Sunday, August 26, 2018

Swearingen SA226TC, registered to and operated by Western Airlines, N158WA: Accident occurred March 20, 2017 at Boise Air Terminal/Gowen Field (KBOI), Ada County, Idaho

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

Additional Participating Entity:

Federal Aviation Administration / Flight Standards District Office; Boise, Idaho

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/N158WA  


Location: Boise, ID
Accident Number: WPR17LA078
Date & Time: 03/20/2017, 0405 MDT
Registration: N158WA
Aircraft: SWEARINGEN SA226
Aircraft Damage: Substantial
Defining Event: Part(s) separation from AC
Injuries: 1 None
Flight Conducted Under: Part 91: General Aviation - Positioning 

On March 20, 2017, about 0405 mountain daylight time, a Swearingen SA226TC, N158WA, was substantially damaged due to foreign object damage to the airplane's fuselage during initial takeoff/climb from Boise Air Terminal/Gowen Field (BOI), Boise, Idaho. The airline transport pilot was not injured. The airplane was registered to and operated by Western Airlines LC of Boise as a 14 Code of Federal Regulations Part 91 positioning flight. Visual meteorological conditions prevailed at the time, and an instrument flight rules flight plan was filed and active. The flight was originating at the time and destined for Salt Lake International Airport (SLC), Salt Lake City, Utah.

In a written statement submitted to the National Transportation Safety Board investigator-in-charge, the pilot reported that prior to departing on the repositioning flight, he reviewed the maintenance data for the airplane (the Can) and found everything to be up to date. The subsequent preflight inspections, inclusive of the interior and exterior of the airplane revealed no anomalies. The pilot stated that at 0400 he called BOI ground control, obtained taxi clearance, and taxied to runway 10L where he began the takeoff roll. The pilot reported that everything was normal, rotated at 105 knots; shortly thereafter he heard a "pop", followed by a vibration. Thinking that he had a blown tire, he waited a few seconds to see if the frequency of the vibration would change as the tire rotation slowed. However, the vibration remained the same, which led him to think that there might be an issue with the propeller. The pilot radioed the BOI tower controller, advised him of his intension to return to the airport, and was instructed to turn right for Runway 10L. The pilot stated that on the downwind leg he thought there might be a problem with a propeller. However, after he inspected both propeller spinners to determine which propeller might be damaged, he determined that both were running smooth. The pilot further stated that as he had no indication as to which propeller was damaged and the vibration was light and not changing, he elected not to shut the engine down. The pilot then landed uneventfully, taxied to parking, and shut the right engine down first. The pilot then shut the left engine down. During the last few rotations of the propeller he observed the spinner wobble slightly; he then noticed that the tip of one of the blades was missing. The pilot stated that after having exited the airplane he observed that about four inches of one of the propeller blade tips was missing, as well as having observed two holes in the fuselage, [both caused by pieces of the propeller blade tip]. About 10 minutes later airport operations personnel delivered another piece of the propeller [blade], and what appeared to be the blade of a screwdriver and two pieces of a screwdriver handle. A further examination of the airplane revealed a third hole in the fuselage further back [of the left] wing root just below the window.

During a postaccident inspection of the airplane, a Federal Aviation Administration aviation safety inspector reported that maintenance had been performed on the airplane prior to the flight, and that the mechanic was called away from the task he was performing prior to it being completed. The inspector stated that a screwdriver was left on the nose of the airplane under the windshield wiper and out of sight of the pilot. Subsequently, on takeoff roll the screwdriver became dislodged and impacted the left propeller; remnants of two pieces of a propeller blade were found to have penetrated the left side fuselage and came to rest inside the cabin of the airplane. The screwdriver was subsequently located lying on the surface of the departure runway.

Pilot Information

Certificate: Airline Transport
Age: 62, Male
Airplane Rating(s): Multi-engine Land; Single-engine Land
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used: 4-point
Instrument Rating(s): Airplane
Second Pilot Present: No
Instructor Rating(s): Airplane Multi-engine; Airplane Single-engine
Toxicology Performed: No
Medical Certification: Class 2 Unknown
Last FAA Medical Exam: 10/31/2016
Occupational Pilot: Yes
Last Flight Review or Equivalent: 01/31/2017
Flight Time: 10700 hours (Total, all aircraft), 3161 hours (Total, this make and model), 7919 hours (Pilot In Command, all aircraft), 37 hours (Last 90 days, all aircraft), 31 hours (Last 30 days, all aircraft) 

Aircraft and Owner/Operator Information

Aircraft Make: SWEARINGEN
Registration: N158WA
Model/Series: SA226 TC
Aircraft Category: Airplane
Year of Manufacture: 1981
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: TC411
Landing Gear Type: Retractable - Tricycle
Seats: 3
Date/Type of Last Inspection: 03/04/2017, AAIP
Certified Max Gross Wt.: 13230 lbs
Time Since Last Inspection: 182 Hours
Engines: 2 Turbo Prop
Airframe Total Time: 28602.9 Hours as of last inspection
Engine Manufacturer: Honeywell
ELT: C126 installed, not activated
Engine Model/Series: TPE-331-10UA
Registered Owner: Western Airlines LC
Rated Power: 940 hp
Operator: On file
Operating Certificate(s) Held: Commuter Air Carrier (135) 

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Night/Dark
Observation Facility, Elevation: BOI, 2871 ft msl
Distance from Accident Site:
Observation Time: 0353 MDT
Direction from Accident Site:
Lowest Cloud Condition: Few / 6500 ft agl
Visibility:  10 Miles
Lowest Ceiling: Overcast / 12000 ft agl
Visibility (RVR):
Wind Speed/Gusts: 7 knots /
Turbulence Type Forecast/Actual: / None
Wind Direction: 170°
Turbulence Severity Forecast/Actual: /
Altimeter Setting: 30.06 inches Hg
Temperature/Dew Point: 9°C / 7°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Boise, ID (BOI)
Type of Flight Plan Filed: IFR
Destination: Denver, CO (KAPA)
Type of Clearance: IFR
Departure Time: 0405 MDT
Type of Airspace: Class C 

Airport Information

Airport: Boise Air Terminal/Gowen Field (BOI)
Runway Surface Type: Asphalt
Airport Elevation: 2871 ft
Runway Surface Condition: Wet
Runway Used: 10L
IFR Approach: None
Runway Length/Width: 10000 ft / 150 ft
VFR Approach/Landing: Traffic Pattern

Wreckage and Impact Information

Crew Injuries: 1 None
Aircraft Damage: Substantial
Passenger Injuries: N/A
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 None
Latitude, Longitude:  43.614444, -116.222778

NTSB Identification: WPR17LA078
Nonscheduled 14 CFR Part 135: Air Taxi & Commuter
Accident occurred Monday, March 20, 2017 in Boise, ID
Aircraft: SWEARINGEN SA226, registration: N158WA
Injuries: 1 Uninjured.

This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed. NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

On March 20, 2017, about 0400 mountain daylight time, a Swearingen SA226TC, N158WA, was substantially damaged due to foreign object damage to the airplane's propeller and fuselage during initial takeoff/climb from Boise Air Terminal/Gowen Field (BOI), Boise, Idaho. The airline transport pilot, who was the sole occupant, was not injured. The airplane was registered to and operated by Western Airlines LC of Boise. Visual meteorological conditions prevailed at the time of the accident, and an instrument flight rules flight plan was filed, but not activated. The charter cargo flight was being operated in accordance with 14 Code of Federal Regulations Part 135, with a destination of Centinnial Airport (APA), Denver, Colorado.

According to Federal Aviation Administration personnel, about the time the airplane was rotating from Runway 10L, the pilot experienced a light vibration; he subsequently returned to BOI and landed uneventfully. During a post-landing examination of the airplane, it was revealed that a portion of the outboard section of a left propeller blade, which had fragmented into 2 pieces, was missing. Additionally, about a 4 inch by 4 inch puncture hole was observed to have gone through the left forward side of the fuselage just aft of the main air stair door; a piece of the propeller blade was found in the cabin. It was further noted during a runway sweep for foreign objects shortly after the occurrence, that a screw driver which had been used during maintenance on the airplane earlier, and the second piece of the propeller blade tip, were both recovered from the departure runway in the same approximate location from where the airplane would have rotated.

1 comment:

Anonymous said...

OMG. 4 dollar screwdriver causes thousands in damage! Can't make this stuff up!