LAX00LA021

NTSB accident investigation · Cessna 172N · Deer Valley, AZ · October 21, 1999

Accident · No injuriesLimited investigationFinal report
Date
October 20, 1999, 18:19 local (Oct 21, 1999, 01:19 UTC)
Place
Deer Valley, AZ
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N738FYCessna 172N
Weather
Visual (VMC) · Night/dark
Status
Completed · report April 6, 2001
Report
Approved by Office Director
FAA report
19991020030779A
Case key
47672

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

Fuel exhaustion due to the pilot's inadequate preflight verification of the fuel quantity, and, once he became aware of the critical fuel state, his decision to over-fly two alternate airports in order to continue to his destination.

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(total) - nonmechanicalDescent
Fluid,fuel - exhaustion
Aircraft preflight - inadequatePilot in commandCause
Fuel supply - not verifiedPilot in commandCause
Flight to destination alternate - not performedPilot in commandCause
Forced landingEmergency descent/landing
On ground/water collision with objectLanding - roll
Object - tree(s)

Analysis

After flying 4.4 Hobbs hours since the last fueling, the engine lost power and the airplane collided with a tree in the ensuing forced landing. Fueling records show the airplane was fueled the day before the accident, and then another renter pilot flew the airplane for 1.3 hours without refueling. The pilot did a preflight of the airplane and checked the left wing tank for fuel by sticking his finger in the filler opening. He did not check the right fuel tank. He noted that the left fuel gauge read full and the right fuel gauge read 3/4 of a tank when he departed. The pilot flew north to Flagstaff and then returned to the local Phoenix area and practiced a touch-and-go at a nearby airport while he waited for the sun to set. He noticed that the fuel gauge needles were not moving, which in his mind may have been an indicator of a low fuel state; however, he said he felt the gauges were inaccurate instead. He elected to continue his flight back to the originating airport, bypassing two airports along the way. The pilot was northeast of the second possible alternate airport when the engine sputtered the first time. He elected to continue his flight towards the destination airport, 12 miles further on, rather than perform a precautionary landing. The engine then lost all power and the pilot executed a forced landing in a clear area. During the landing roll, the airplane collided with a small tree. The airplane's Hobbs meter readings show the pilot flew the airplane for 3.1 hours on the accident flight, for a total of 4.4 hours since the last refueling.

Factual narrative

On October 20, 1999 at 1819 hours mountain standard time, a Cessna 172N, N738FY, collided with a tree following a forced landing near Deer Valley, Arizona. The airplane, operated by Westwind Aviation, sustained substantial damage. The private pilot and his passenger were not injured. The personal flight was operated under 14 CFR Part 91. The pilot did not file a flight plan for the flight. The airplane departed Deer Valley at 1530 on a round-robin flight to Flagstaff, Arizona, and returning to Deer Valley. Visual meteorological conditions prevailed at the time of the accident.

The pilot said he did a preflight and checked the left wing tank by sticking his little finger in to see if it came out wet, it did, and at this time he believed he had full fuel tanks. He did not check the right fuel tank. After completing his outside preflight, he started the engine and looked at the gauges. He said the left wing gauge indicated "full" and the right wing indicated "3/4 full." The pilot departed Deer Valley airport and began a climb to 7,000 feet. He said they passed by Sedona and climbed to 9,000 feet and headed north towards Flagstaff. He then climbed to 12,500 feet and flew around Mt. Humphrey's before he started back toward Phoenix.

He said he flew to the Phoenix Gateway airport to wait for the sun to set, and did a touch-and-go, and then climbed to 4,000 feet. At this point, he noticed that both float gauges had "stopped bouncing." He said that the bouncing fuel gauges indicated that there is "something in the tank," and a lack of movement may be an indicator of a low fuel state. He said that he felt his options at this point were to proceed to Falcon Field or to head back to Deer Valley airport. He said he felt the gauges had to be wrong.

The pilot was northeast of Scottsdale when the engine began to sputter. He dialed in 7700 on his transponder and the engine began to run again. He said he had just crossed Scottsdale road when the engine quit a second time. He stated in his written report that he should have landed at Scottsdale airport, but that there were many houses, and it was the end of rush hour. He elected to continue towards Deer Valley airport.

Maricopa Sheriff's officers, who were in the area in their helicopter, said they overheard the pilot tell Air Traffic Control that "he had found some fuel somewhere" as he got the engine started a second time. The sheriff's pilot stated the pilot told the Deer Valley control tower that he ran out of fuel and had to make an off-airport forced landing. The sheriff's officers in the helicopter were asked to assist the airplane in finding a safe place to land and lit up the area for the pilot while he landed on the roadway, approximately 3 1/2 miles northeast of the airport. The airplane struck a small tree during the off-airport forced landing.

According to the operator's records, the airplane had been fueled on the day before the accident, with a total of 21.0 gallons of fuel. Another renter flew it for 1.3 hours and did not refuel the airplane. The Hobbs meter readings show the accident pilot then flew the airplane for 3.1 hours.

Aircraft

Registration
N738FY
Reported as
Cessna 172N
Category
Airplane
Serial number
17269954
Airframe hours
2,056
Engine
Lycoming O-360-A4M, 160 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Westwind Aviation Inc, doing business as Westwind Aviation
Registered owner
Magnetic West LLC
Airworthiness certificate
Standard, Normal
Last inspection
Annual · September 28, 1999 · 32 hours before
Departed
DVT · AZ

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
Medical
Class 3, Valid Medical--w/ waivers/lim
Seat
Left
Flight hours
86 total · 16 in this make and model · 45 as pilot in command · 5 in the last 90 days · 3 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Night/dark
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
None
Temperature
82 °F, dew point 39 °F
Altimeter
30.00 inHg
Observed at
DVT, 3 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.