DEN02LA064

The pilot took off at 0638, drawing fuel from the left main tank. At 0739, he switched to the right main tank. At 0840, he switched to the auxiliary fuel tank. As he approached his destination, the pilot noted that the main fuel tanks were half full and the auxiliary fuel tank was over half full. He reduced power and began a slow descent. As he approached the traffic pattern, he switched back to the left main fuel tank. On approach, he lowered the landing gear and as he started to lower the flaps, he noticed the airspeed had decreased so he added power. The airplane "started to wobble and became hard to handle," so the pilot applied full power. The airspeed "was not responding very quickly." He confirmed the fuel selector was on the left tank and the fuel boost pump was on. After clearing a rock wall cliff and ravine, the pilot flew underneath power lines and the airplane struck the ground. Flow testing of the carburetor at 10 pounds psi revealed an external leak at the idle diaphragm. Further tests indicated the carburetor would run rich at low power settings and lean at high power settings. The fuel pump was able to maintain 20 gph at 10 psi and 500 rpm. At 1,000 rpm, a leak was noted at the lower splitline surface. At 2,500 rpm, the fuel pump maintained 160 gph at 12 psi.

On June 29, 2002, at 1013 mountain daylight time, a Beech 35, N404B, registered to and operated by the pilot, was substantially damaged when it struck the terrain during an uncontrolled descent at Cortez, Colorado. The private pilot received minor injuries, but his passenger was seriously injured. Day visual meteorological conditions prevailed, and no flight plan had been filed for the personal cross-country flight being conducted under Title 14 CFR Part 91. The flight originated at Winslow, Arizona, at 0638.

According to the pilot's accident report, he departed Ryan Airfield at 0638 Pacific daylight time, en route to Bedrock, Colorado, northwest of Nucla, via Winslow, Arizona, and Cortez, Colorado. Fuel was drawn from the left main tank. At 0739, the pilot switched to the right main tank. At 0840, the pilot switched to the auxiliary fuel tank. The pilot said that the main fuel tanks were one-half full and the auxiliary fuel tank was over one-half full as he approached Cortez Airport. When he was 9 miles from the airport, he reduced power and began a 500 fpm (feet per minute) descent. As he approached the traffic pattern, he switched back to the left main fuel tank. Midfield, on the downwind leg, he slowed the airplane to 100 mph and lowered the landing gear. He turned onto the base leg, then onto the final approach. When he started to lower the flaps, he noticed the airspeed had dropped from 85 to 80 mph and he added power. The pilot said the airplane "started to wobble and became hard to handle," so he applied full power. The airspeed "was not responding very quickly." He confirmed the fuel selector was on the left tank and the fuel boost pump was on. Fuel pressure read 7 psi (pounds per square inch). "The airplane was becoming extremely hard to handle," he wrote. After clearing a rock wall cliff and ravine, the pilot saw power lines ahead. He pushed the nose down to increase airspeed and flew underneath the wires [Witnesses told the FAA inspector that the airplane appeared to stall]. When he applied back pressure on the control yoke, the airplane would not pull up and struck the ground and spun around. The pilot said he found the right cabin door open and his wife missing. She was found on the ground nearby. Evidence at the site indicated the airplane struck the ground in a right wing low, nose low attitude and skidded 75 feet. The passenger's seatbelt was found unfastened.

On August 6, 2002, the fuel pump and carburetor were bench checked at Airmotive Carburetor Company under the auspices of an FAA inspector. Flow testing at 10 pounds per square inch (psi) revealed an external leak at the idle diaphragm. Further tests indicated the carburetor would run rich at low power settings and lean at high power settings. The fuel pump was test run at 500 rpm and it maintained 20 gallons per minute (gph) at 10 psi. At 1,000 rpm, an "excessive" external leak was noted at the lower splitline surface. At 2,500 rpm, the fuel pump maintained 160 gph at 12 psi.