Aircraft: Piper Cherokee. Injuries: 1 Minor. Location: Buena Vista, Colo. Aircraft damage: Substantial.
What reportedly happened: The airplane lifted off at a little over 60 knots and was initially sluggish to climb, so the pilot lowered the nose to gain more speed in ground effect.
The airplane accelerated to about 70 knots and started to gain some altitude, so the pilot continued the departure. Shortly after clearing the end of the runway, the engine lost power and began to descend.
The pilot saw trees and houses ahead and realized that the airplane did not have sufficient altitude to clear them, so he decided to land in a field with deep grass just north of the airport. Upon landing the nose landing gear collapsed.
After the accident, the pilot reported that he believed that he may not have leaned the engine enough during run-up, resulting in less than 100% available power to climb. He also reported that the spark plugs may have been fouled due to the mixture setting, resulting in the loss of available power immediately after takeoff.
The plane was loaded to within 65 pounds of its maximum gross weight and with a calculated density altitude of 10,400 feet, the anticipated climb rate of 300 feet per minute required full power as outlined in the Pilot’s Operating Handbook. The pilot noted that, if there were not deep grass in the landing field, he could have landed the airplane without incident.
Probable cause: The airplane’s diminished climb performance due to the pilot not leaning the engine mixture enough prior to takeoff in high density altitude conditions and at nearly maximum gross takeoff weight.
NTSB Identification: CEN11CA678
This September 2011 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it isintended to help pilots learn from the misfortunes of others.