CHI08FA128

The pilot’s failure to maintain clearance from trees along the top of a ridgeline due to inadequate preflight planning, insufficient altitude, and the lack of a helicopter terrain awareness and warning system. Member Sumwalt did not approve this brief and probable cause. Member Sumwalt filed a dissenting statement that can be found in the public docket for this accident.

After transporting a patient to a local hospital and refueling at La Crosse Municipal Airport (LSE), the emergency medical services (EMS) helicopter departed LSE (elevation 656 feet mean sea level [msl]) about 2234 central daylight time (all times in this brief are central daylight time) on a return flight to its base heliport. Dark night visual meteorological conditions (VMC) prevailed at LSE. A ramp services employee at LSE who had observed the helicopter lift off and proceed east-southeast observed “moderate” rain and “fair” visibility at the time of takeoff. Witnesses located southeast of the airport reported hearing the helicopter in flight about the time of the accident, and one witness reported hearing a loud crashing sound. A search was initiated shortly after the crash but was hampered by the terrain and fog that had formed overnight. A search located the helicopter the following morning; the helicopter had impacted trees along a sparsely populated ridgeline about 5 miles southeast of LSE. The elevation of the ridgeline was approximately 1,164 feet msl, with 50- to 60-foot-tall trees in the area initially struck by the helicopter. Distribution of the wreckage was consistent with the helicopter impacting the trees in a nearly level flight attitude under controlled flight. Examination of the helicopter’s engines revealed inlet debris, rotational scoring, and centrifugal turbine blade overload failures consistent with the engines being operated at a moderate to high power level (on both engines) at the time of impact. Nonvolatile memory downloaded from the digital engine control units (DECUs) indicated that both engines were in “flight mode” at the time of impact. Although the left engine main selector switch was observed in the “idle” position after the accident, the lack of anomalies related to the switch and the corresponding DECU in flight mode are consistent with the switch having been moved as a result of impact. No preimpact mechanical malfunctions of the helicopter were found. The reported weather conditions at LSE about 2253 included VMC: calm winds, 8 miles visibility in light rain, few clouds at 1,400 feet above ground level (agl) [2,056 feet msl], overcast clouds at 5,000 feet agl (5,656 feet msl), temperature 10 degrees C, dew point 8 degrees C, and altimeter 29.70 inches of mercury. The preflight weather briefing obtained by the pilot about 1 hour before departure indicated VMC along the route of flight at the time of the briefing but forecasted deteriorating conditions later in the evening after about 2200, including possible instrument meteorological conditions (IMC). Search and rescue personnel reported fog and mist along the ridgeline overnight during the search operations. Additionally, an EMS pilot for another operator reported that when he departed LSE about 2 hours before the accident flight, fog was beginning to form on the west side of the Mississippi River and in the bluffs east of his flight route. He subsequently returned to LSE and declined at least one additional flight that evening due to deteriorating weather conditions. Because of the variability in weather conditions on the night of the accident, the investigation could not determine if the pilot encountered IMC at the time of the accident. The pilot was transferred to the accident operator as a result of the accident operator’s acquisition of his previous employer about 3 months before the accident. The accident pilot was initially qualified as visual flight rules (VFR)-only. An instrument proficiency check was not completed in conjunction with initial training. As a result, the accident pilot was limited to VFR-only operations at the time of the accident. (The accident pilot was current for instrument flight rules [IFR] at his previous place of employment.) During preflight planning, the pilot should have identified any obstacles along the route of flight, including the tree-covered ridgeline. Company records indicated that the pilot had completed one prior flight to LSE within the previous 16-month period, which was about 2 months before the accident. To assist pilots, maximum elevation figures (MEF) are noted on sectional charts and are derived from such features as terrain, trees, and towers. An MEF is specified for each latitude/longitude quadrangle on the chart. Operation at or above the applicable MEF will ensure terrain and obstacle clearance. The MEF for the La Crosse area is 2,200 feet msl. In addition to the MEF, sectional charts depict terrain elevation and specific obstacle height information. If the accident pilot had observed the MEF of 2,200 feet msl, or the terrain elevation/obstacle height information, it would have provided clearance of the tree covered ridgeline. The elevation of the ridge in the vicinity of the tree strikes was approximately 1,164 feet msl. With the 50- to 60-foot-tall trees, the elevation of the treetops was about 1,224 feet msl, providing a margin of approximately 831 feet to the level of the reported “few clouds” and 4,431 feet to the overcast layer of clouds. According to Air Methods Corporation, the accident pilot performed a formal flight risk assessment before the flight. Further, the flight was being tracked by a company flight-following program and received flight dispatch services before the start of the flight. According to the Air Methods General Operating Manual, the pilot’s risk assessment was to be recorded in the pilot’s daily flight log. However, the pilot’s daily flight log was destroyed during the crash. The pilot entered a risk assessment of “A” (normal operations) into the flight dispatch computer system before the flight. While the weather in the LSE area was marginal at the time of the accident, it was above the minimums required by Federal Aviation Administration (FAA) regulations and the operator’s procedures. There were no identified weather risks that would have warranted classifying the flight in the risk assessment category “B” (caution). A radar altimeter was installed on the helicopter and, according to Air Methods, was normally set to 500 feet for night flight. On December 21, 2007, the National Transportation Safety Board (NTSB) issued Safety Recommendations A-07-111 and -112, asking the FAA, respectively, to require helicopter EMS (HEMS) operators to install radar altimeters in all helicopters used in HEMS night operations and ensure that the minimum equipment lists for helicopters used in HEMS operations require that radar altimeters be operable during flights conducted at night. On March 10, 2008, the FAA stated that it agreed with the intent of these recommendations and was considering rulemaking to require all 14 Code of Federal Regulations Part 135 HEMS operators conducting night HEMS operations to have an operable radar altimeter installed in the helicopter. On August 17, 2009, the FAA indicated that it revised FAA Order 8900.1, “Flight Standards Information Management System,” to provide standards and procedures for inspectors to evaluate flat light or whiteout training programs for all helicopter operators. The FAA also stated that an in-progress notice of proposed rulemaking (NPRM) for air ambulance and commercial helicopter operations would address the safety intent of these recommendations. On March 12, 2010, the NTSB stated that, although it agrees that increased training for pilots may be of benefit in avoiding accidents where radar altimeters are needed, issuing guidance and standards for such training is not responsive to these recommendations. The NTSB further indicated that it is pleased to learn that the planned NPRM will include language proposing the recommended requirements for radar altimeters. Pending the issuance of a final rule requiring (1) the installation of radar altimeters in all helicopters used in HEMS night operations and (2) the inclusion of a requirement on the minimum equipment list

HISTORY OF FLIGHT On May 10, 2008, about 2237 central daylight time, a Eurocopter Deutschland GmbH EC 135 T2+ air medical configured helicopter, N135UW, operated by Air Methods Corporation, was destroyed during an in-flight collision with trees and terrain near La Crosse, Wisconsin. The flight was conducted in accordance with 14 Code of Federal Regulations Part 91. A flight plan had not been filed with the Federal Aviation Administration (FAA). Night visual meteorological conditions prevailed in the vicinity of the accident site. The pilot, physician and flight nurse sustained fatal injuries. The flight departed the La Crosse Municipal Airport (LSE), La Crosse, Wisconsin, at 2234. The intended destination was the University of Wisconsin Hospital heliport (WS27) in Madison, Wisconsin. The helicopter was equipped with global positioning system (GPS) tracking equipment that provided departure, arrival and en route position information to the operator’s Operations Control Center (OCC). Flight progress was automatically updated approximately every three minutes and tracked by the operator’s OCC. According to the GPS flight-following data, the flight initially departed WS27 about 2038 en route to Prairie du Chien Memorial Hospital, Prairie du Chien, Wisconsin. The flight arrived there about 2113 and picked up a patient. The flight subsequently departed about 2131 and proceeded to Gunderson-Lutheran Hospital in La Crosse, arriving about 2154. After dropping off the patient, the crew departed about 2209 and repositioned the helicopter to LSE for refueling. The flight departed LSE at 2234 with the intention of returning to WS27. No further position updates were received from the accident helicopter. The line service technician who fueled the helicopter noted that when it departed, it lifted off vertically and proceeded east-southeast. Regarding the weather conditions, he added that the visibility was “fair”, with a “low ceiling” and “moderate rain” at the time. A witness located approximately 4.2 miles east-southeast of LSE reported hearing a helicopter fly over about 2230. He was in a restaurant parking lot getting into his car at the time. He noted that it sounded like a Medlink helicopter. He reported that it seemed to be "traveling at a high rate of speed, and was flying low." He recalled thinking that it was not going to clear the bluffs. A second witness contacted the La Crosse County Sheriff's Office about 2240 and stated that he heard a helicopter flying overhead, when the sound of the engine disappeared followed by a loud crashing sound. Local authorities initiated a search at that time. At 2304, the helicopter operator notified local authorities that the helicopter was missing. The helicopter wreckage was subsequently located about 0826 the next morning. PERSONNEL INFORMATION The pilot, age 39, held a Commercial Pilot certificate with single and multi-engine land airplane, helicopter, instrument airplane, and instrument helicopter ratings. He was issued a Second-Class Airman Medical certificate on July 14, 2007, with a limitation for corrective lenses. The pilot also held a Mechanic certificate with airframe and powerplant ratings. The pilot's logbook was not obtained by the NTSB. The operator reported the accident pilot’s flight experience as 4,003 hours total flight time, with 2,741 hours in rotorcraft, and 121 hours in EC135 helicopters. The pilot’s night flight time was 545 hours and instrument flight time was 216 hours. Within the 90-day period prior to the accident, the pilot had flown 49 hours in EC135 helicopters. Duty time records indicated that in the 30-day period prior to the accident, the pilot had flown 17.0 hours. Of that total, 5.8 hours were at night. The operator initially noted that the pilot had accumulated 2.7 hours of actual instrument flight time during the previous 12 months. However, they subsequently advised that the accident pilot had accumulated 2.5 hours of instrument flight time between July 2005 and March 2008. During the 12-month period preceding the accident, the pilot acquired a total of 0.4 hours actual instrument flight time; all of which was during a single flight on May 17, 2007. The accident pilot was hired by CJ Systems on March 1, 2001, as a mechanic. CJ Systems operated the University of Wisconsin Med Flight program at that time. During his tenure as a mechanic, he reportedly also acted as a pilot on maintenance test flights. He transferred to a full-time pilot position on December 1, 2005. Air Methods Corporation purchased CJ Systems in March 2008, and the Madison-based pilots were transferred to Air Methods. At the time of the transition to Air Methods, the pilots were provided training under the Air Methods operating certificate. Training records indicated that the accident pilot completed basic indoctrination for Air Methods and EC 135 helicopter specific ground training in January 2008. He completed further training related to aeronautical knowledge and EC 135 P2 helicopter specific knowledge between February 2008 and April 2008. On March 10th and 11th, 2008, the accident pilot completed 3.5 hours flight training in an EC 135 T2+ helicopter. According to company records, he passed Part 135 Competency and Line Checks on March 11, 2008. An instrument proficiency check was not completed at that time. As a result, the accident pilot was limited to visual flight rules (VFR) operations under the Air Methods certificate at the time of the accident. There were two flights on record to the La Crosse area for the accident pilot between January 1, 2007, and the day of the accident. On March 7, 2008, the pilot had transported a patient from Prairie du Chien Memorial Hospital to Gunderson Lutheran Hospital in La Crosse. The second was the flight on the evening of the accident. AIRCRAFT INFORMATION The accident helicopter was a 2007 Eurocopter Deutschland GmbH EC 135 T2+ helicopter, serial number 0535. It was powered by two Turbomeca Arrius 2B2 turboshaft engines. The helicopter was certificated under FAA type certificate H88EU and issued a standard airworthiness certificate on March 14, 2007. It had accumulated 456.7 hours total flight time as of the day of the accident. Both engines had accumulated the same amount of time as the airframe. In the 30-day period prior to the accident, the helicopter accumulated 39.8 hours. The helicopter was maintained under an FAA Approved Aircraft Inspection Program (AAIP). A routine airworthiness check was completed on the day of the accident with no discrepancies noted. According to the operator’s records, the most recent inspection procedure was a 400-Hour inspection completed on March 17, 2008, at 386.1 hours airframe total time. A 12-Month inspection and a 100-Hour Supplementary inspection were completed on February 26, 2008, at 375.7 hours total airframe time. Altimeter and pitot static system inspections were also completed at that time. During those inspections, a crack was observed in the upper and lower skins of one of the main rotor blades. The blade was replaced at that time. The maintenance records noted that on April 16, 2008, the helicopter fell off a tug damaging the landing light and the electrical cannon plug. The damage was repaired and the aircraft returned to service. With the exception of an inoperative landing light, there were no further discrepancies recorded in the aircraft maintenance records within the 90-day period prior to the accident. The records noted that landing light bulb had been replaced prior to the day of the accident. At the time of the accident, the helicopter was equipped with a radar altimeter. It was not equipped, nor was it required to be equipped, with a terrain awareness warning system (TAWS). METEOROLOGICAL INFORMATION The National Weather Service (NWS) Surface Analysis Chart valid at 2200 depicted a low pressure system to the south of the accident