History of Flight
On August 7, 2012, about 1645 Alaska daylight time, a McDonnell Douglas MD600N helicopter, registration N737TV, sustained substantial damage while landing on a remote helipad near Pogo Mine, 38 miles Northeast of Delta Junction, Alaska. The helicopter was operated by Aurora Aviation Services, Inc., as a 14 CFR Part 135 visual flight rules (VFR) on-demand charter flight. The certificated airline transport pilot was fatally injured. Visual meteorological conditions prevailed, and company flight following was in effect. The flight had departed from the Pogo Mine.
The helicopter had been based at Pogo Mine since May 2012, supporting exploratory gold mining operations by transporting personnel and equipment to remote drilling sites. Remote helipads were constructed at numerous drilling sites.
The helipad at Rig 3 was located about 1 mile southeast of the Pogo Mine runway, in steep, heavily forested terrain at an elevation of about 2,700 feet MSL. The helipad was constructed of logs interlaced and nailed together, approximately 16 feet wide by 21 feet long. The deck consisted of logs placed only at the forward and aft sections, with open spaces between.
On the accident day, the pilot had flown several missions to multiple helipads and conducted sling load operations. He was returning to the Rig 3 helipad to transport personnel back to the mine.
Witness Statements
A witness waiting at the helipad reported radioing the pilot for a pickup. He was kneeling beside the helipad when the helicopter touched down. The pilot turned his head to signal boarding when the helicopter pitched up and back, striking trees at the edge of the helipad. The helicopter rolled down the hill and came to rest on its left side. The engine was still running when the witness arrived.
Another witness working nearby heard the helicopter land, followed by a loud screeching noise and impact. After the accident, he noticed a log on the rear left side of the helipad displaced upward, with the attaching spike pulled out and the log displaced aft.
A third witness, about 500 feet northwest, heard the helicopter land, then a crash and debris flying. He saw a log from the rear portion of the helipad decking pulled from the structure and damaged. He also reported that on previous occasions, he had observed the pilot land forward on the helipad, allowing the tail of the landing gear skids to fall into the open area of the decking. The pilot would then reposition the helicopter so the skid tails rested on the four rear logs.
Medical and Pathological Information
A post mortem examination conducted on August 9, 2012, attributed the pilot's cause of death to blunt force traumatic injuries. Toxicology tests performed by the FAA Civil Aeromedical Institute on September 28, 2012, were negative for alcohol and drugs.
Wreckage and Impact Information
On August 8, NTSB investigators, FAA inspectors, and a company representative examined the wreckage. The helicopter was configured for left-seat flight control operation. All major components were at the main wreckage site, in steep, heavily forested terrain at about 2,700 feet MSL. The main debris path was on a 200-degree magnetic heading, downhill.
Scattered debris included broken Plexiglass and personal effects. The fuselage lay on its left side with the nose southeast. The cockpit was severely damaged with extensive deformation; all windscreens and overhead transparencies were shattered or missing. The aft cabin was slightly bent and buckled inward along the roof.
The right fore and aft landing gear struts fractured at the foot assemblies; the right skid was found left and aft of the main wreckage. The left forward strut fractured at the foot assembly, while the aft strut remained attached; the left skid fractured just aft of the front foot assembly and was uphill.
The NOTAR tail boom assembly severed just aft of the attach points and came to rest upright with its aft portion pointing toward the fuselage.
The main rotor blades (six all-metal) showed damage consistent with sudden stoppage from multiple ground and tree strikes while under power. No evidence of preimpact mechanical anomalies was found.
Personnel and Aircraft Information
The 64-year-old pilot held an airline transport pilot certificate with rotorcraft-helicopter rating and a type rating for Eurocopter/MBB BO-105. His total aeronautical experience was about 19,500 hours, with 306 hours in the accident helicopter make and model. He had completed all required training, including a Part 135 VFR competency check ride on May 12, 2012.
The helicopter was a 1997 McDonnell Douglas 600N with a Rolls Royce M250-C47M engine, having about 9,730 flight hours at the time of the accident. The most recent annual inspection was completed on April 1, 2012, and a 100-hour inspection on July 13, 2012, about 90 hours before the accident. The aft landing gear skids were fitted with Supplemental Type Certificate "Bear Paws" for soft or uneven terrain. No mechanical discrepancies were noted in the maintenance logs.
Meteorological Information
The closest weather reporting facility, Allen Army Airfield (41 miles southwest), reported at 1653: wind from 310 degrees at 13 knots gusting to 21 knots, visibility 10 statute miles, scattered clouds at 7,000 and 20,000 feet, temperature 65°F, dew point 7°F, altimeter 29.84 inHg.
Tests and Research
The wreckage was recovered and examined on September 5, 2012, with representatives from MD Helicopters, The Boeing Company, and Rolls-Royce Corporation. No preaccident airframe or engine anomalies were noted.
The pilot's Garmin GPSMAP 496 portable GPS was sent to the NTSB Vehicle Recorders Division. An electrical engineer extracted flight data including time, latitude, longitude, and GPS altitude; groundspeed and course were derived. A flight track map and tabular data are available in the public docket.