N601ATCessna 550 · 1982

On July 22, 2010, approximately 1100 central daylight time, a Smith Aerostar 601P, N601AT, was substantially damaged when both engines lost power and the pilot was forced to land in a plowed field 2 miles south of Cleburne (CPT), Texas. Visual meteorological conditions prevailed at the time of the accident. The ferry flight was being conducted under the provisions of Title 14 Code of Federal Regulations (CFR) Part 91 without a flight plan. The pilot, the sole occupant on board, sustained minor injuries. The cross-country flight originated at CPT, and was en route to Mena (MEZ), Arkansas.

According to the pilot's accident report, he cycled both fuel selectors and "they both sounded normal through the 3 positions." He found the left engine starter drive engaged, "like someone tried to start (it) and it didn't start." The fuel sumps were drained. During the takeoff, "the fuel pressure came up a couple of pounds when turning on boost pumps, rpm came up to just above 2550, and manifold (pressure) came up to about 30.5 (inches), then back to 29.5 (inches) approximately. After takeoff and upon reaching 700 to 800 feet, the pilot retracted the landing gear and the right engine started losing power. The pilot wrote, "I turned off the boost pump. No power. Turned it back on. Switched to crossfeed on the right. Both boost pumps on. Still no power. Went back to on. Then the left engine lost power.

The pilot steered towards the nearest open field "and was barely able to avoid an automobile and trees and keep from stalling." The airplane impacted terrain near the intersection of Highway 171 and Johnson County Road 312. A television news photo showed a circumferential crack in the airplane's fuselage near the aft pressure bulkhead.

According to the Airplane Flight Manual (AFM) and Supplemental Type Certificate (STC) SA1608NM (Mechen, Inc.), the airplane was equipped with four fuel tanks: integral wet fuel tanks located, in each wing outboard of the engine nacelle (65 gallons total, 62 gallons usable); a rectangular bladder-type fuel tank, located between the rear cabin bulkhead and the forward bulkhead of the baggage compartment (43.5 gallons total, 41.5 gallons usable); an integral metal auxiliary fuel tank, located in the forward section of the baggage compartment (45 gallons total, 44 gallons usable). The airplane was capable of carrying 218.5 gallons of fuel, 209.5 gallons of which were usable.

In his accident report, the pilot said he filled the fuselage tank to capacity, 20 gallons was placed in the auxiliary tank, and 25 gallons was placed in each wing tank (a total of 113.5 gallons). The pilot said there was a total of 131 gallons on board.

An FAA inspector who went to the accident site said the fuel servos, which activate the fuel valves, operated normally when power was applied to the aircraft’s electrical system and the fuel selectors were manipulated. The electric boost pumps also operated normally.

The pilot later sent the following note to the FAA inspector: "I have been trying to figure out why there was no fuel in the fuselage tank, and so much (fuel) in the right wing (tank). I’m not sure I turned the fuel shut off valves to OFF before I turned off the master switch. I guess I was a little shook up. With the right wing lower I believe it could gravity feed."

The airplane’s insurance company hired a salvage retriever to recover the airplane and before it could be moved, the fuel had to be drained from the tanks. The retriever reported the left wing contained 17 gallons of fuel, the right wing contained 57 gallons of fuel, the main fuselage tank contained 2.5 gallons of fuel, and the auxiliary fuselage tank contained 28 gallons of fuel.

After the accident, Varsol was added to the main fuselage tank and auxiliary fuselage tank. Neither tank leaked. The fuel sumps contain check valves which prevent the back-flow of fuel from one fuel tank to another. Further examination revealed the fuselage contained two fuel filler necks, one for each fuselage tank (main and auxiliary). The auxiliary tank was clearly placarded with the red placard visibly standing out against the silver paint stripe. The main tank is not clearly placarded with the red placard blending easily with the red paint stripe.