On October 29, 1989, a Cessna 177 (registration N30036) operated by Rdl Inc. was involved in an aviation accident near Mchenry, MD. Investigators recorded the probable cause as: THE PILOT'S FAILURE TO OBTAIN ADEQUATE TAKEOFF AIRSPEED AS A RESULT OF AN IMPROPER FLAP SETTING. CONTRIBUTING FACTORS WERE A TAKEOFF WITH A TAILWIND, AN UPSLOPING RUNWAY, AND HIGH DENSITY ALTITUDE. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
An aircraft experienced a slow climb and rolled left and right after takeoff with variable wind conditions, then pitched down and crashed. Examination revealed flaps were fully extended.
Accident Sequence
Witnesses reported that the aircraft took off under wind conditions that varied from a left crosswind to a left quartering tailwind. The runway slopes upward, and beyond its end, the terrain slopes downward. According to witnesses, although the aircraft climbed slowly and rolled left and right several times, the engine was operating throughout the flight. The aircraft abruptly pitched down, descended, and crashed.
Aircraft Examination
Post-accident examination of the aircraft revealed that the flaps were extended 30 degrees, which is the full down position. According to aircraft performance data, the best rate of climb with 30 degrees of flaps is approximately 310 feet per minute under standard temperature conditions. The density altitude at the time of the accident was computed to be about 4,000 feet.