MIA97LA006

NTSB accident investigation · Cessna 150F · Lexington, TN · October 19, 1996

Accident · Serious injuriesLimited investigationFinal report
Date
October 19, 1996, 09:45 local (14:45 UTC)
Place
Lexington, TN
Injuries
2 serious
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N7102FCessna 150F
Weather
Visual (VMC) · Day
Status
Completed · report May 30, 1997
Report
Approved by Office Director
FAA report
19961019033189A
Case key
38169

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

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Probable cause

failure of the pilot to abort the takeoff after encountering excessive ground roll, and failure (or inability) of the pilot to obtain/maintain adequate airspeed, which resulted in an inadvertent stall. Factors relating to the accident were: restricted movement of the No. 4 cylinder exhaust valve, due to improper engine overhaul by the previous owner/mechanic, and failure of the current owner to perform maintenance after being advised by a pilot of excessive rpm drop during a carburetor heat check.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Loss of engine power(partial) - mech failure/malfTakeoff - initial climb
Engine assembly,valve,exhaust - movement restrictedFactor
Maintenance,overhaul,major - improperOther maintenance personnelFactor
Engine assembly,valve,exhaust - openFactor
Maintenance - inadequateCompany/operator managementFactor
Loss of control - in flightTakeoff - initial climb
Aborted takeoff - not performedPilot in commandCause
Airspeed - not obtained/maintainedPilot in commandCause
Stall - inadvertentPilot in commandCause
In flight collision with terrain/waterDescent - uncontrolled

Analysis

The pilot initially attempted to takeoff with a slight quartering tailwind, but he aborted the takeoff, then initiated a takeoff into the wind. Takeoff distance calculations showed that 1,315 feet would be required to clear a 50-foot obstacle. The airplane was observed to rotate about 4,300 feet down the 5,000 foot runway, climb to about 150 to 200 feet agl, roll left, then pitch nose down. The airplane impacted the ground nose and left wing low. Examination of the flight control systems revealed no evidence of a preimpact failure or malfunction. Examination of the engine revealed that the No. 4 cylinder exhaust valve was open. Dimensional measurements of the exhaust valve stem and the valve guide revealed that they had less then the minimum clearance as required by the overhaul manual. Review of the engine logbooks revealed that the engine was overhauled by an A & P mechanic in 1988. The overhaul manual indicated that after replacement of the exhaust valve guides, they were to be reamed to size. The engine had accumulated 443.96 hours since overhaul at the time of the accident. A pilot, who had flown the accident airplane on a previous flight, noted excessive rpm drop during the carburetor heat check. The airplane owner had been notified of the excessive rpm drop, but review of the maintenance records did not reflect that engine maintenance was performed.

Factual narrative

History of flight

On October 19, 1996, about 0945 central daylight time, a Cessna 150F, N7102F, registered to Floriplex, Inc., crashed shortly after takeoff from the Franklin Wilkins Airport, Lexington, Tennessee. Visual meteorological conditions prevailed at the time and no flight plan was filed for the 14 CFR Part 91 personal flight. The airplane was substantially damaged and the private-rated pilot and one passenger were seriously injured. The flight originated from the airport about 3 minutes earlier.

The pilot stated that he has no recollection of the accident and that he rented the airplane from the owner. He also stated that he did not perform weight and balance calculations before the flight. According to a witness, he advised the pilot not to utilize the sod runway because "the plane was a sick airplane and the runway was only 2,200 feet long." The pilot advised him he would use the paved runway and attempted to takeoff initially from runway 15. The witness observed the airplane rotate about 2,000 feet down the 5,000-foot runway then settle onto the runway and rotate again but again settled onto the runway. The pilot then aborted that takeoff and the witness further stated that he thought the pilot would abort the flight and return to the hangar, but the pilot then attempted to takeoff from runway 33. The airplane became airborne about 4,300 feet down the 5,000 foot runway and while in a nose-high attitude, climbed to about 150-200 feet above ground level then rolled to the left and pitched nose down. He lost sight of the airplane due to obstructions then heard the impact.

Personnel information

Information pertaining to the pilot is contained on page 2 of the NTSB Factual Report-Aviation. Additionally, according to his latest medical certificate, he weighed 265 pounds. The passenger stated that he weighed between 145 and 150 pounds at the time of the accident.

Aircraft information

Information pertaining to the airplane is contained on page 2 of the Factual Report-Aviation. Review of the engine logbook revealed that it was last overhauled on May 21, 1988, by an FAA certificated Airframe and Powerplant (A & P) mechanic who was also the previous registered owner of the airplane. Numerous attempts to contact the mechanic were unsuccessful. Review of the engine logbook pertaining to the overhaul revealed that in part, new exhaust valves and guides were installed for all four cylinders. The entry indicates that the mechanic followed the engine manufacturer overhaul manual. The engine had been operated for 443.96 hours since overhaul and 10.5 hours since the airplane was purchased by the current owner.

According to a pilot who flew with the accident pilot on August 8, 1996, in the accident airplane on two separate flights lasting a total of about 3 hours, there was no evidence of an engine malfunction on either flight.

A certified flight instructor who had flown the accident airplane on three separate flights, twice on August 11, and once on August 25, 1996, stated he thought the acceleration was "sluggish" during each takeoff roll but he did not calculate the takeoff distance for the flights. He also stated that before the first flight on August 11th, he had never flown a Cessna 150 airplane. The purpose of the first flight on August 11 was for aircraft familiarization and also to document discrepancies related to the airspeed indicator, suction gauge, and attitude indicator noted by the accident pilot who had flown the airplane 3 days earlier. The CFI noted that there was a noticeable rpm drop (400-500 rpm) when carburetor heat was applied at 1,700 rpm during the before takeoff checklist. He also noted that during the takeoff roll, the rpm gauge indicated 2,400 to 2,450. The next flight that day was with a student and again the rpm drop was excessive when the carburetor heat was checked during the before takeoff checklist. During the takeoff roll the rpm indicated the same and he noted excessive rpm drop when carburetor heat was applied in the downwind leg.

The third flight on the 25th was with a rated pilot and again during the carburetor heat check on the ground excessive rpm drop was observed. Before the takeoff with full power and the brakes applied, he noted that the static rpm was 2,400 to 2,450 rpm. The flight departed from the grass runway which has a slight upslope and he stated that the airplane barely cleared trees at the departure end of the runway. The flight returned and landed uneventfully; but then during a preflight of the airplane for another flight that day, water was noted in one of the fuel tanks. He canceled that flight and advised the owner of the airplane about the discrepancies relating to the airspeed indicator, suction gauge, attitude indicator, water in the fuel system, and the excessive rpm drop when carburetor heat was applied. He did not advise the owner about the incident in which the airplane barely cleared trees at the departure end of the grass runway.

Review of the engine logbook for the period when the CFI flew the airplane revealed only one entry dated August 11, 1996, in which the engine oil was changed.

Review of the airplane operating limitations indicates that the gross weight of the airplane is 1,600 pounds. Review of the airplane type certificate data sheet revealed that the minimum and maximum static rpm at full power with the installed propeller is 2,375 to 2,475 respectively. Additionally, the maximum rpm for the engine is 2,750 rpm. According to a Cessna Safety Supplement for the airplane, the maximum carburetor heat drop at full throttle is approximately 150 rpm.

Meteorological information

Visual meteorological conditions prevailed at the time of the accident. At 0940 CDT at the departure airport, a weather observation indicated in part that the wind was from 040 degrees at 3 knots.

Additional meteorological information may be obtained on page 4 of the Factual Report-Aviation.

Wreckage and impact information

The airplane was moved from the accident site before examination of it by the FAA and representatives of the airframe and engine manufacturer. The accident site was located adjacent to a high school building. Ground scars on grass adjacent to a small tree were noted and the flight path of the airplane was estimated to be on a magnetic heading of about 200 degrees. The airplane came to rest against another tree about 49 feet from the initial impact point.

Examination of the airplane revealed that all components necessary to sustain flight were attached to the airframe. According to the Cessna representative, chordwise crushing was noted on nearly the complete span of the leading edge of the left wing and on only the outer half of the right wing. Review of photographs taken by the representative revealed that the left and right wing tips were displaced up. Also, the aft inboard section of the left wing was displaced toward the fuselage. The fuselage aft of the trailing edge of the flaps was displaced to the left and the empennage forward of the horizontal stabilizer was displaced to the right. Aileron and rudder flight control cable continuity was confirmed from each control surface to the control column and rudder pedals respectively. Elevator flight control continuity was confirmed from the control surface to the damaged section in the cockpit area. The flap actuator was measured and the extension equated to 7 degrees. The left flap "up" cable was observed to be failed with signatures consistent with overload failure. The fuel selector handle was broken but the valve was determined to be "on." The aft portion of the left wing fuel tank exhibited evidence of hydraulic deformation and no fuel was observed. The right wing fuel tank was not was observed to be breached and a fuel sample was taken which revealed no evidence of con

Aircraft

Registration
N7102F
Reported as
Cessna 150F
Category
Airplane
Serial number
15063702
Airframe hours
4,527
Engine
Continental O-200-A, 100 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Registered owner
Floriplex, Inc.
Airworthiness certificate
Standard, Utility; Standard, Normal
Last inspection
Annual · October 19, 1995 · 20 hours before
Departed
M52
Airport
M52 · Franklin Wilkins, runway 33, 5,000 × 75 ft, asphalt

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
34
Certificate
Private
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 3, Valid Medical--no waivers/lim.
Seat
Right
Toxicology
Performed
Flight hours
809 total · 27 in this make and model · 700 as pilot in command · 14 in the last 90 days · 1 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
40° at 3 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
55 °F, dew point 36 °F
Altimeter
30.00 inHg
Observed at
M52, 1 nm away

FAA reports on this event · 1

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