NTSB Factual Report

HISTORY OF FLIGHT

On October 11, 1997, about 2051 eastern daylight time, a Piper PA-28-180, N15331, registered to a private owner, operating as a 14 CFR Part 91 personal flight, crashed in the Tennessee River, about 1 mile west of the Downtown Island Airport, Knoxville, Tennessee. Visual meteorological conditions prevailed and no flight plan was filed. The airplane sank and was destroyed. The private-pilot and two passengers were fatally injured. The flight was originating at the time.

The airplane and its occupants had arrived in Knoxville earlier in the day to attend a University of Tennessee football game. According to airport personnel, the three occupants arrived back at the airport after the game, about 2030, and after the control tower had closed. The control tower was staffed 2 hours before and after the University of Tennessee football games. The pilot had line service personnel put 24 gallons of fuel in the airplane, and according to the line service manager, this "filled the tanks."

The airplane was seen by several witnesses climbing in a westerly direction, about 200 feet above the ground (AGL), in a nose-high attitude, wings rocking, and lights on. Witnesses said the airplane turned, went into a nose-low attitude and impacted the water. Several witnesses said the airplane's engine was "revving" and sounded "loud," before impacting the water. One witness said the engine sounded like it was at "full power."

Two witnesses, a married couple, were walking near the river, when they saw the airplane come from the airport and fly in a westerly direction, down river, on the left side or south bank of the river. According to statements the witnesses gave to the FAA, the male witness said, "...the aircraft was real low, just above the bridge. It started to climb to try to clear the bridge. The nose went up and the aircraft flipped over and nose dived into the water." The female witness said she heard the airplane take off, and saw the same things that her husband saw. She said, "...it barely cleared the bridge...when the aircraft cleared the bridge, it was over the center lanes of the road. It turned to the left and went straight down into the water...sank and was totally immersed within five minutes of impact...the plane backfired after the left turn before descent into the water."

A third witness, on his boat going up river just past the west end of the runway said, "...when the aircraft took off, the wings started to wobble, tipping back and forth." He further said his mother heard the airplane, and saw the airplane's lights going into the water.

The accident occurred during the hours of darkness about 35 degrees, 57 minutes north, and 083 degrees, 52 minutes west.

PERSONNEL INFORMATION

Information on the pilot is contained in this report on page 3, under First Pilot Information.

METEOROLOGICAL INFORMATION

Visual meteorological conditions prevailed at the time of the accident. Meteorological information is contained in this report on page 3, under Weather Information. The winds were reported to be calm at the time of the accident.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy was performed on the pilot, on October 13, 1997, at the University of Tennessee, Medical Center, Knoxville, Tennessee, by Dr. Sandra K. Elkins. According to the autopsy report the pilot, "...died as a result of multiple injuries sustained in the crash. At autopsy he [pilot] was found to have severe coronary artery disease."

Toxicological tests were conducted at the Federal Aviation Administration, Research Laboratory, Oklahoma City, Oklahoma, and revealed, "no ethanol." The drug screen revealed, "...6.100 (ug/ml, ug/g) Salicylate detected in blood." Salicylate is found in aspirin.

WRECKAGE INFORMATION

The airplane impacted in about 20 feet of water into the Lake Loudoun section of the Tennessee River, east of the South Knoxville Bridge. The accident site was located about 3 miles east of the city of Knoxville, at an elevation of about 800 feet above sea level. The airplane was retrieved from the water and transported to a hangar at the airport, where the airframe and engine were examined.

Examination of the left wing revealed that it had separated from the fuselage at the wing root. The entire length of the leading edge was crushed rearward to the main spar. The wing tip had fractured on the top side about 4 inches aft of the leading edge. The aileron was found attached to the hinges and the balance weights were found in place. The aileron control cables were found connected at the bell crank, but had separated near the wing root. The flap was found attached to the hinges, and the flap control rod had separated from the flap control arm. The position of the flap at impact could not be determined. The fuel tank had ruptured and no fuel was found. The main landing gear displayed impact damage.

Examination of the right wing revealed that about 6 feet of the inboard right wing had separated from the fuselage at the wing root. Eight feet of the outboard section of the right wing was never recovered from the water, including the aileron and balance weight. The leading edge of the wing was separated and torn aft of the main spar. About 12 inches of the flap was recovered, and the flap had separated from the hinges. The aileron cables were found separated near the wing root. Tension overload fractures were observed on the cables. The fuel tank had ruptured and no fuel was observed in the tank. The main landing gear was found bent rearward about 45 degrees. The faring was not with the landing gear and was not recovered from the lake.

Examination of the fuselage revealed that the cabin roof was peeled rearward, exposing the cockpit. Both sides of the fuselage had separated at the baggage area. The rear baggage door was still attached to the hinges, and the door was found in the locked position. The instrument panel displayed extensive impact damage which destroyed the instruments and radios. The cabin door was in one piece, but had been torn from the frame. All of the cockpit windows were broken from their frames. Both front seats and the rear right seat were found separated from the their seat tracks. The left rear seat was found still attached to the floor. Control cable continuity was established from the wing root to the "T" bar assembly, and to the empennage.

The tail cone revealed that it was wrinkled starting at the baggage door rearward to the aft bulkhead. The stabilator was still attached, and did not display any damage. The stabilator trim tab jack screw measured 1 1/4 inches and seven threads were showing, which equated to about 2 degrees nose up. The stabilator control cables were found still attached, and continuity was established to the "T" bar assembly. The vertical stabilizer was still attached to the tail cone. The dorsal fin and the lower leading edge of the vertical stabilizer were found crushed rearward and to the right. The rudder was still attached to the stabilizer and did not display any damage. The rudder cables were found attached, and rudder cable continuity was established from the rudder, to the rudder bell crank, forward to the rudder pedals.

The engine remained partially attached to the airframe. The propeller had remained attached to the crankshaft flange. The left and right exhaust pipes were compressed and bent rearward. The exhaust muffler was found compressed. The carburetor had separated from the oil sump. The fuel line fitting had separated from the engine driven fuel pump.

TEST AND RESEARCH

The engine was removed from the airframe and examined at a hangar at the Downtown Airport. The crankshaft rotated freely by hand. Compression was observed to all cylinders by use of a thumb compression check. Valve train continuity was established to all the cylinders. All the accessory gears rotated and engine continuity was established. Examination of the engine did not reveal any discrepancies.

The spark plugs were removed and water was observed coming from the cylinders when the No. 2 and No. 3 bottom plugs were removed. The spark plugs displayed a gray color and some corrosion. The electrodes did not display any discrepancies. Examination of the carburetor revealed that the composite floats operated. The float retention pin was in place and the needle valve operated. There was no fuel found in the bowl. The throttle was found in the full open position at the carburetor, and the mixture arm was found at the 3/4 rich position. Both magnetos rotated freely by hand. No spark was observed. The ignition wires were found frayed. The vacuum pump rotated freely by hand. The vacuum pump was disassembled and no damage was observed to the internal parts.

Observation of the propeller blades revealed that they were both bent rearward. One of the blades displayed an "S" shaped bend. Chordwise scratches and gouges were found on the chambered surface, from the blade tip inboard about 16 inches. The other blade was found bent rearward about 45 degrees. The trailing edge of the blade displayed abrasions from the tip of the blade inboard to the bent area of the blade.

ADDITIONAL INFORMATION

The aircraft wreckage was released to Mr. Jerry W. Marshall, Line Service Manager, Campbell Aero Inc., on October 13, 1997. There was no representative of the owner available at the time the wreckage was released.

NTSB Probable Cause

failure of the pilot to maintain control of the airplane, while climbing after takeoff, which resulted in an uncontrolled descent and impact with the water.