On July 12, 1998, a Cessna 170B (registration N3018A) was involved in an aviation accident near Hailey, ID. Investigators recorded the probable cause as: The pilot-in-command's failure to maintain directional control during takeoff. Contributing factors were the pilot-in-command's failure to follow procedures by the improper use of the flaps, high density altitude conditions, crosswind conditions and the tree. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During takeoff from a 6,600-foot paved runway with 20 degrees of flaps, the aircraft veered left, crossed a highway, clipped trees, and came to rest in a subdivision. Winds were from 200 degrees at 7 knots, and density altitude was 7,630 feet.
Takeoff and Initial Climb
The pilot initiated takeoff from runway 13, a 6,600-foot paved runway. Shortly after becoming airborne, the aircraft veered left, flew low, and then gained enough altitude to cross a highway and fly over power lines located east of the highway.
Collision with Terrain
The aircraft subsequently clipped trees and went nose-first into a subdivision.
Investigation Findings
The investigation revealed that the pilot had departed with 20 degrees of flaps. According to the aircraft owner's manual, the use of flaps is not recommended for crosswind takeoffs. The reported winds were from 200 degrees magnetic at 7 knots. The calculated density altitude at the airport at the time was 7,630 feet.