ERA20LA308

NTSB accident investigation · American AA 1 · Newnan, GA · September 5, 2020

Accident · No injuriesClass 3 · LimitedFinal report
Date
September 5, 2020, 18:50 local (22:50 UTC)
Place
Newnan, GA · In trees bordering airport property
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N6107LAmerican AA 1
Defining event
Approach-VFR go-around: Fuel related
Weather
Visual (VMC) · Dusk
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Eastern Region Aviation
Parties
FAA FSDO
FAA report
20200905016339A
Case key
101927

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 flight instructor’s inadequate preflight fuel planning, which resulted in an interruption of the fuel supply to the engine and a subsequent a total loss of engine power due.

Findings · 2

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.

Fluids: fuelAircraft › Fluids/misc hardware · Fluid levelAmerican AA-1: 3 casesAll aircraft: 1,695 casesProbable cause
Info processing/decision: decision making/judgmentPersonnel issues › Action/decision · Instructor/check pilotAmerican AA-1: 1 caseAll aircraft: 3,098 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

During the preflight inspection of the airplane, the flight instructor used the sight gauges inside the airplane to estimate that there was a total of approximately 10 to 11 gallons of fuel on board between the two wing fuel tanks. The flight instructor and the pilot receiving instruction departed and conducted maneuvers, simulated losses of engine power, and performed at least eight takeoffs and landings over the course of about 50 minutes. During a simulated loss of engine power in the airport traffic pattern, after descending to 300 ft above the ground, the pilot receiving instruction attempted to perform a go-around. The engine did not respond as expected and they performed a forced landing to a grassy area bordering the runway. During the landing attempt, the airplane impacted a taxiway marker and trees bordering the airport, resulting in substantial damage to the left wing and fuselage. The amount of fuel onboard at the time of the accident and its distribution was not determined; however, a postaccident test run of the engine revealed no evidence of any preimpact mechanical failures or malfunctions that would have precluded normal operation. During a postaccident interview, the flight instructor estimated that the airplane’s fuel consumption was about 6 gallons per hour (gph). Review of fuel consumption data from the engine and airframe manufacturer showed that the engine could be expected to consume between 6.5 and 7.3 gallons per hour at higher power settings, and that the fuel consumption could be as much as 9.5 gallons per hour when producing full power. These fuel consumption rates did not account for fuel consumed during taxi, run up, and takeoff. Given the quantity of fuel onboard at the time of departure, the duration of the flight, the likely fuel consumption rate of the engine, and that the engine was successfully test run after the accident, it is likely that the loss of engine power was the result of an interruption of fuel flow to the engine; however, whether the fuel supply was completely exhausted or only the fuel in one of the tanks was exhausted could not be determined based on the available information. Had the flight instructor elected to depart with additional fuel, it is likely that the accident would not have occurred.

Factual narrative

On September 5, 2020, about 1850 eastern daylight time, an American Aviation AA1, N6107L, was substantially damaged when it was involved in an accident at Newnan Coweta County Airport (CCO), Newnan, Georgia. The flight instructor and pilot receiving instruction were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight. According to the flight instructor, he used the sight gauges inside the airplane to estimate that there was approximately 10 to 11 gallons of fuel on board before the flight. During preflight inspection, they took fuel samples, and there were no indications of contamination or water in the fuel. This was the instructor’s third flight with the private pilot receiving instruction, who was also a possible buyer of the airplane. They were conducting various maneuvers and simulated loss of engine power procedures, and had conducted about 8 or 9 takeoffs and landings for a total flight time of about 50 minutes. Just before the accident, the pilot and the flight instructor were practicing a simulated loss of engine power from an altitude of about 800 ft while on the downwind leg of the traffic pattern for runway 32. After reducing the engine power to idle for the simulation, they descended to about 300 ft above ground level, after which the pilot applied full power to go around, but the engine did not respond and remained at low power. The flight instructor took control of the airplane and attempted to troubleshoot, but was unable to restore engine power. The airplane continued to descend, and the instructor attempted to make a forced landing in the grass adjacent to runway 32. The airplane touched down on the right side of runway 32, impacted a lighted taxiway sign box, veered sharply to the left, and subsequently impacted the trees bordering the west side of the airport property. The fuselage came to rest on an embankment between two trees that were impacted by the left and right wings. The impact nearly separated the left wing from the fuselage and the right outboard portion of wing was crushed. The airplane rested on the embankment at about a 60° nose-down position. The cockpit, fuselage, engine compartment, and propeller remained relatively intact. The quantity of fuel in the fuel tanks could not be determined given the position of the wreckage, but following recovery of the wreckage from the accident site, both fuel tanks were found absent of fuel. The condition of the fuel tanks was not documented, and whether there was any fuel spillage at the accident site before recovery of the airplane was not determined. Examination of the engine confirmed powertrain continuity through 720° of crankshaft rotation at the propeller hub. After confirming powertrain continuity, an engine run was accomplished. A portable fuel tank supplied fuel to the engine through the right fuel tank supply line; the fuel selector was not moved, and was in the same position as discovered at the accidentsite. After priming, the engine started on the second attempt and ran continuously at idle speed. All indications remained nominal and there was no anomalous behavior with the engine or any corresponding systems. Engine power was applied from idle to maximum power with no anomalous behavior from any of the systems. Examination of the wreckage and engine revealed no preimpact mechanical anomalies that would have precluded normal engine operation. The airplane was equipped with a Lycoming O-235-L2C engine driving a 2-blade Sensenich fixed pitch propeller. The airplane held 12 gallons of fuel in each wing tank cell for a total of 24 gallons, of which 22 gallons was usable. The fuel was managed by a fuel selector valve on the center console marked left, right, and off, and the fuel quantity was indicated by sight gauges located on the left and right side of the cockpit. The Lycoming engine operator’s manual for the O-235 series engine indicated that at performance cruise (75% rated power) at 2,500 rpm, the engine would consume 6.7 gallons per hour (gph) and at full power and 2,800 rpm, it would consume 9.5 gph. Section V of the airplane’s pilot operating handbook stated that performance information was derived from actual flight test and was corrected to standard atmospheric conditions. Actual performance varied based on atmosphere, engine and propeller condition, mixture leaning techniques, and other performance variables. In addition, fuel consumption was computed for level flight with the mixture leaned. At 2,500 feet and 85% rated power (2,600 rpm), the engine consumed 7.3 gph, and at 77% rated power (2,500 rpm), the engine consumed 6.5 gph. During a postaccident interview, the flight instructor stated that the airplane’s engine consumed about 6 gph.

Aircraft

Registration
N6107L
Reported as
American AA 1 (Undesignat)
Category
Airplane
Serial number
AA1-0307
Built
1969
Airframe hours
3,464
Engine
Lycoming O-235-L2C, 118 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Operator
Horton Steven K
Registered owner
Horton Steven K
Airworthiness certificate
Standard, Normal
Last inspection
Annual · June 17, 2020 · 15 hours before
Destination
Same as departure
Airport
CCO · Newnan Coweta County, runway 33, 5,500 × 100 ft, asphalt
Equipment
ADS-B

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 · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
61
Injuries
None
Certificate
Airline transport
Airplane ratings
Single-engine sea, Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 1
Seat
Right
Restraint
3-point
Flight hours
26,870 total · 35 in this make and model · 18,420 as pilot in command · 200 in the last 90 days · 25 in the last 30 days
Role
Pilot
Age
72
Injuries
None
Certificate
Private
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 3, With waivers/limitations
Last flight review
September 4, 2020
Seat
Left
Restraint
3-point
Flight hours
3,500 total · 5 in this make and model · 3,300 as pilot in command · 5 in the last 90 days · 5 in the last 30 days · 0 in the last 24 hours

Weather

Conditions
Visual (VMC) · Dusk
Wind
360° at 7 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
86 °F, dew point 57 °F
Altimeter
30.17 inHg
Observed at
CCO, 1 nm away

Docket · 7

The files NTSB released with the investigation on September 12, 2022, on NTSB’s docket system: statements, records, photos and specialists’ reports. 11.2 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.