Accident Overview
On May 31, 2015, at about 2000 Alaska daylight time, a tailwheel-equipped Piper PA-22, N2828P, was substantially damaged after impacting terrain while maneuvering at low level approximately 17 miles southeast of Skwentna, Alaska. The student pilot, the sole occupant, sustained minor injuries. The aircraft was operated under 14 CFR Part 91 as a personal cross-country flight. Visual meteorological conditions prevailed, and no flight plan was filed.
Pilot Statement
During an interview with the National Transportation Safety Board (NTSB) investigator-in-charge on June 1, 2015, the pilot reported that he was maneuvering to "drag the runway" of an unimproved airstrip. After passing over some trees in a northerly direction, the airplane began a rapid descent. The pilot applied full power to correct for the descent, but the engine power decreased. About 25 feet above ground level, the left wing struck a tree, and the airplane impacted terrain in a slight left bank. The airplane slid along the surface for about 18 feet before impacting a berm, which caused the airplane to become airborne and rotate counterclockwise 180 degrees before coming to rest in a near level pitch attitude.
Post-Accident Examination
Post-accident examination of the airplane and its maintenance records revealed that Federal Aviation Administration (FAA) Airworthiness Directive (AD) 73-09-06 was applicable to Piper PA-22-150 airplanes with Lycoming O-320 series engines and Marvel Schebler Carburetors Model MA-4-SPA, part numbers 10-3678-11, 10-3678-12, and 10-3678-32. The accident airplane was equipped with a Lycoming O-320 engine and a Marvel Schebler Carburetor, model number MA-4SPA, P/N 10-3678-32, and the airplane was in compliance with the AD by having the required placard in place at the time of the accident.
Airworthiness Directive
AD 73-09-06 states: "To prevent power interruption and acceleration hangup resulting from abrupt throttle movement, accomplish the following: Attach the following operating limitation placard to the instrument panel near the throttle in full view of the pilot. Use 1/8 inch min. size lettering. 'DO NOT OPEN THROTTLE RAPIDLY – (IDLE TO FULL THROTTLE, 2 SECONDS MINIMUM)' The placard may be fabricated by the owner or operator." The pilot stated that when he advanced the throttle, he did so in a rapid motion, faster than the 2-second requirement.
Weather
The closest weather reporting facility, Skwentna Airport, about 17 miles northwest of the accident site, reported at 1850: winds from 290 degrees at 7 knots; visibility, 30 statute miles; sky condition, few clouds at 3,500 feet, scattered at 20,000 feet; temperature 77 degrees F; dewpoint 37 degrees F; barometric pressure 29.74 inHg.