ANC98FA048

The noninstrument rated private pilot was issued adverse condition warnings and urgent pilot reports for severe turbulence. His route of flight took him up channeled, mountainous terrain requiring a climb to a minimum of 9,000 feet msl. Winds aloft were forecast to be between 28 and 41 knots. Surface winds were forecast to be in a downslope direction at 25 knots gusting to 50 knots from channeled terrain. Cessna 172 performance charts for the 180 horsepower engine indicate a maximum climb rate available of 405 feet per minute at 8,000 feet pressure altitude. Ceilings of 8,500 feet were reported on the west side of the mountains. The pilot radioed that he was going to try to get on top through a hole. The airplane was located on the west side of a peak, in deep snow, at 8,600 feet msl, about 40 hours after the departure. The Emergency Locator Transmitter signal was masked by terrain and wreckage. Both occupants were lightly dressed, and appeared to have survived the impact. The pilot was described by acquaintances as inexperienced and prone to taking chances with the airplane.

History of flight

On May 15, 1998, about 0915 Alaska daylight time, a Cessna 172M airplane, N9212H, was destroyed when it impacted mountainous terrain near the 8,600 feet msl level of the Radcliffe Glacier, about 38 miles east of Palmer, Alaska, at position 61 degrees, 21 minutes North latitude, 147 degrees, 52 minutes West longitude. The private pilot and the sole passenger sustained fatal injuries. The flight was conducted under 14 CFR Part 91, as a personal flight from Big Lake, Alaska, to Petersburg, Alaska. Visual meteorological conditions prevailed at Palmer, Alaska, at the time of the accident. Weather at the accident site is unknown.

A direct route of flight from Big Lake to the location of the wreckage would have taken the airplane over the Knik Glacier. This glacier constitutes continually rising terrain from Palmer, to the crest of the Chugach Mountain Range. The mountains are extremely rugged, and covered by glaciers and a large ice field at the higher elevations. The ice field area where the airplane came to rest is surrounded by peaks extending to 10,610 feet msl. The general direction of flight is eastward, and required the airplane climb from sea level to a minimum of 9,000 feet msl to clear the passes.

The airplane was reported overdue by a friend in Petersburg, Alaska, at 1100 on May 16. The airplane was located about 2300 on May 16, by an Alaska Air National Guard C-130 airplane.

Injuries to persons

Both occupants were confirmed to be deceased about 2300 on May 16. Severe injuries were not described by the two National Guard pararescuemen (PJs) who reached the site. The PJs described both occupants located outside, and below the airplane by 10 and 20 feet respectively.

Footprints were visible in the snow surrounding the airplane fuselage and the two occupants prior to the arrival of the PJs.

The female occupant was dressed in long pants and a sweater. The male was dressed in long pants and a medium weight jacket. Neither were wearing gloves. The male appeared to be wearing a hat. The National Guard mission report comments included, "It appeared both died of hypothermia." Other handwritten mission notes stated, "guy had injuries."

Damage to aircraft

The airplane sustained substantial damage, and has not been recovered.

Personnel information

The pilot held a private certificate for single engine land airplanes. He did not hold an instrument rating. His third class medical certificate was valid, with no restrictions. At the time of his last FAA medical examination he stated that he had accumulated 288 hours of flight time. He received his private pilot certificate on March 15, 1988.

The passenger was not a licensed pilot, but reportedly had soloed as a student. No FAA records of pilot experience of the passenger were received.

Interviews obtained by the Alaska State Troopers, and the Alaska National Guard, included the following statements from acquaintances and friends of the pilot: "The aircraft was fully equipped with nav gear and radio equipment, of which the pilot did not know how to operate any of it for the most part other than the radio." A friend's wife stated that her husband "didn't fly with the pilot because he wasn't an experienced pilot and took too many chances." This friend himself said that "the pilot was very inexperienced as a pilot and didn't think twice about taking chances with the aircraft."

Aircraft information

The pilot purchased the airplane in 1997.

The airplane was a Cessna 172M, modified by Supplemental Type Certificate with a Lycoming O-360-A1A engine, serial number L-23074-36A. The engine was rated to produce 180 horsepower at sea level at 2,700 propeller rpm. The airplane had a Sensinich model 76EM8S14-0-56 fixed pitch propeller, serial number 26581K. The propeller was repitched from 60 inches (cruise propeller) to 56 inches (climb propeller) prior to purchase by the pilot.

The Cessna 172Q operator's handbook, provides a rate of climb chart for Cessna 172 airplanes with an O-360 engine. This chart indicates that at 8,000 feet pressure altitude, an outside air temperature of 0 degrees C, a gross weight of 2,550 pounds, and a 76 inch long propeller pitched to 58 inches, that a climb rate of 405 feet per minute is available. This chart does not account for any additional climb rate available with a climb propeller.

The last weight and balance form for the airplane revealed an empty weight of 1,552 pounds. Full fuel of 48 gallons weighs 288 pounds. The Cessna 172Q fuel consumption chart indicates 1.4 gallons (8.4 pounds) consumed for taxi and 3.6 gallons (21.6 pounds) consumed to 8,000 feet. The pilot weighed 238 pounds according to his third class medical. The passenger weighed 128 pounds according to her driver's license. Total weight estimated at the time of the accident, excluding any personal items or cargo, is 2,176 pounds.

Meteorological information

Visual meteorological conditions prevailed at Big Lake (150 feet msl), and Palmer (248 feet msl) at the time of departure. The weather conditions at the accident site are unknown. Flight precautions for severe turbulence and mountain obscurations were in effect in the area forecast for the time of the accident.

The area forecast called for strong low level winds to intensify, and for surface winds out of passes and channeled terrain from the east and southeast of 25 knots gusting to 50 knots. All passes were forecast to be turbulent.

The weather reported at Palmer at 0853 was, scattered clouds at 7,000 feet, broken clouds at 8,500 feet, winds 130 degrees magnetic at 25 knots gusting to 32 knots. Visibility was reported as 7 miles with blowing dust in all quadrants.

The weather reported at Whittier at 0854 was, ceilings overcast at 7,000 feet, winds 080 degrees magnetic at 10 knots.

Communications

The last radio contact was at 0847 on May 15 with the FAA Kenai Flight Service Station, when the pilot requested current weather at Valdez. He was told that Valdez ceilings were 10,000 feet msl. The FSS specialist then stated, "we do have some urgent pilot reports of moderate to severe turbulence in the Anchorage Bowl area." The pilot was also advised of adverse conditions of turbulence, low level wind shear, mountain obscuration, icing, and isolated IFR.

The pilot stated to the FSS specialist at 0847 that, "...I'm heading down Knik Arm to look to see if I can go over the top. It looks good from here. If I see a hole I'm going to file a flight plan. Probably be 20-25 minutes. Otherwise we are going to have to take an alternate route."

No flight plan was filed.

Wreckage and impact information

The National Guard rescue mission notes state that the airplane came to rest at the 8,600 feet msl level on the western side of the western most peak of Radcliffe Glacier. A review of photographs taken by the Air National Guard helicopter crew who confirmed the fatalities indicated the airplane came to rest on a magnetic heading about 330 degrees. The wide pass in which the airplane was located is oriented generally east-west (070/250 degrees magnetic).

After the wreckage was located on May 16, and the two occupants were confirmed to be fatalities, three attempts were made by the NTSB and Alaska State Troopers to reach the site, extract the occupants, and examine the wreckage. The first two attempts, on May 19 and May 23, were abandoned due to weather at the accident site. On June 3, the NTSB IIC and a team of five other climbers reached the geographic location of the crash site. Large amounts of accumulated snow and avalanches had buried the airplane. Several hours of probing the crash site using avalanche rescue techniques failed to locate the wreckage.

The NTSB IIC conducted an overflight of the area on August 14, and observed large amounts of new snow, and extensive, new avalanche fields along the entire mountain slope where the airplane wr