N911BK

HISTORY OF FLIGHT

On December 10, 2012, about 2016 central standard time (CST), a Messerschmitt Bolkow-Blohm model BK 117-A3 helicopter, N911BK, impacted the ground near Compton, Illinois. The pilot, flight nurse, and flight paramedic were fatally injured, and the helicopter sustained substantial damage from impact forces. The emergency medical services (EMS) equipped helicopter was registered to Rockford Memorial Hospital, and operated by Air Methods Corporation under the provisions of 14 Code of Federal Regulations Part 135 as an on-demand air-taxi flight. Night visual meteorological conditions prevailed for the flight, which operated on a company visual flight rules flight plan. The flight originated from the Rockford Memorial Hospital Heliport (LL83), Rockford, Illinois, about 1958 and was en route to the Mendota Community Hospital Heliport (14IL), Mendota, Illinois, where it was to pick up a patient for transport back to the Rockford Memorial Hospital.

The helicopter was based at the Rockford Memorial Hospital (LL83), Rockford, Illinois. The purpose of the accident leg of the flight was to position the helicopter for a subsequent air medical inter-facility patient transport flight from the Mendota Community Hospital to the Rockford Memorial Hospital. The request was received by the Rockford Memorial Hospital Dispatch Center and the pilot was notified at 1927. During the initial call requesting the flight, the pilot confirmed acceptance of the flight. At 1959, the pilot reported to the dispatch center that he was departing from the helicopter's base at the hospital. He reported that he lifted off with one hour forty-five minutes of fuel and three persons on board and was en route to Mendota, Illinois. During the initial radio call the pilot stated that the risk category was alpha. At 2010, the pilot radioed that he was 12 minutes from Mendota. At 2016, the pilot contacted the dispatch center notifying that he was aborting the flight due to the weather conditions encountered. No further communications were received from the helicopter.

Flight track data for the helicopter showed that it departed LL83 at 1958 and proceeded south on a direct course toward 14IL. When the helicopter was about 13 miles from 14IL, it initiated a right turn. The initiation of the turn coincided with the time that the pilot reported that he was returning to base. The flight track then showed a slight descent before the end of the data. The last recorded position was about 0.75 miles east southeast of the main wreckage site.

PERSONNEL INFORMATION

The pilot held an airline transport pilot certificate with a helicopter rating. A type rating for Bell 206 helicopters was listed on the certificate. The certificate also listed private pilot privileges for single-engine land airplanes. He was issued a first-class airman medical certificate, with a restriction for corrective lenses, on July 17, 2012.

According to the operator's report, the pilot had accumulated 7,619 hours total flight experience with 446 hours in the same make and model helicopter as the accident helicopter. He had flown 27 hours in the preceding 90 days and 11 hours in the preceding 30 days. His most recent flight review was conducted on January 11, 2012. The flight review was conducted in a BK 117 Helicopter.

The pilot was assigned to a VFR only flight operations base. The training records indicated that during the January 11, 2012, flight review the pilot performed a limited review of instrument flight procedures. The instrument procedures listed on the training form consisted of recovery from instrument meteorological conditions, and an instrument landing system (ILS) instrument approach. Since the pilot was assigned to a VFR only operation, a full review of instrument procedures was not required.

According to operator duty time records, the pilot had started his shift about one hour prior to the start of the accident flight. He had been on-duty a total of 61.2 hours during the preceding five days and had accumulated 2:47 (h:mm) of flight time, including 1:49 of night flight, during that period. The duty time records showed that the pilot worked shifts of about 12 hours each day. With about 12 hours of time off between work shifts.

AIRCRAFT INFORMATION

The helicopter was a turbine-powered twin-engine medium utility–transport helicopter with a single main rotor system and an anti-torque tail rotor mounted on the rear of the helicopter. It was powered by two Lycoming LTS 101-650 B-1 engines bearing serial numbers LE45139EA and LE45306EA respectively. Each engine was rated to produce 592 shaft horsepower for short durations and 550 horsepower continuously. The helicopter was equipped with two doors on each side of the helicopter and a two-piece clam-shell door at the rear of the fuselage under the tail-boom. The accident helicopter was configured for patient transport. In addition to the two pilot stations, the rear of the helicopter had provision for a patient litter, two rearward facing seats, and a two position side facing bench seat.

The helicopter had accumulated 10,836 hours total flight time as of the date of the accident. Engine number one had accumulated 9,800 hours total time in service and engine number two had accumulated 10,518 hours total time in service. The most recent inspection was performed on November 1, 2012 under an Approved Airworthiness Inspection Program (AAIP).

METEOROLOGICAL INFORMATION

The pilot had WSI and Aviation Sentry Weather as computer based weather resources available to him before the flight, but neither system logs access, so there was no record or knowledge of the weather information obtained by the pilot before the flight.

The National Weather Service (NWS) Surface Analysis Chart for 2100 depicted a warm front stretching from northern Iowa northwestward into the northern Plains. A surface high pressure center with a pressure of 1021-hectopascals (hPa) was located in Oklahoma. The station models around the accident site depicted air temperatures in the mid 20's to low 30's Fahrenheit (F), with temperature-dew point spreads of 5° F or less, a west wind between 5 and 15 knots, cloudy skies, and light snow.

The area surrounding the accident site was documented utilizing official NWS Meteorological Aerodrome Reports (METARs) and Specials (SPECis).

Rochelle Municipal Airport (RPJ) was the closest official weather station to the accident site located about 2 miles south of Rochelle, Illinois, and had an Automated Weather Observing System (AWOS) whose reports were not supplemented by a human observer. RPJ was located 9 miles north of the accident site, at an elevation of 781 feet, and had a 1° westerly magnetic variation.

At 1955, the RPJ weather observation was, wind from 270° at 6 knots, 10 miles visibility, light snow, an overcast ceiling at 3,100 feet above ground level ( agl), temperature of -1° C, dew point temperature of -2° C, and an altimeter setting of 29.93 inches of mercury. Remarks: automated station with precipitation discriminator, temperature of -1.3° C, dew point temperature of -2.4° C.

At 2015, the RPJ weather observation was, wind from 290° at 8 knots, 7 miles visibility, light snow, an overcast ceiling at 3,300 feet agl, temperature of -1° C, dew point temperature of -2° C, and an altimeter setting of 29.94 inches of mercury. Remarks: automated station with precipitation discriminator, temperature of -1.5° C, dew point temperature of -2.3° C.

At 2035, the RPJ weather observation was, wind from 280° at 6 knots, 7 miles visibility, light snow, an overcast ceiling at 3,300 feet agl, temperature of -2° C, dew point temperature of -2° C, and an altimeter setting of 29.94 inches of mercury. Remarks: automated station with precipitation discriminator, temperature of -1.7° C, dew point temperature of -2.5° C.

At 2055, the RPJ weather observation was, wind from 280° at 9 knots, 7 miles visibility, light snow, scattered clouds at 1,200 feet agl, scattered clouds at 1,800 feet agl, an overcast ceiling at 3,300 feet agl, temperature of -2° C, dew point temperature of -3° C, and an altimeter setting of 29.94 inches of mercury. Remarks: automated station with precipitation discriminator, temperature of -1.8° C, dew point temperature of -2.8° C

Airmen's Meteorological Information (AIRMET) Zulu and Sierra were valid for the accident site at the accident time. They were issued at 1445 and forecasted moderate icing between the freezing level and 12,000 feet (with the freezing level between the surface and 4,000 feet), and IFR conditions with ceilings below 1,000 feet and visibility below 3 miles in precipitation and mist:

RFD was the closest site with a NWS Terminal Aerodrome Forecast (TAF). The TAF valid at the time of the accident was issued at 1720 and was valid for a 24-hour period beginning at 1800. The TAF expected wind from 270° at 6 knots, visibility greater than 6 miles, and a broken ceiling at 2,500 feet agl around the time of the accident.

The Area Forecast issued at 1345 forecasted a broken ceiling at 3,500 feet msl with tops at 7,000 feet. Until1500, widely scattered light snow showers were expected.

Weather radar imagery at 2017 cst near the accident site and aircraft's location indicated small droplets sizes, or a small amount of hydrometeors in the beam, hydrometeors that are spherical or near spherical in shape as they fall, and all the hydrometeors in the scan near the accident site had the same or very similar physical characteristics. One indicator, Zdr, was an indicator of the shape of the dominant hydrometeors. Negative Zdr values indicated a more vertical shape, positive values indicated a more horizontal shape, and values near zero indicated a near spherical hydrometeor shape. In between the aircraft's location at 2007 and 2017 cst there was a distinct change in the Zdr values, with two small horizontal bands of enhanced Zdr where the Zdr values were between 0.25 and 1.5 dB. The recorded Zdr ...