Wednesday, August 7, 2019

Structural Icing: Piper PA-32-260 Cherokee Six, N4261T; accident occurred January 16, 2017 near Pilot Point Airport (PAPN), Alaska

The National Transportation Safety Board did not travel to the scene of this accident.

Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office; Anchorage, Alaska
 
Aviation Accident Factual Report - National Transportation Safety Board: https://app.ntsb.gov/pdf


Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms

http://registry.faa.gov/N4261T

Location: Pilot Point, AK
Accident Number: ANC17TA015
Date & Time: 01/16/2017, 1520 AKS
Registration: N4261T
Aircraft: PIPER PA-32
Aircraft Damage: Substantial
Defining Event: Structural icing
Injuries: 2 Serious
Flight Conducted Under: Part 135: Air Taxi & Commuter - Non-scheduled

On January 16, 2017, about 1520 Alaska standard time, a Piper PA-32-260 airplane, N4261T, was substantially damaged during a forced landing to snow-covered terrain about 5 miles south of the Pilot Point Airport (PNP), Pilot Point, Alaska. The airline transport pilot and sole passenger sustained serious injuries. The airplane was registered to a private individual and operated by Van Air Inc., Dillingham, Alaska, as a Title 14 Code of Federal Regulations Part 135 commercial on-demand passenger flight. A visual flight rules (VFR) flight plan was filed and activated. Day instrument meteorological conditions prevailed at the time of the accident. The flight departed PNP about 1505 destined for Port Heiden Airport (PTH), Port Heiden, Alaska.

The pilot stated that the chartered passenger flight originated from Dillingham Airport (DLG), Dillingham, about 1350 destined for PTH with one passenger. While en route over the Pilot Point area, at an altitude of 800 feet and about 48 miles from the destination, the windshield started accumulating trace ice. The pilot landed the airplane at PNP and called the PTH village agent who reported the destination weather to be good with visibility 10 miles, clouds at 3,000 feet scatted, and no reported icing. The pilot asked the passenger if she knew anyone in Pilot Point that she could stay with that night, and she responded no and stated that she preferred to return to Dillingham if the airplane could not make it to the destination. The pilot decided to take off and continue the flight toward the intended destination to "take a look," and if the weather deteriorated, he would return to Dillingham.

According to the pilot, the airplane departed PNP and continued southwest at 800 feet. About eight miles south of PNP, the wind screen started to accumulate ice, so he maneuvered the airplane back toward the north as planned. The passenger stated that after departing PNP, the visibility deteriorated, and the airplane was in clouds or fog after it turned around, and the engine did not sound right. The pilot stated that the aircraft began accumulating light structural ice and the engine started "running rough." He turned on the carburetor heat and engine performance was restored briefly. About 6 miles south of PNP at 500 feet, severe icing and visibility below 1 mile was encountered. The flight controls became sluggish, all the windows started icing over rapidly, and the engine surged with strong propeller vibrations. The airplane would not maintain altitude and descended through 400 feet. The pilot performed a forced landing on an easterly heading near the King Salmon River and Ugashik River confluence. During the landing sequence, the right main landing gear and the nose landing gear sheared off due to impact with ground ice. The fuselage, right wing, and right horizontal stabilizer sustained substantial damage. (Refer to figure 1.) The pilot and passenger sustained serious injuries during the impact and successfully egressed the airplane. Together they operated the Emergency Locator Transmitter, a mobile marine radio and the strobe light to effect rescue. The passenger, using her cell phone, called the Federal Aviation Administration Flight's Service Station in Dillingham to report the accident. A U.S. Coast Guard MH-60 helicopter extracted the survivors from the remote location about 1830.

The closest weather reporting facility is PNP, about 5 miles north of the accident site. At 1521, an aviation special weather report (SPECI) stated in part: wind from 140 degrees at 5 knots; sky condition, overcast at 1,600 feet; visibility 1 ¾ statute miles in light snow; temperature 7°F; dewpoint 1°F; barometric pressure 29.23 inches mercury.

A review of the Alaska Aviation Weather Unit graphic forecast charts indicated marginal VFR conditions along the route of flight with no significant icing or turbulence forecast. There were no published pilot reports (PIREPs) of icing conditions in the area. Also, the pilot stated that he obtained weather information form National Weather Service online services and determined no significant weather was forecast.

The pilot stated that there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.


Figure 1. N4261T PA-32-260 wreckage at the accident scene.

Pilot Information

Certificate: Airline Transport
Age: 54, Male
Airplane Rating(s): Multi-engine Land; Single-engine Land
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used:
Instrument Rating(s): Airplane
Second Pilot Present: No
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 2 With Waivers/Limitations
Last FAA Medical Exam: 04/18/2016
Occupational Pilot: Yes
Last Flight Review or Equivalent: 01/19/2016
Flight Time:  (Estimated) 12824 hours (Total, all aircraft), 9873 hours (Total, this make and model), 12778 hours (Pilot In Command, all aircraft), 67 hours (Last 90 days, all aircraft), 38 hours (Last 30 days, all aircraft), 2.5 hours (Last 24 hours, all aircraft)

Aircraft and Owner/Operator Information

Aircraft Make: PIPER
Registration: N4261T
Model/Series: PA-32 260
Aircraft Category: Airplane
Year of Manufacture: 1971
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: 32-7200013
Landing Gear Type: Tricycle
Seats: 6 
Date/Type of Last Inspection: 08/20/2016, Annual
Certified Max Gross Wt.: 3400 lbs
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time: 4120.1 Hours as of last inspection
Engine Manufacturer: LYCOMING
ELT: C91  installed, activated, aided in locating accident
Engine Model/Series: O-540-E4B5
Registered Owner: VANDEVENTER MATTHEW S
Rated Power: 260 hp
Operator: VAN AIR INC
Operating Certificate(s) Held: On-demand Air Taxi (135)
Operator Does Business As: Van Air
Operator Designator Code: V5DA

Meteorological Information and Flight Plan

Conditions at Accident Site: Instrument Conditions
Condition of Light: Day
Observation Facility, Elevation: PAPN, 56 ft msl
Distance from Accident Site: 5 Nautical Miles
Observation Time: 1521 AKS
Direction from Accident Site: 346°
Lowest Cloud Condition:
Visibility: 1.75 Miles
Lowest Ceiling: Overcast / 1600 ft agl
Visibility (RVR):
Wind Speed/Gusts: 5 knots /
Turbulence Type Forecast/Actual: 
Wind Direction: 140°
Turbulence Severity Forecast/Actual:
Altimeter Setting: 29.23 inches Hg
Temperature/Dew Point: -13°C / -16°C
Precipitation and Obscuration: No Obscuration
Departure Point: PILOT POINT, AK (PNP)
Type of Flight Plan Filed: VFR
Destination: PORT HEIDEN, AK (PTH)
Type of Clearance: None
Departure Time: 1505 AKS
Type of Airspace: Class G

Wreckage and Impact Information

Crew Injuries: 1 Serious
Aircraft Damage: Substantial
Passenger Injuries: 1 Serious
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 2 Serious
Latitude, Longitude: 57.495000, -157.540000 (est)

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