NTSB Factual Report

HISTORY OF FLIGHT

On April 22, 1994, at 1445 eastern daylight time, a Bell 412 helicopter, N70AM, owned and operated by Air Methods Corporation of Denver, Colorado, collided with mountainous terrain during an instrument approach to Mercer County/Bluefield Airport Bluefield, West Virginia. All four occupants aboard the aircraft, the pilot, the co-pilot, and two flight nurses, received fatal injuries. The helicopter was destroyed. The flight originated in Winston Salem, North Carolina, at 1347 hours and was arriving at its destination to pick up a patient. Instrument meteorological conditions prevailed and an instrument flight plan was filed. The flight was operated under 14 CFR Part 91.

The pilot, co-pilot, and two flight nurses departed North Carolina Baptist Hospital to pick up a patient at the airport in Bluefield, West Virginia. The pilot received air traffic control services from a radar controller at the Indianapolis Air Route Traffic Control Center (ARTCC), and he requested vectors to ILS runway 23. The last transmission between the pilot and the controller was for the flight to maintain seven thousand feet until established on approach, and to fly heading two four zero. The flight was also cleared for the instrument landing system (ILS) approach to runway 23 at Mercer County, an uncontrolled airport. The pilot was instructed to contact the specialist at the Bluefield Flight Service Station (FSS) and reportedly made "normal" transmissions, with no indication of a problem. The helicopter impacted a mountain located 7 1/2 miles from the departure end of runway 23 at the 3400 foot level.

There were several witnesses who heard the helicopter overfly their homes, but could not see it due to the fog. One of the witnesses reported that, "I could not see anything then I heard this low noise I thought maybe it was going to land." Another witness stated that the helicopter was flying parallel with the mountain. "...It sounded like it was very low. The fog was below the tree line on the mountain....I said to myself you better get it up if you plan to clear the mountain. Then I heard a tree break then an explosion."

The accident occurred at daylight, about 37 degrees 18 minutes North latitude and 81 degrees 12 minutes West longitude.

PILOT INFORMATION

The pilot, age 45 years, held an airline transport pilot (ATP) certificate for helicopter operations. At the time of the accident, company records indicate that he had accumulated approximately 4094 total flying hours, of which 969 were in the Bell 412. He was issued a first class medical certificate with no limitations on December 16, 1993. In accordance with 14 CFR Part 135 requirements, he completed his last proficiency check on February 14, 1994 and he received his last recurrent training on February 1, 1994.

The co-pilot, age 32 years, held a commercial pilot certificate for helicopter operations, and a private pilot certificate with single engine land rating for airplane. At the time of the accident, company records indicate that he accumulated approximately 1412 total flying hours, of which 712 were in the Bell 412. He was issued a first class medical certificate with no limitations on April 12, 1993. In accordance with 14 CFR Part 135 requirements, he completed his last proficiency check on December 21, 1993, which included a check of instrument proficiency.

AIRCRAFT INFORMATION

The 1989 year model Bell 412/SP, serial no 33206, was equipped with two Pratt & Whitney PT6T-3B engines, serial nos. CPP 63179 and CPP 63180 respectively. The aircraft had over 2086 hours including 10 hours since the last annual inspection on April 19, 1994.

METEOROLOGICAL CONDITIONS

The 1450 hour surface weather observation for Bluefield Flight Service Station, about 7 miles east of the accident site was as follows:

"Sky condition, 500 feet overcast; visibility, 2 miles in fog and drizzle; temperature, 44 degrees (F); dew point, 44 degrees (F); wind condition, 010 degrees at 5 knots; and altimeter, 30.10 inches."

WRECKAGE AND IMPACT INFORMATION

The main wreckage lay inverted in a 25 foot diameter crater approximately 150 yards from the top of East River Mountain at the 3600 foot level. The wreckage was tied to a tree to avoid it from rolling down the 30-40 degree downslope. It was oriented on a magnetic heading of 335 degrees and strew a distance of about 200 feet. The initial impact point (IIP) was with trees at the 3400 foot level. At the IIP, paint chips, glass and plexiglass were found that matched the plexiglass from the helicopter.

A four foot section of the right skid tube forward section with a section of the front cross tube outboard saddle separated. The rotor head, main rotor blade mast, main transmission and associated flight control sump case separated and were located about 54 feet from the main wreckage. A one foot section of the main drive shaft with the data plate separated and was located about 33 feet from the main wreckage. The left and right horizontal stabilizer separated. A two foot section of the aft tail boom, 42 degree gearbox, vertical fin and 90 degree gearbox, and inboard portion of the output shaft separated and were located about 150 feet from the main wreckage. A two foot section of the tail rotor drive input shaft to the 42 degree gear box separated.

The tail rotor and hub with a section of the output shaft and crosshead assembly separated.

Control continuity of the drive train was confirmed by rotating the rotor in the direction of rotation. The engine to transmission drive shaft gears teeth, and the drive shaft to the 90 degree gearbox sheared. Control continuity of the tail rotor drive shaft and the drive shaft to the 90 degree gearbox was confirmed.

The cyclic control separated from the pilot's cyclic control stick at the base. The pilot's collective pitch control separated at the joint between the number one and two engines.

The wreckage was transported to Summitt Helicopters in Roanoke, Virginia. The engine was examined and there was no evidence of any mechanical malfunction that would have precluded operation.

MEDICAL AND PATHOLOGICAL INFORMATION

An examination was done by Dr William Massello III, Office of the Chief Medical Examiner in Roanoke, Virginia, on April 24, 1994. Toxicological tests did not detect alcohol, drugs, or carbon monoxide.

TESTS AND RESEARCH

The navigation instruments for the pilot and co-pilot including the VOR/localizer receiver and marker beacon receiver were sent to Allied Signal in Olathe, Kansas for examination. The examination included retrieving the frequencies and codes from non-volatile memory. Both VOR/localizers for the pilot and co-pilot were tuned to the localizer frequency of 109.5, with 110.0 for the Bluefield Vortac on the standby mode. The marker beacon sensitivity in the LO sense mode was within specifications. The sensitivity in the HI sense mode was 300 microvolts. The specification according to Allied Signal is for 200 microvolts. There was a BHT label on the case of the unit which indicated that the HI sensitivity was set to 300 microvolts. The test could not reveal the position of the marker beacon switch due to impact damage.

ADDITIONAL INFORMATION

Wreckage Release: The aircraft wreckage was released to Marshall B. Dean of the USAIG insurance company, the owner's insurance representative on October 15, 1994.

NTSB Probable Cause

THE PILOT'S FAILURE TO INTERCEPT THE FINAL APPROACH COURSE, AND HIS IMPROPER EXECUTION OF THE INSTRUMENT APPROACH PROCEDURE. FACTORS WHICH CONTRIBUTED TO THE ACCIDENT WERE: THE WEATHER CONDITIONS, AND THE FAILURE OF THE AIR TRAFFIC CONTROLLER TO ADEQUATELY VECTOR THE FLIGHTCREW TO INTERCEPT THE FINAL APPROACH COURSE AT THE APPROACH GATE, AS SPECIFIED IN THE ATC HANDBOOK.