FTW03FA086

The 3,300-hour commercial pilot lost control of the airplane while circling an area of disturbed dirt along the path of a buried pipeline during an aerial observation flight (pipeline patrol). The operator reported that pipeline patrolling is normally performed from an altitude of 400 to 500 feet above the ground. The range of the airplane, when all tanks are full of fuel is 6 hours; however, the company procedures are to not exceed 4 hours between refueling stops. The operator reported that the pipeline being patrolled at the time of the accident was aligned on a heading of 50-60 degrees. The prevailing winds at the time of the accident were reported from 030 degrees at 15 knots, gusting to 19 knots. The hand-held GPS on-board the airplane provided the track of the airplane to impact with the ground. No anomalies were found with the airframe or engine that could have prevented normal flight operation.

History of flight

On January 21, 2003, at 1230 central standard time, a Cessna 152 single-engine airplane, N47257, was destroyed upon collision with trees and terrain following a loss of control while maneuvering at low altitude near Norman, Oklahoma. The airplane was owned by a private individual and was being operated by Texas Aerial Inspections, of Roanoke, Texas, under Title 14 Code of Federal Regulations Part 91. The instrument rated commercial pilot, sole occupant of the airplane, was fatally injured. Visual meteorological conditions prevailed throughout the area for the aerial observation flight (pipeline patrol) for which a flight plan was not filed. The flight made a scheduled refueling stop at the Chickasha Municipal Airport at 1044, and the flight was continued at 1105.

The operator reported that the flight departed from their home base at the Northwest Regional Airport (52F), near Roanoke, Texas, at 0630 on the morning of the accident. The operator added that the range of the airplane, when all tanks are full of fuel is 6 hours; however, the company policy is not to exceed 4 hours between refueling stops. The operator added that the pipeline being patrolled at the time of the accident was aligned on a heading of 50-60 degrees. The pipeline, which is identified as "Line 8-1300," was owned by the Oklahoma Natural Gas (OGT) and operated by ONEOK. Pipeline patrolling is normally conducted from an altitude of 400 to 500 feet AGL.

A pile of freshly disturbed red dirt was visible from the accident site, approximately 300 feet northeast the resting place of the airplane. The operator stated that freshly disturbed dirt is one of the reportable conditions that are normally noted and documented by pipeline patrol pilots. Data from the pilot's hand-held GPS revealed that the pilot was flying on the right side of the pipeline being observed. It also confirmed that the pilot performed a left turn over the pipeline and pile of disturbed red dirt. After one turn, he continued to observe the area by making another left turn. When he made the second left turn, the GPS showed a drastic reduction of ground speed followed by the end of the track (flight).

Eyewitnesses reported to news media reporters that the airplane circled to the left over the area of the accident site at low altitude. One witness reported that the airplane circled twice and "then dove into the trees." Another one stated that the airplane appeared to be flying "erratic as if no one was at the controls."

Data provided by the Federal Aviation Administration (FAA) confirmed that the pilot was not provided a weather briefing for the accident flight. Additionally, they confirmed that, due to the low altitude of the flight, no radar data was available on the flight from air traffic control (ATC).

Personnel information

The 61-year old commercial pilot had been employed by Texas Aerial Inspections for over 2 years. The pilot was a retired medical officer in the U.S Army. According to FAA records, the commercial pilot certificate was issued on November 8, 1968.

His last physical examination was completed on April 18, 2002, and an FAA Class II medical certificate was issued. In the application for his last physical certificate, the pilot reported having accumulated a total of 3,300 flight hours. The pilot held a commercial license with ASEL and AMEL. He also held a commercial license in helicopters and an instrument rating in both airplanes and helicopters. The pilot completed his last BFR on August 20, 2002.

The pilot was carrying a Sony digital camera in the airplane to document any anomalies noted while patrolling the pipeline. The badly damaged camera, which appeared to have a 3.5-inch floppy disk loaded, was found to be empty.

Aircraft information

The airplane was manufactured by Cessna Aircraft in 1979, and was issued serial number 152-83200. The airplane was equipped with the extended fuel range configuration, which consisted of 19.5-gallon fuel cells in each wing. On September 24,1997, the aircraft was modified to a present configuration under an FAA field approval, to modify the airplane for long range patrolling. The airplane was fitted with an additional 14.2-gallon fuel tank, which was installed in the baggage compartment, to extend the range of the airplane. The airplane operated in the experimental category for a year after the completion of the modifications. The airplane was later issued a restricted category certificate on September 24, 1997. Its last airworthiness certificate was issued on April 21, 1999. The aircraft remained in the tricycle gear configuration. The gross weight of the airplane remained at 1,670 pounds.

The last 100-hour inspection was completed on Dec 15, 2002, at 10,478 tachometer hours. The last annual inspection was completed on March 28, 2002 at 9,461 tachometer hours.

The airplane was equipped with a 4-cylinder Lycoming O-320-E2D engine, serial number L-25151-27A, rated at 150 horsepower. The engine was driving a 2-bladed McCauley fixed pitch propeller, model number MTM 7656, serial number E-11908.

Data obtained from the Garmin 196 GPS revealed that the airplane landed at the Chickasha Municipal Airport (CHK) for fuel at 1044, and departed at 1105 local. That morning, the airplane was fueled with 43.98 gallons of 100LL at CHK. The CHK airport is located 37 nautical miles west-southwest of the accident site. The aircraft had a supplemental type certificate (STC) for automotive fuel; however, the airplane was operating with 100LL aviation fuel at the time of the accident.

Meteorological information

At 1230 local, the recorded weather at the University of Oklahoma Westheimer Airport (OUN), near Morman, Oklahoma, located approximately 13.6 nautical miles west (101 degrees) from the accident site, was reporting clear skies, visibility 10 statute miles, winds from 030 degrees at 15 knots gusting to 19 knots, temperature 5 degrees Celsius, dew point 01 degree Celsius, altimeter setting 30.07 inches of Mercury. There was no convective activity reported within 100-mile radius of the accident site.

Wreckage and impact information

The wreckage of the airplane came to rest behind an electronic repair shop located at 15207 Cedar Lane, in Norman, Oklahoma. The airplane impacted trees and terrain on a measured heading of 050 degrees in an area covered with an assortment of scrub-oak trees commonly referred to as "blackjack oak." The collision with the trees knocked down several large branches from 3 matured trees, and knocked down 2 small trees.

The engine and the forward portion of the cockpit were found canted in a 40-degree nose down attitude. The bottom of the engine and one of the propeller blades were partly buried in a shallow crater. The engine mounts were damaged and fracture; however, the engine remained attached to the airframe.

The outer portion of the left wing was found separated from the wing. Portions of the wing were found near the base of the trees. The right wing remained its integrity despite several tree strikes on the leading edge.

The tail section of the airplane was severed from the airframe behind the pilot's seat. The entire tail assembly was twisted to the right of centerline and stayed in one piece. Both wing struts remained attached to their respective mounting points. The actuator for the wing flaps was found fully extended to the full flap position (30 degrees). The elevator trim tab was found in the neutral position.

Flight control continuity was established to all flight control surfaces. The right control cable for the rudder assembly was found separated approximately 8 inches forward of the attachment point. The fracture appeared to be overload; however, the cable strands had a rusty exterior appearance. All of the airframe components were found located within 20 feet of the resting