Accident Narrative
On July 22, 2010, at approximately 1100 central daylight time, a Smith Aerostar 601P, registration N601AT, experienced a loss of power in both engines during a ferry flight. The pilot executed a forced landing in a plowed field about 2 miles south of Cleburne, Texas (CPT). Visual meteorological conditions prevailed at the time. The flight was conducted under 14 CFR Part 91 without a flight plan. The pilot, the sole occupant, sustained minor injuries, and the aircraft sustained substantial damage. The flight had originated at Cleburne and was en route to Mena, Arkansas (MEZ).
According to the pilot's report, he cycled both fuel selectors and heard normal sounds through the three positions. The left engine starter drive was found engaged, suggesting a previous attempt to start the engine failed. Fuel sumps were drained before departure. During takeoff, fuel pressure increased slightly when boost pumps were activated, engine RPM rose to just above 2550, and manifold pressure reached about 30.5 inches before settling to approximately 29.5 inches. After takeoff, at an altitude of 700 to 800 feet, the pilot retracted the landing gear, and the right engine began losing power. The pilot turned off the boost pump, then back on, switched to crossfeed on the right, turned both boost pumps on, but power did not return. Subsequently, the left engine also lost power.
The pilot maneuvered toward the nearest open field, narrowly avoiding an automobile and trees while preventing a stall. The airplane impacted terrain near the intersection of Highway 171 and Johnson County Road 312. A television news photograph showed a circumferential crack in the fuselage near the aft pressure bulkhead.
Fuel System Configuration
The airplane's fuel system, per the Airplane Flight Manual and Supplemental Type Certificate SA1608NM (Mechen, Inc.), included four tanks: integral wet fuel tanks in each wing outboard of the engine nacelle (65 gallons total, 62 gallons usable), a rectangular bladder-type tank between the rear cabin bulkhead and the forward bulkhead of the baggage compartment (43.5 gallons total, 41.5 gallons usable), and an integral metal auxiliary tank in the forward section of the baggage compartment (45 gallons total, 44 gallons usable). Total fuel capacity was 218.5 gallons, with 209.5 gallons usable.
The pilot reported filling the fuselage tank to capacity, adding 20 gallons to the auxiliary tank, and 25 gallons to each wing tank, for a total of 113.5 gallons. He noted the total fuel on board was 131 gallons.
Post-Accident Examination
An FAA inspector examined the aircraft at the accident site. With electrical power applied and the fuel selectors manipulated, the fuel servos operated normally. The electric boost pumps also functioned normally.
After recovery, a salvage retriever drained the fuel tanks. Measurements showed the left wing contained 17 gallons, the right wing 57 gallons, the main fuselage tank 2.5 gallons, and the auxiliary fuselage tank 28 gallons.
Varsol was added to both fuselage tanks, and no leaks were detected. Fuel sumps are equipped with check valves to prevent back-flow between tanks. The fuselage had two fuel filler necks, one for each tank. The auxiliary tank filler neck was clearly placarded with a red placard that stood out against the silver paint stripe, while the main tank placard blended with the red paint stripe.
In a note sent to the FAA inspector, the pilot stated he was unsure whether he had turned the fuel shutoff valves to OFF before turning off the master switch. He speculated that because the right wing was lower, fuel could have gravity-fed from the fuselage tank to the right wing tank.