WPR13LA251

NTSB accident investigation · American AA-1 · Truckee, CA · May 23, 2013

Accident · Serious injuriesLimited investigationFinal report
Date
May 23, 2013, 12:10 local (19:10 UTC)
Place
Truckee, CA
Injuries
1 serious
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N5909LAmerican AA-1
Defining event
Initial climb: Loss of engine power (total)
Weather
Visual (VMC) · Day
Status
Completed · report May 16, 2016
Report
Approved by Office Director
NTSB office
Western Pacific Region
Parties
Federal Aviation Administration
FAA report
20130523009589A
Case key
87038

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

The pilot's failure to lean the fuel mixture during takeoff in high-density altitude conditions, which resulted in a loss of engine power.

Findings · 3

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 · Incorrect use/operationAmerican AA-1: 3 casesAll aircraft: 1,695 casesProbable cause
Use of equip/info: use of policy/procedurePersonnel issues › Task performance · PilotAmerican AA-1: 1 caseAll aircraft: 191 casesProbable cause
Temp/humidity/pressure: high density altitudeEnvironmental issues › Conditions/weather/phenomena · Effect on operationAmerican AA-1: 2 casesAll aircraft: 278 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 was conducting a ferry flight for the airplane's owner. The pilot reported that, before takeoff, he leaned the fuel mixture for taxi but that, on takeoff, the mixture was full rich. During the initial climb, the engine lost power; the pilot stated that he did not remember anything after the loss of power occurred. The airplane subsequently collided with trees about 8 miles east of the airport, which is at an elevation of 5,901 ft and surrounded by mountainous terrain. Postaccident examination of the airframe and engine revealed no mechanical anomalies that would have precluded normal operation. According to the airplane owner's manual, during takeoff or climb from high-altitude airports, the engine should be leaned to achieve maximum rpm; the calculated density altitude at the time of the accident was about 6,552 ft. The manual further stated that, at full throttle climb at altitudes above 5,000 ft, the fuel mixture should be leaned for smooth engine operation. The manual noted that a rough-running engine can result from an improper fuel/air mixture.

Factual narrative

The Grumman American AA-1A, serial number AA1-0209, N5909L, was manufactured in 1969, and was certified under the normal/utility category. It was equipped with a Lycoming O-235-C2C engine. According to the airframe logbook, the last entry dated July 17, 2012, a 100-hr inspection was performed at a tachometer time of 400.06 hours and a total airframe time of 3,891.42 hours. There were no additional entries in the airplane logbook. According to the engine logbook, the last entry dated July 17, 2012, an annual/100-hr inspection was performed at a tachometer time of 400.06 hours, a total time of 3,388.62 hours, and time since major overhaul of 1,946.62 hours. There were no additional entries in the engine logbook. According to the airplane's Owner's Manual, section III Operating Procedures, there was a note that stated in part, that during takeoff or climb from high-altitude airports, the engine should be leaned to achieve best power (maximum rpm). Section V Performance Charts, note, item 1 stated that at a full throttle climb, mixture leaned above 5,000 feet to smooth engine operation. Section VII Care of Airplane indicated that if a rough-running engine was encountered, it may be for any one of the following reasons, of which, one reason was an incorrect fuel/air mixture. According to the FAA's Airport Facility Directory, TRK is at an elevation of 5,901 feet. In the airport remarks section, it stated that a special hazard existed, mountainous terrain surrounds the airport and runways, expect wind shear and downdrafts. On May 23, 2013, about 1210 Pacific daylight time, an American Grumman AA-1, N5909L, lost engine power during the takeoff initial climb out from the Truckee-Tahoe Airport (TRK), Truckee, California, and impacted trees near the Glenshire subdivision in Truckee, about 8 miles east of the airport. The airplane was owned by a private individual and piloted by the commercial pilot who was ferrying the airplane to New York for the new owner. The airplane sustained substantial damage. The pilot, the sole occupant, was ejected from the airplane, and sustained serious injuries. Visual meteorological conditions prevailed for the flight, and no flight plan had been filed. The flight was destined for Derby Field (LOL), Lovelock, Nevada. The pilot was interviewed by a Federal Aviation Administration (FAA) inspector. The pilot stated that he leaned the airplane engine on the ground utilizing the cylinder head temperature (CHT) gauge. After leaning the airplane with the fuel pump on, he commenced with the takeoff. The pilot stated that during the climb, the engine quit, and he thought the airplane was going to stall. The pilot stated that he does not remember anything after the loss of engine power, until he woke up, and crawled to the cockpit to look for his cell phone to alert the authorities of the accident. The pilot called 911 about 1500, requesting assistance. A responding deputy from the Nevada County Sheriff's department stated that thedebris field was about 100 yards in length with the tops of several small trees showing visible signs of impact damage. Both wings separated from the airplane, and were found about 50 feet from the main wreckage. The smell of fuel was present. The deputy reported that the canopy had shattered leaving the cockpit open. In the pilot's written statement, he reported that the airplane was refueled at TRK. He stated that he leaned the airplane for taxi, and on takeoff the mixture was full rich. During climb out the engine quit; the airplane slowed, and wanted to stall. The pilot stated that he did not remember anything else as he had lost consciousness. The fuel receipt indicated that the pilot had refueled the airplane at 11:30, the morning of the accident, with 10.320 gallons of 100 low lead fuel. Weather obtained from the airport indicated that at 1145, wind was from 260 degrees at 7 knots with gust to 14 knots; visibility was 10 statute miles, a broken cloud layer at 7,000 feet, temperature 9 degrees C, dew point -11 degrees C, and altimeter setting 29.97 inches of mercury. Utilizing the temperature, dew point, and altimeter setting, the density altitude at the takeoff location would have been about 6,552 feet. The pilot reported his total time as 1,027.5 total hours with 10 hours in the accident make and model. According to the pilot's logbook, his last flight review was performed on June 6, 2009. The pilot submitted in his NTSB pilot/operator report form 6120.1, that his last flight review was performed on October 30, 2011, in a Cessna 152. Subsequently, the pilot submitted a written statement and logbook entry that verified his last flight review was in October 2011. The airplane and engine were examined on July 16, 2013. A visual examination of the engine revealed no obvious pre impact damage. All of the accessories remained secured in their proper location at the rear of the engine. The top spark plugs, the starter, and the lower cowling were removed to facilitate manual rotation of the propeller to check for engine continuity. No binding was noted when the propeller was rotated, and thumb compression was obtained in all cylinders in the proper firing order. There is a detailed report attached to the public docket for this accident. The examination revealed no mechanical anomalies that would have precluded normal operation.

Aircraft

Registration
N5909L
Reported as
American AA-1
Category
Airplane
Serial number
AA1-0209
Airframe hours
3,891.42
Engine
Lycoming O-235-C2C, 115 horsepower, reciprocating
Damage
Substantial damage
Flight
Ferry · Part 91
Operator
Silva Lawrence Jr
Registered owner
Silva Lawrence Jr
Airworthiness certificate
Standard, Normal
Last inspection
Annual · July 17, 2012
Departed
TRK · Truckee, CA
Destination
LOL · Lovelock, NV
Airport
TRK · Truckee-Tahoe Airport
Equipment
None

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
31
Injuries
Serious
Certificate
Commercial
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 1, Without waivers/limitations
Seat
Left
Flight hours
1,027.5 total · 10 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
280° at 6 knots, gusting 15
Visibility
10 statute miles
Lowest ceiling
7,000 ft broken
Temperature
46 °F, dew point 12 °F
Altimeter
29.95 inHg
Observed at
TRK, 7 nm away

Docket · 12

The files NTSB released with the investigation on March 26, 2014, on NTSB’s docket system: statements, records, photos and specialists’ reports. 8.2 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.