ERA10FA503

NTSB accident investigation · Cessna 150F · Sweetwater, TN · September 26, 2010

Accident · FatalField investigationFinal report
Date
September 26, 2010, 10:59 local (14:59 UTC)
Place
Sweetwater, TN
Injuries
1 fatal
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N7915FCessna 150F
Defining event
Enroute: VFR encounter with IMC
Weather
Instrument (IMC) · Day
Status
Completed · report August 11, 2011
Report
Approved by Office Director
NTSB office
Eastern Region Aviation
Parties
Cessna Aircraft Company, FAA/FSDO, Continental Motors
FAA report
20100926049039A
Case key
77398

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

The pilot's inadequate preflight weather planning and improper decision to continue a visual flight rules flight into instrument meteorological conditions, which resulted in spatial disorientation and a loss of control.

Findings · 4

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Planning/preparation: weather planningPersonnel issues › Task performance · PilotCessna 150F: 2 casesAll aircraft: 156 casesProbable cause
Ceiling/visibility/precip: low ceilingEnvironmental issues › Conditions/weather/phenomena · Effect on operationCessna 150F: 1 caseAll aircraft: 190 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The private pilot did not possess an instrument rating and had not logged any actual instrument experience. During the 2 days prior to the accident flight, the pilot had completed two cross-country flights uneventfully and he was returning home on the accident flight. The pilot did not contact the flight service station for a weather briefing. Visual meteorological conditions prevailed at the departure airport; however, instrument meteorological conditions were present along the route of flight and near the destination airport. About 1 hour into the cross-country flight, the airplane impacted hilly terrain about 1,300 feet mean sea level (msl). Radar data indicated that 1 minute prior to the accident, the airplane began a right turn, followed by a descending left turn, with the last recorded target at 1,600 feet msl about 1/4 mile from the accident site. One witness stated that it was foggy in the area at the time of the accident. The recorded weather at a nearby airport, located at 1,031 feet msl, included an overcast ceiling at 600 feet. Examination of the wreckage did not reveal any preimpact mechanical malfunctions. If neither horizon or surface references exist, the attitude of an airplane must be determined by artificial means from the flight instruments. However, during periods of low visibility, the supporting senses sometimes conflict with what is seen, and when this happens, a pilot is particularly vulnerable to spatial disorientation.

Factual narrative

HISTORY OF FLIGHT On September 26, 2010, at 1059 eastern daylight time, a Cessna 150F, N7915F, owned and operated by a private individual, was substantially damaged during impact with trees and terrain, while maneuvering near Sweetwater, Tennessee. The certificated private pilot was killed. Instrument meteorological conditions prevailed and no flight plan was filed for the planned flight to Knoxville Downtown Island Airport (DKX), Knoxville, Tennessee. The personal flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. The flight originated from Cobb County Airport (RYY), Marietta, Georgia, about 0945. According to owner/operator, the airplane was based at DKX and the pilot was a friend who borrowed the airplane to visit family. On September 24, 2010, the pilot flew uneventfully from DKX to Columbus-Lowndes County Airport (UBS), Columbus, Mississippi. After the trip, the pilot telephoned the owner and reported that the airplane performed well. On September 25, 2010, the pilot flew uneventfully from UBS to RYY. The pilot was returning from RYY to DKX when the airplane impacted a hill located about 6 miles northwest of Monroe County Airport (MNV), Madisonville, Tennessee. Two witnesses in the area reported hearing an airplane "sputter" and then crash into a ridgeline. One witness stated that the airplane appeared to approach from the east. The other witness stated that the area was foggy and she did not see the impact. According to radar data provided by the Federal Aviation Administration (FAA), a target with a transponder code of 1200 was recorded traveling northeast from RYY. The target was indicating an altitude of 3,900 feet mean sea level (msl) at 1039, then 3,000 feet at 1044, where it remained until 1058. At that time, the target began a right turn, followed by a descending left turn. The last radar target was recorded at 1059:28, about 1/4 mile northwest of the accident site, with an associated altitude of 1,600 feet msl. PERSONNEL INFORMATION The pilot, age 64, held a private pilot certificate with a rating for airplane single-engine land. The pilot did not possess an instrument rating. His most recent FAA third-class medical certificate was issued on July 22, 2009. According to the pilot's logbook, he had accumulated a total flight experience of 329.6 hours; of which 24 hours were logged as simulated instrument conditions and none were logged as actual instrument conditions. None of the simulated instrument experience was logged within the 10-month period preceding the accident. The pilot had flown 5.6 hours during the 90-day period preceding the accident, not counting the recent flights to UBS and RYY, which had not been recorded in the logbook. AIRCRAFT INFORMATION The two-seat, high-wing, fixed-gear airplane, serial number 15064015, was manufactured in 1966. It was powered by a Continental Motors O-200, 100-horsepower engine, equipped with a McCauley fixed-pitch propeller. Review of the airplane'slogbooks revealed that its most recent annual inspection was completed on July 3, 2010. At that time, the airplane had accumulated 3,582.8 total hours of operation. The engine had also accumulated 3,582.8 total hours of operation since new, and 1,986.8 hours since overhaul. The airplane had flown about 13 hours since the most recent annual inspection. METEOROLOGICAL INFORMATION According to data from Lockheed Martin, the pilot contacted a flight service station on September 25, 2010, for the flight from UBS to RYY. During that telephone conversation, the pilot filed a visual flight rules flight plan. The weather briefer asked the pilot if he was familiar with the adverse weather conditions along the planned route of flight, and the pilot replied yes. There was no record of the pilot contacting a flight service station or data user access terminal for the accident flight the following day. The recorded 0947 weather at RYY was: wind calm; visibility 10 miles; scattered clouds at 700 feet; overcast ceiling at 4,800 feet, temperature 21 degrees Celsius (C); dew point 19 degrees C; altimeter 29.92 inches of mercury. The recorded 1056 weather at MNV, located at 1,031 feet msl, was: wind from 320 degrees at 4 knots; visibility 9 miles; overcast ceiling at 600 feet; temperature 17 degrees C; dew point 17 degrees C; altimeter 29.93 inches of mercury. WRECKAGE AND IMPACT INFORMATION The wreckage was located about 1,300 feet mean sea level (msl). All major components of the airplane were accounted for at the scene. No debris path was noted, except for two scarred trees, oriented from north to south. The airplane came to rest upright, left wing down, nose low, on a heading of approximately 060 degrees magnetic. The empennage remained intact with minor damage noted to the elevator and rudder. Both wings remained attached to the airframe. The left aileron was resting in an upward position, the right aileron was in a downward position, and the flaps were retracted. The left wing fuel tank was approximately three-fourths full of fuel. The fuel appeared bright, clear, and consistent with 100-low-lead aviation gasoline. The cockpit area was crushed. The throttle lever was found near the idle position and the mixture was in the rich position. The carburetor heat was off and the magneto switch was positioned to "Both." The airspeed indicator was positioned at 170 knots and the attitude indicator was tumbled. After the wreckage was recovered from the hill, aileron control continuity was confirmed from the cockpit controls to each wing root, where the cables had been cut by recovery personnel, and then to the left and right ailerons, respectively. Elevator, elevator trim, and rudder control cable continuity was confirmed from the cockpit controls to the forward empennage section, where the cables were cut by recovery personnel, and then to their respective control surfaces. A measurement of the elevator trim jackscrew revealed an approximate 5-degree tab up position.The engine remained attached to the airframe and the propeller remained attached to the engine. One propeller blade exhibited s-bending and chordwise scratches. The other propeller blade exhibited chordwise scratching and polishing. The propeller was rotated freely by hand. Camshaft, crankshaft, and valvetrain continuity was confirmed and thumb compression was attained on all cylinders. The top spark plugs were removed for inspection; their electrodes were intact and light gray in color. The carburetor was disassembled and examined. The examination revealed that the floats and needle valve remained intact. MEDICAL AND PATHOLOGICAL INFORMATION An autopsy was performed on the pilot on September 27, 2010, by the University of Tennessee Medical Center, University Pathologists, P.C., Knoxville, Tennessee. Toxicological testing was performed on the pilot by the FAA Bioaeronautical Science Research Laboratory, Oklahoma City, Oklahoma. Review of the toxicology report revealed: "Propranolol detected in Liver Propranolol detected in Blood." On the pilot's most recent application for an FAA third-class medical certificate, under "18. Medical History, h. High or low blood pressure," the pilot indicated "Yes, h. - slightly high B P." TESTS AND RESEARCH A handheld global positioning system (GPS) receiver was recovered in the wreckage and retained for further examination by the NTSB Vehicle Recorders Laboratory, Washington, DC. Data was successfully downloaded from the unit; however, the make and model GPS unit did not record time or altitude, only position track points. The track points depicted a northwest track from RYY toward Dalton Municipal Airport (DNN), Dalton, Georgia, then a northeast track toward DKX, consistent with the observed radar data. ADDITIONAL INFORMATION Review of FAA Advisory Circular 60-4A revealed: "The attitude of an aircraft is generally determined by reference to the natural horizon or other visual references with the surface, if neither horizon or surface references exist, the attitude of an aircraft must be determined by artificial means from the flight instruments. However, during periods of low visibility, the supporting senses sometimes conflict with what is seen, when this happens, a pilot is particularly vulnerable to disorientation. The degree of disorientation may vary considerably with individual pilots, Spatial disorientation to a pilot means simply the inability to tell which way is up."

Aircraft

Registration
N7915F
Reported as
Cessna 150F
Category
Airplane
Serial number
15064015
Airframe hours
3,583
Engine
Cont Motor O-200 SERIES, 100 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Doug Hair
Registered owner
Doug Hair
Airworthiness certificate
Standard, Normal
Last inspection
Annual · July 3, 2010 · 13 hours before
Departed
RYY · Marietta, GA
Destination
DKX · Knoxville, TN

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
64
Injuries
Fatal
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, With waivers/limitations
Last flight review
July 21, 2009
Seat
Left
Toxicology
Performed
Flight hours
330 total · 240 as pilot in command · 6 in the last 90 days · 1 in the last 30 days

Weather

Conditions
Instrument (IMC) · Day
Wind
320° at 4 knots
Visibility
9 statute miles
Lowest ceiling
600 ft overcast
Temperature
63 °F, dew point 63 °F
Altimeter
29.93 inHg
Observed at
MNV, 6 nm away

Docket · 15

The files NTSB released with the investigation on June 14, 2011, on NTSB’s docket system: statements, records, photos and specialists’ reports. 11.3 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.