Thursday, May 31, 2018

Southwest Airlines, Boeing 737-700, N758SW: Accident occurred August 14, 2014 at Salt Lake City International Airport (KSLC), Utah

Aviation Accident Factual Report - National Transportation Safety Board:

Investigation Docket - National Transportation Safety Board:

Location: Salt Lake City, UT
Accident Number: WPR14LA346
Date & Time: 08/14/2014, 0941 MDT
Registration: N758SW
Aircraft: BOEING 737 7H4
Aircraft Damage: Substantial
Defining Event: Ground handling event
Injuries: 5 None
Flight Conducted Under: Part 121: Air Carrier - Scheduled 

On August 14, 2014, about 0941 mountain daylight time, a Boeing 737-700 airplane, N758SW, was struck by a runaway baggage cart while sitting at the boarding gate, at the Salt Lake City International Airport (KSLC), Salt Lake City, Utah. The two airline transport pilots and three cabin crewmembers were not injured. The fuselage was substantially damaged. The airplane was registered to, and operated by, the Southwest Airlines Company, Dallas, Texas, as Southwest Flight 579, as a Title 14 Code of Federal Regulations Part 121 domestic passenger flight. An instrument flight rules flight plan was filed. The airplane was being prepared to board passengers when the event occurred.

During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on August 14, a representative of the Southwest Airlines Company said that he had been advised of the event in Salt Lake City, and received photographs showing structural damage to the airplane. He said the baggage cart had been on the end of a string of carts being pulled by a tug belonging to Delta Airlines. The cart came loose while being towed and rolled into the airplane, penetrating the side of the fuselage.

During a subsequent telephone conversation, a representative of Delta Airlines reported that a tug, belonging to Delta Airlines, had been pulling several baggage carts in the non-movement area adjacent to the airplane boarding gates. She said an airport surveillance video showed the second cart in the string hit a pothole and detached from the preceding cart. The loose baggage carts rolled across the ramp and into the side of the airplane.

Prior to the accident, there were no reported mechanical anomalies with the airplane.

According to a Salt Lake City Airport Police report, the Delta Employee who drove the event tug stated he was pulling a string of four baggage carts behind his tug, northbound on the airfield road on the east side of the Bravo Concourse. He said he was coming from Gate B-3 heading north to the baggage cart boneyard. He further reported that when he arrived at the boneyard, there was only 1 baggage cart attached to the tug. He did not know when or where the 3 missing carts had detached from the string.

A Southwest employee reported to the police that he was pulled up to the rear-belt loader on gate B-17. He detached 2 baggage carts from his tug and got back in his tug. He looked up and saw 3 Delta baggage carts rolling towards the belt-loader. He yelled to his fellow-employee to watch out, and the baggage carts swerved at the last second and collided with the airplane.

The second Southwest employee reported that he was standing by the belt-loader with his back to the airplane when he heard someone scream, "Lookout!!" He turned around just as the carts impacted the airplane. He reported that the carts impacted the airplane so hard the rear carts spun around.

The police report went on to report that security video recordings were obtained and showed that in the areas of Gates B-13 and B-15, the Delta Employee could be seen driving the tug out of his traffic lane veering to his left into the south bound traffic lane. The Employee reported that, that was done to avoid an airplane taxiing away from Gate B-15.

The report continued that, while traveling north in the southbound lane, the Delta Employee drove over a drain cover east of Gate B-15. When the baggage carts passed over the drain cover, the second baggage cart disconnected from the first baggage cart.

According to a Delta representative, after being notified of the event, Delta inspected the tug and baggage carts involved. They reported that all connection parts (tongues and springs) were found to be in good condition. Delta also reported that an additional video showed the tug maneuvering in a gate area for an extended period of time with the same carts attached. Delta reported that the tug driver stated he was confident the carts were properly connected.

Previous Events

During the airlines' investigations, employees at both Southwest and Delta reported knowing about the dip in the driving lane at the drain cover near Gate B15. Employees stated other similar disconnection events had occurred, but since the events did not result in damage or injury, documentation could not be located or did not exist.

The Southwest station manager reported that in November of 2013 an event occurred at the same spot in which a baggage cart disconnected from a tug. He stated the event was brought to the attention of airport authorities who stated the surface could not be leveled at that time because of the winter weather. The Station Manager further stated no action has been taken by the airport since that time. 

Pilot Information

Certificate: Airline Transport
Age: 44, Male
Airplane Rating(s): Multi-engine Land; Single-engine Land; Single-engine Sea
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used: 4-point
Instrument Rating(s): Airplane
Second Pilot Present: Yes
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 1 Without Waivers/Limitations
Last FAA Medical Exam: 08/15/2014
Occupational Pilot: Yes
Last Flight Review or Equivalent:
Flight Time:  15500 hours (Total, all aircraft), 9500 hours (Total, this make and model) 

Aircraft and Owner/Operator Information

Aircraft Manufacturer: BOEING
Registration: N758SW
Model/Series: 737 7H4 7H4
Aircraft Category: Airplane
Year of Manufacture: 1999
Amateur Built: No
Airworthiness Certificate: Normal; Transport
Serial Number: 27873
Landing Gear Type: Tricycle
Seats: 151
Date/Type of Last Inspection: 08/06/2014, Condition
Certified Max Gross Wt.: 154500 lbs
Time Since Last Inspection:
Engines: 2 Turbo Fan
Airframe Total Time: 53349 Hours
Engine Manufacturer: CFM INTL.
ELT: C126 installed, not activated
Engine Model/Series: CFM56 SERIES
Rated Power: 24200 lbs
Operating Certificate(s) Held: Flag carrier (121) 

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation:
Observation Time:
Distance from Accident Site:
Direction from Accident Site:
Lowest Cloud Condition: Few / 6000 ft agl
Temperature/Dew Point: 22°C / 15°C
Lowest Ceiling: None
Visibility:  10 Miles
Wind Speed/Gusts, Direction: 5 knots, 140°
Visibility (RVR):
Altimeter Setting: 30.08 inches Hg
Visibility (RVV):
Precipitation and Obscuration:
Departure Point:
Type of Flight Plan Filed: None
Type of Clearance: None
Departure Time:
Type of Airspace:

Airport Information

Runway Surface Type: N/A
Airport Elevation: 4227 ft
Runway Surface Condition:
Runway Used: N/A
IFR Approach: None
Runway Length/Width:
VFR Approach/Landing: None

Wreckage and Impact Information

Crew Injuries: 5 None
Aircraft Damage: Substantial
Passenger Injuries: N/A
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 5 None
Latitude, Longitude:  40.786389, -111.973056

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