ERA10CA353

NTSB accident investigation · Lawwill Ted Zodiac 601XL · Waddy, KY · June 29, 2010

Accident · No injuriesData collectionFinal report
Date
June 29, 2010, 15:30 local (19:30 UTC)
Place
Waddy, KY
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N601LPLawwill Ted Zodiac 601XL
Defining event
Enroute-cruise: Fuel starvation
Weather
Visual (VMC) · Day
Status
Completed · report March 16, 2011
Report
Approved by Office Director
NTSB office
Eastern Region Aviation
Parties
FAA/ FSDO
FAA report
20100629036709A
Case key
76577

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

A loss of engine power due to fuel starvation for undetermined reasons.

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.

Action: incorrect action performancePersonnel issues › Action/decision · Instructor/check pilotLawwill Ted ZODIAC 601XL: 1 caseAll aircraft: 1,386 casesProbable cause
Fluids: fuelAircraft › Fluids/misc hardware · Fluid managementLawwill Ted ZODIAC 601XL: 1 caseAll aircraft: 1,695 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 certificated flight instructor (CFI) stated that he was the pilot-in-command and safety pilot because the other pilot had not flown in about eight months. Preflight inspection of the airplane revealed each fuel tank was half full, which was adequate for the planned one hour flight plus a reserve. After takeoff, the flight proceeded to another airport, where two uneventful touch-and-go practice takeoff and landings were performed. The pilots then elected to return to the original departure airstrip flying about 800 feet above ground level. During the return flight, the CFI noticed that the single fuel gauge, which only indicated fuel quantity from the selected tank, indicated less than one quarter tank of fuel remaining in the left tank. He then selected the right tank to supply the engine. The engine operated normally for less than a minute before beginning to sputter. The CFI immediately switched back to the left fuel tank, turned on the electric fuel pump, and applied carburetor heat. The engine regained power and the airplane began to climb, but the engine subsequently experienced a total loss of power. During the descent, the CFI switched to the right tank again. The engine did not regain power and the performed a forced landing to a grassy hill. During landing, the nose gear sheared and one wing incurred substantial damage. At the time of the airplane's wreckage recovery, no fuel was noted in the left tank and about eight gallons of fuel was drained from the right fuel tank; there was no breach of fuel lines or fuel tanks. The fuel strainer contained fuel; however, there was no fuel at the fuel selector valve located in the cockpit or in fuel lines from the fuel strainer to the engine. The CFI opined that the engine lost power due to the left tank becoming exhausted of fuel, which introduced air into the fuel supply system. A subsequent ground test indicated that with the electric pump on, the supply system should have been purged of air in about three seconds.

Factual narrative

The certificated flight instructor (CFI) stated that he was the pilot-in-command and safety pilot because the other pilot had not flown since November 2009. Preflight inspection of the airplane revealed each fuel tank was half full, which was adequate for the planned 1 hour flight plus reserves. After takeoff, the flight proceeded to another airport, where two uneventful touch-and-go landings were performed. The pilots then elected to return to the original departure airstrip flying about 800 feet above ground level. During the return flight, the CFI noticed that the single fuel gauge, which only indicated fuel quantity from the selected tank, indicated less than one quarter tank of fuel remaining in the left tank. He then selected the fuel from the right tank; however, the engine ran normally for "less than a minute" before beginning to “sputter.” The CFI immediately switched back to the left fuel tank, turned on the electric fuel pump, and applied carburetor heat. The engine regained power and the airplane began to climb, but the engine then lost all power. During the descent, the CFI switched to the right tank again; however, the engine did not regain power, and he performed a forced landing to a grassy hill where the nose gear sheared and one wing incurred substantial damage. During the recovery of the airplane, no fuel was noted in the left tank, about 8 gallons of fuel were drained from the right fuel tank, and there was no breach of fuel lines or fuel tanks. The fuel strainer contained fuel; however, there was no fuel at the fuel selector valve located in the cockpit or in fuel lines from the fuel strainer to the engine. When asked why he thought the engine failed, the CFI stated that he thought he ran the left tank dry and introduced air into the fuel supply system. A subsequent ground test indicated that with the electric pump on, the supply system should have been purged of air in about 3 seconds.

Aircraft

Registration
N601LP
Reported as
Lawwill Ted Zodiac 601XL
Category
Airplane, amateur-built
Serial number
6-5230
Airframe hours
161
Engine
Lycoming O-235-L2C, 118 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Airworthiness certificate
Special, Experimental (Special); Standard, Normal
Last inspection
Annual · May 8, 2010
Departed
FFT · Frankfort, KY
Destination
Waddy, KY

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
Flight instructor
Age
25
Injuries
None
Certificates
Commercial, Flight instructor
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 1, Without waivers/limitations
Last flight review
May 4, 2009
Seat
Right
Flight hours
799 total · 1 in this make and model · 295 as pilot in command · 56 in the last 90 days · 11 in the last 30 days
Role
Student pilot
Age
76
Injuries
None
Certificate
Airline transport
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Sport pilot
Last flight review
November 9, 2009
Seat
Left
Flight hours
5,000 total · 5 in this make and model · 3,000 as pilot in command · 1 in the last 90 days · 1 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
250° at 6 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
82 °F, dew point 63 °F
Altimeter
30.03 inHg
Observed at
FFT

Docket · 4

The files NTSB released with the investigation on October 7, 2010, on NTSB’s docket system: statements, records, photos and specialists’ reports. 1.1 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.