Aviation Accident Summaries

Aviation Accident Summary ANC07FA082

Arctic Village, AK, USA

Aircraft #1

N5660F

Maule M-5-180C

Analysis

The airline transport pilot and passenger departed a remote gravel site to scout the area near their hunting camp for sheep. The pilot told his son that they would return in about 30 minutes. Several days later, the pilot's son flagged down a passing airplane, and reported the missing airplane. Searchers located the airplane wreckage, about 4,000 feet elevation, on a steep slope in a canyon 3-4 miles from the hunting camp. The airplane impacted terrain on a steep scree slope, surrounded by high terrain, coming to rest about 200 feet upslope from the bottom of a steep ravine. The airplane wreckage was consumed by fire, but the basic structures remained, and all the major flight control components were present. The airplane impacted the slope at a steep, nose down attitude, coming to rest with the tail down slope, and against a rock outcrop on the right side. The left wing structure had rotated over the top of the fuselage, bending the rudder top to the right, and coming to rest on top of the right wing, consistent with the airplane spinning at impact. The propeller blades had extreme torsional twisting and bending, and chord-wise scratches indicating the production of power at the time of the impact. Given the steep, rising terrain, and the impact signatures on the airplane, it is probable the pilot elected to fly up the valley. In the process, he allowed the airspeed to decay, and stalled the airplane while maneuvering to avoid the rising terrain Due to the remote, hazardous location, the accident airplane was not recovered.

Factual Information

HISTORY OF FLIGHT On August 13, 2007, about 1615 Alaska daylight time, a tailwheel-equipped Maule M-5-180C airplane, N5660F, was destroyed by impact with terrain and a postcrash fire, following an in-flight loss of control and descent, about 36 miles north of Arctic Village, Alaska. The airplane was being operated by the pilot as a visual flight rules (VFR) personal local flight under Title 14, CFR Part 91, when the accident occurred. The airline transport certificated pilot and sole passenger received fatal injuries. Visual meteorological conditions prevailed, and no flight plan was filed. The airplane departed a remote gravel airstrip about 1600. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on August 21, a friend of the pilot said the pilot departed Gustavus, Alaska, on August 9, for Fairbanks, Alaska. He said the pilot was accompanied by a mutual friend, and the pilot's son. He said that they arrived on the afternoon of August 11, at a remote gravel airstrip north of Arctic Village, in the Brooks mountain range to hunt sheep . He said that the pilot's son told him that after two days of hunting, and not seeing any sheep, the pilot and passenger decided to scout the area with the airplane, stating that they would return in about 30 minutes. According to search officials, on August 13, the pilot's son flagged down a passing airplane, and reported his father's missing airplane. Searchers located the airplane wreckage, about 4,000 feet elevation, on a steep slope in a canyon 3-4 miles from the hunting camp. INJURIES TO PERSONS The pilot and sole passenger received fatal injuries. DAMAGE TO AIRCRAFT The airplane was destroyed by impact with terrain and postcrash fire. PERSONNEL INFORMATION According to FAA records, the pilot held an airline transport certificate, and had about 12,800 hours of flying experience. He was issued an FAA second class medical certificate on August 14, 2006. No personal flight logbooks were discovered for examination. AIRCRAFT INFORMATION The airplane was a 2006 model year, single-engine, fixed gear, tailwheel-equipped, Maule M-5-180C airplane. According to logbook entries, the airplane had accumulated 1,141 service hours. An annual inspection was completed in June, 2007. METEOROLOGICAL INFORMATION The nearest automatic weather reporting station is 36 miles south of the accident site at Arctic village. Automated observations two hours either side of the suspected accident time indicated good VFR conditions, with visibility 10 miles, and ceilings above 7,500 feet. According to the pilot's son, weather was good at the time of the airplane's departure. COMMUNICATIONS There were no known communications with the accident airplane. WRECKAGE AND IMPACT INFORMATION The onsite investigation by the IIC commenced on August 17. Initial attempts to reach the site failed, and the wreckage was viewed from a distance. On September 25, the wreckage was reached by the U.S. Army and Alaska State Troopers. Detailed photographs were provided to the IIC. The airplane impacted terrain on a steep scree slope, about 4,000 feet elevation in a wash about 2 miles above their campsite on Cane Creek, 36 miles north of Arctic Village. The site is surrounded by high terrain, and the airplane came to rest about 200 feet upslope from the bottom of a steep ravine. The airplane wreckage was consumed by fire, but the basic structures remained, and all the major flight control components were present. The airplane impacted the scree slope at a steep angle, coming to rest with the tail down slope, and against a rock outcrop on the right side. The left wing structure had rotated over the top of the fuselage, bending the rudder top to the right, and coming to rest on top of the right wing. The propeller blades had extreme torsional twisting and bending, and chord-wise scratches. Given the steep, raising terrain, and crash signatures on the airplane, it is probable the pilot elected to fly up the valley, toward rising terrain. In the process, he allowed the airspeed to decay, and stalled the airplane while maneuvering to avoid the rising terrain. MEDICAL AND PATHOLOGICAL INFORMATION An autopsy was performed on the pilot under the authority of the State of Alaska, Office of the State Medical Examiner, 4500 S. Boniface Parkway, Anchorage. The cause and manner of death of the pilot was determined to be multiple blunt force impact injuries due to an airplane crash. Tissue samples were sent to the FAA Aeronautical Center, P. O. Box 25082, Oklahoma City, Oklahoma, for toxicological analysis. Ethanol was detected in the blood, muscle, and brain, and N-Propenol was detected in the muscle. The quantities were consistent with postmortem production. An examination of FAA medical records revealed no significant medical history. ADDITIONAL INFORMATION Due to the remote location, the accident airplane was not recovered. No pieces or parts of the airplane were taken or retained by the NTSB.

Probable Cause and Findings

The pilot's failure to maintain sufficient airspeed to avoid a stall/spin while maneuvering.

 

Source: NTSB Aviation Accident Database

Get all the details on your iPhone or iPad with:

Aviation Accidents App

In-Depth Access to Aviation Accident Reports