Location: Soldotna, Alaska
Accident Number: ANC20LA064
Date and Time: July 4, 2020, 15:23 Local
Registration: N3604A
Aircraft: Piper PA22
Aircraft Damage: Substantial
Defining Event: Part(s) separation from AC
Injuries: 1 None
Flight Conducted Under: Part 91: General aviation - Personal
Analysis
In cruise flight, the private pilot heard and felt a “pop” emit from the airplane. He immediately noticed the airplane descending but verified he still had elevator continuity. Unable to maintain altitude, the pilot made an emergency landing on a nearby paved road; however, the airplane landed hard, and the main landing gear collapsed.
Postaccident examination revealed control continuity, but it was noted that the adhesive adhering the fabric above the windscreen had separated.
FAA Airworthiness Directive (AD) 74-17-04 applies to certain Piper airplanes, including PA-22 series airplanes that are covered with cotton or linen, and was issued to prevent the sudden failure of the material at the top of the windshield by requiring the installation of a reinforcement metal strip. Because the accident airplane was covered in a heavy-duty polyester material, the hardware specified in the AD was not required for installation on the airframe nor was it installed.
It is likely that the adhesive adhering the fabric above the windscreen delaminated and disrupted the airflow over the airplane. It was not determined why the adhesive failed/delaminated.
Probable Cause and Findings
The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The delamination of the fabric material from the fuselage above the windscreen due to failed adhesive, which resulted in disrupted airflow and a subsequent hard landing.
Findings
Aircraft Fuselage main structure - Failure
Personnel issues Aircraft control - Pilot
Aircraft Landing flare - Unknown/Not determined
Factual Information
On July 4, 2020, about 1523 Alaska daylight time, a Piper PA-22 airplane, N3604A, was substantially damaged when it was involved in an accident near Soldotna, Alaska. The private pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.
The pilot reported that once established in a cruise flight configuration, around 1,300 ft mean sea level (msl), he heard and felt a “pop” emit from the airplane. He immediately noticed the airplane was descending and verified that he still had elevator continuity by looking back at the empennage. The elevator was not “stuck”, but he was unable to maintain altitude. He made an emergency landing on a nearby paved roadway, but during the touchdown, the airplane landed hard and the main landing gear collapsed. The airplane sustained substantial damage to the left wing, both wing struts, and the fuselage.
A Federal Aviation Administration (FAA) aviation safety inspector examined the airplane after recovery and reported that the flight control cables were intact, and that flight control continuity was established. The inspector noted that the area above the windscreen where the fabric was connected to the fuselage had separated. He also indicated that the fabric did not tear; rather, the adhesive that held the fabric to the structure delaminated. FAA Airworthiness Directive (AD) 74-17-04, dated April 11, 1977, and applicable to certain Piper airplane 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 was issued to prevent the sudden failure of the material at the top of the windshield by requiring the installation of a reinforcement metal strip. The accident airplane was covered in Ceconite 101, a heavy-duty polyester material. The AD hardware was not installed on the airframe of the accident airplane nor was it required to be.
History of Flight
Enroute Part(s) separation from AC (Defining event)
Enroute Loss of control in flight
Emergency descent Attempted remediation/recovery
Landing Hard landing
Pilot Information
Certificate: Private
Age: 32, Male
Airplane Rating(s): Single-engine land
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used: 4-point
Instrument Rating(s): None
Second Pilot Present: No
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 3 With waivers/limitations
Last FAA Medical Exam: June 14, 2017
Occupational Pilot: No
Last Flight Review or Equivalent:
Flight Time: (Estimated) 336 hours (Total, all aircraft), 237 hours (Total, this make and model), 258 hours (Pilot In Command, all aircraft), 73 hours (Last 90 days, all aircraft), 31 hours (Last 30 days, all aircraft)
Aircraft and Owner/Operator Information
Aircraft Make: Piper
Registration: N3604A
Model/Series: PA22 135
Aircraft Category: Airplane
Year of Manufacture: 1953
Amateur Built:
Airworthiness Certificate: Normal
Serial Number: 22-1864
Landing Gear Type: Tailwheel
Seats: 2
Date/Type of Last Inspection: Annual
Certified Max Gross Wt.: 2000 lbs
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time:
Engine Manufacturer: Lycoming
ELT: C91 installed, activated, did not aid in locating accident
Engine Model/Series: O-320B
Registered Owner:
Rated Power: 150 Horsepower
Operator: On file
Operating Certificate(s) Held: None
Meteorological Information and Flight Plan
Conditions at Accident Site: Visual (VMC)
Condition of Light: Day
Observation Facility, Elevation: PASX, 113 ft msl
Distance from Accident Site: 3 Nautical Miles
Observation Time: 14:56 Local
Direction from Accident Site: 298°
Lowest Cloud Condition: Clear
Visibility: 10 miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: 8 knots /
Turbulence Type Forecast/Actual: /
Wind Direction: 280°
Turbulence Severity Forecast/Actual: /
Altimeter Setting: 30.05 inches Hg
Temperature/Dew Point: 24°C / 13°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Sterling, AK (AK84)
Type of Flight Plan Filed: None
Destination: Homer, AK (HOM)
Type of Clearance: None
Departure Time: 15:17 Local
Type of Airspace: Class G
Wreckage and Impact Information
Crew Injuries: 1 None
Aircraft Damage: Substantial
Passenger Injuries:
Aircraft Fire: None
Ground Injuries:
Aircraft Explosion: None
Total Injuries: 1 None
Latitude, Longitude: 60.45,-150.93333(est)
Location: Soldotna, AK
Accident Number: ANC20LA064
Date & Time: 07/04/2020, 1523 AKD
Registration: N3604A
Aircraft: Piper PA22
Injuries: 1 None
Flight Conducted Under: Part 91: General Aviation - Personal
On July 4, 2020, about 1523 Alaska daylight time, a Piper PA-22 airplane, N3604A, was substantially damaged when it was involved in an accident near Soldotna, Alaska. The private pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.
The pilot reported that once established in a cruise, level flight configuration, around 1,300 ft mean sea level (msl), he heard and felt a "pop" that appeared to emanate from somewhere in the airplane. He said that the airplane then began a shallow, uncommanded descent, and the elevator began to "flutter." The pilot noted that the elevator was not "stuck", but he was unable to maintain altitude. The pilot subsequently selected a paved, rural neighborhood road as an emergency landing site. During touchdown, the airplane landed hard, and the main landing gear collapsed, sustaining substantial damage to the left wing, both wing lift struts, and the fuselage.
A Federal Aviation Administration (FAA) aviation safety inspector examined the airplane after recovery and reported that flight control continuity was established. The inspector noted that the area above the windscreen, where the fabric was connected to the fuselage, had separated. He also indicated that the fabric did not tear, rather the adhesive that held the fabric to the structure failed, and a portion of the fabric peeled aft.
