As pilots, we are trained to handle most emergencies based on checklist procedures, but what happens when there is no checklist? The mantra is "aviate, navigate, communicate." If we don't fly the airplane, the rest doesn't matter. When a door or engine cowl cover opens in flight, it is a distraction, but not usually something that will by itself cause an airplane to crash.
On April 28, 2001, a Beech Bonanza crashed on approach following an in-flight opening of the left side engine cowl cover on takeoff at the Newport State Airport in Middletown, RI. Both the pilot and his passenger were killed.
Shortly after takeoff, the pilot contacted Providence departure control stating "I've got a bit of a problem here on takeoff I'm gonna have to go back around and close a cowl flap." The controller asked if the pilot needed assistance, and was told no. He then cleared the pilot for the visual approach.
The pilot announced that he was making a "rather emergency landing at 4 at Newport." Three witnesses stated that the aircraft was low and slow. They all said the airplane appeared to be just above stall speed, and about 100 feet above the ground on base leg. They then witnessed the airplane bank sharply to the left and crash into a field.
The pilot's flight instructor told investigators she had flown the airplane with the pilot a few days earlier, and the same cowling cover had opened prior to takeoff. After securing the cover, it did not open again during that flight.
According to the NTSB, the cause of this accident was the pilot's failure to maintain airspeed. It's clear that the distraction of the engine cowl flap opening was a factor.
For more information about handling distractions while flying, see Bruce Landsberg's September 2001 "Safety Pilot" article " Driven to Distraction" from AOPA Pilot magazine.
Accident reports can be found in ASI's accident database.