Incident Overview
On July 4, 2020, at about 1523 Alaska daylight time, a Piper PA-22 airplane, registration N3604A, was substantially damaged when it was involved in an accident near Soldotna, Alaska. The private pilot, who was the sole occupant, reported no injuries. The flight was being conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight.
Sequence of Events
According to the pilot, while cruising at approximately 1,300 ft mean sea level (msl), he heard and felt a "pop" emanating from the airplane. He immediately noticed the airplane descending. He verified that the elevator was not stuck by looking back at the empennage and confirmed control continuity. Unable to maintain altitude, he executed an emergency landing on a paved roadway. During touchdown, the airplane landed hard, causing the main landing gear to collapse.
Post-Accident Examination
After recovery, a Federal Aviation Administration (FAA) aviation safety inspector examined the airplane. The inspector reported that the flight control cables were intact and flight control continuity was established. However, the area above the windscreen where the fabric connected to the fuselage had separated. The fabric itself did not tear; instead, the adhesive holding the fabric to the structure had delaminated.
Relevant Airworthiness Directive
FAA Airworthiness Directive (AD) 74-17-04, issued April 11, 1977, applies to certain Piper models, including PA-22 series airplanes, that are covered with cotton or linen at the critical area on top of the windshield where the fabric attaches to the structure. The AD was issued to prevent sudden failure of the material at the top of the windshield by requiring installation of a reinforcement metal strip. The accident airplane was covered in Ceconite 101, a heavy-duty polyester material. The hardware specified in AD 74-17-04 was not installed on the accident airplane's airframe, nor was it required to be.
Damage
The airplane sustained substantial damage to the left wing, both wing struts, and the fuselage.