It seems so simple: Read a line and do what it says. Verify that it has been done correctly before going to the next thing. If you’re interrupted, start over. For decades, aviation has relied on checklists as a fundamental step in risk management, and now disciplines from auto repair to trauma surgery are coming to recognize their value.
As we’ve heard, “a checklist is not a to-do list.” Experienced pilots may develop a flow that they find more efficient but still refer to the written checklist for confirmation. Extensive time in one model or even a single aircraft may entice some to run checklists from memory, with the accompanying risk of missing a crucial step. While still new to the aircraft, however, there’s much to be said for following the checklists exactly as written.
On Jan. 28, 2009, a Siai-Marchetti SF-260 lost power on initial climb-out from Santa Monica, Calif. According to witnesses, the engine stopped at an altitude of about 400 feet; the airplane began a right turn and then spun into the ground beside the runway. The 1,600-hour private pilot and his passenger were both killed.
The wreckage was confined to a 50-foot area around the point of impact. The post-crash fire did severe damage to both wings and the fuselage, and made it impossible to test the magnetos, ignition harness, or fuel pump. Those engine components that could be examined showed no evidence of failure or malfunction.
The fuel selector was initially thought to have been set to the right tip tank. More careful examination concluded that it was actually between the detents for the right tip and right main tanks, but had probably been displaced from the tip-tank position by the impact.
The last pilot who had flown the airplane recalled having filled the mains at the self-service pump, and then used the right tip tank to taxi back to the hangar, which he described as “standard operating procedure in this airplane.” He also noted that while he wasn’t sure how much fuel was in the tips, there wasn’t much.
There are some airplanes—the Cessna 300 series, for example—in which the tip tanks are the mains, and misunderstood fueling instructions have led to shortages at inconvenient times. Most other airplanes with tip tanks use them to carry reserves, either replenishing the mains via transfer pumps or drawing directly from the tips in cruise. The SF-260 falls into the latter category. The flight manual specifies selecting the left main before engine start and restricts use of the tip tanks to level flight. Just in case the pilot hasn’t glanced at the checklists recently, a placard on the instrument panel reads, in all capital letters, “Use wing tip tanks in level flight only.”
The accident pilot had been added to the SF-260’s insurance policy the previous May. At that time, he had claimed five hours of make-and-model experience. The airplane’s owner estimated that the pilot had logged about 15 more hours over the intervening eight months. Not bad—but not enough to trust entirely to memory.
Whether the pilot never ran the checklist, got distracted and missed a step, or decided he was qualified to improvise doesn’t matter in the end. What’s clear is that the checklist was never accomplished. As a result, the pilot missed an essential step of the preflight procedure and tried to take off without connecting the engine to a tank that would deliver fuel. The final cost of that single, simple oversight was two lives.