accident helicopter comprising 2 hours night training with 0.78 hours NVG training). In the 90 days before the accident, he flew 5.2 night hours, 0.3 in the accident helicopter 2 days prior. He had not flown a helicopter with advanced avionics before the accident helicopter. The pilot's wife reported he expressed concerns about not having NVG and had started but not completed company NVG training. A company pilot also reported the accident pilot expressed concern about flying near terrain at night without NVG.
Aircraft Information
The accident helicopter, serial number 53450, was configured for helicopter air ambulance (HAA) operations. The FAA type certificate required one flight crewmember and permitted day or night VFR operations. It was equipped with a Garmin G500H glass cockpit system installed in February 2013, including a GDU 620 display, GRS 77 AHRS, and GDC 74 air data computer. The helicopter also had analog airspeed and altimeter but no additional attitude reference instruments. It was configured for NVG use. The engine was a Rolls-Royce M250-C47B turboshaft, serial number CAE-847778, with maximum takeoff power 650 shp. The most recent annual inspection was June 1, 2015, at 9,017.5 airframe hours. The pilot primarily flew another company Bell 407, N101HF, which had analog instruments rather than the advanced avionics of the accident helicopter.
Meteorological Information
At 1854, weather at PVT (elevation 443 ft, 21 nm north of accident site): wind 040° at 5 knots, visibility ≥10 statute miles, light rain, overcast ceiling 3,300 ft, temperature/dew point 12°C, altimeter 29.91 inHg. At BFL (14 nm south): wind 280° at 4 knots, visibility ≥10 miles, overcast ceiling 6,000 ft, temperature 14°C, dew point 11°C, altimeter 29.91 inHg. No weather stations were along the route. The nearest WSR-88D radar (47 nm northwest) showed light to moderate reflectivity east, northeast, north, and northwest of the accident site at 1902. An NWS area forecast discussion at 1516 noted areas of marginal VFR/IFR with mountain obscurations spreading south. AIRMET advisories for instrument conditions, mountain obscuration, and moderate turbulence were in effect. Postaccident, NWS meteorologists indicated conditions were conducive to fog; ground fog in the area is commonly shallow, 150-300 ft AGL.
Wreckage and Impact Information
The helicopter impacted open, sparsely populated, unlit, hilly terrain about 9 miles east of McFarland. A debris path about 465 ft long oriented at 037° magnetic contained all major components. The first identified point of contact (FIPC) was a ground scar consistent with a main rotor blade strike. Two additional similar scars were found at about 12 and 21 ft beyond the FIPC. Adjacent to the 21-ft scar was an impact crater about 12 inches deep, 29-54 inches wide, and 5 ft long, containing portions of a landing skid, antenna, and fuselage panel. The left skid was found 77 ft from the FIPC, left door lower portion at 126 ft, right skid at 213 ft, inboard yellow main rotor blade at 226 ft. The main wreckage was at 260 ft and tailboom at 337 ft. The fuselage came to rest upright, oriented at 330° magnetic. The main rotor head remained attached; three of four blades were attached. The forward fuselage was torn open, crushed, and twisted. The tailboom separated aft of the fuselage attach point. The vertical stabilizer separated and was adjacent to the fuselage. Examination at Plain Parts revealed no pre-impact anomalies. The forward fuel cell contained 20-24 gallons of fuel (removed before recovery); the aft fuel cell was ruptured with no fuel noted. Main rotor blades showed ground impact marks. Continuity was established for flight controls; separations were consistent with impact damage. No evidence of foreign object or wildlife strike was found. The engine showed no pre-impact anomalies; the ECU recorded no faults before the sequence, with one line of data including an NR drop below 92%.
Tests and Research
Engine examination at Rolls-Royce found no operational failure or malfunction. The lower chip detector had a small metal sliver; fuel and oil filters were debris-free. N1 and N2 rotated freely. The bleed valve housing was fractured consistent with impact. Compressor blades were bent opposite rotation direction; dirt was found throughout the gas path. Turbine disassembly showed no operational failure. Servo examination at Bell Helicopter found no pre-accident deficiencies; each servo passed functional checks. Avionics examination of the GRS 77H AHRS and GDU 620 display was performed. The AHRS assert log recorded an entry at 19:03:40, indicating a software-initiated reset due to an abrupt excessive change in body roll angular rate exceeding 16 degrees/second. The velocities at that moment were North 53.7 knots, East 100.7 knots, Down 34.4 knots, with a calculated descent rate of about 3,486 ft per minute. The air data computer recorded true airspeed of 113.3 knots. Functional tests of the AHRS and display were unremarkable. The GDU 620 had no recorded logs on the accident day.
Organizational Information
Rogers Helicopters started in 1962, with EMS operations beginning in 1991. At the time of the accident, it was headquartered in Fresno, California, operating 3 airplanes and 38 helicopters, employing about 55 pilots. For EMS, it operated two Bell 407s, a Bell 430, and a Beech King Air. SkyLife was a partnership with American Ambulance, which provided medical crew and equipment; Rogers provided pilot and aircraft. The SkyLife SOP manual stated the pilot-in-command is the final authority for safe operations. Rogers' Part 135 Operations Manual outlined weather minimums: for nighttime cross-country VFR, ceiling 1,000 ft AGL and 3 miles visibility. The company's Flight and Ground Risk Analysis Program used a risk assessment worksheet; the accident pilot's worksheet showed a risk factor of 7 (below the decline factor of 17), noting night flight, scene call, new pilot, and rested status. The pilot had completed 0.78 hours of NVG training; initial NVG qualification required 7 hours ground and 5 hours flight.