Individually Owned: 150,657
Corporate Owned: 137,281
Chicago O'hare Intl Airport
Aircraft Accident/Incident Report
Chicago, Illinois 60018
Friday, December 14, 2007 15:55 CST
NTSB Narrative Summary Released at Completion of Accident
On approach for landing, about 13 miles from the airport, the flight crew was informed that the cabin was filling with smoke. The cabin crew was unable to determine the source of the smoke. The captain declared an emergency in order to get the airplane on the ground as soon as possible. The first officer performed a normal landing and turned off on the first high-speed taxiway, at which time he noticed a low oil indication on the right engine. The engine was subsequently shut down. The captain elected to initiate an emergency evacuation due to the uncertainty of the situation and the possibility of a fire on-board. During the evacuation, one passenger sustained a fracture of a vertebra. Post accident examinations revealed a low oil quantity in the right engine, with metallic deposits on one of the engine chip detectors. A detailed teardown inspection of the right engine revealed the #2 bearing had failed. The compressor gas path exhibited oil deposits consistent with oil migration into the airplane's environmental system. The cabin pressurization system utilized 8th and 15th stage engine compressor bleed air. No evidence of an engine or cabin fire was observed. The engine manufacturer had released an improved bearing design prior to the accident. At that time, the operator began replacing the bearings on an attrition basis when the original bearings were no longer serviceable. However, the operator has revised that policy and is proactively replacing the original bearings, regardless of the condition, with the improved bearings.
NTSB Probable Cause Narrative
Emergency evacuation due to dense smoke in the cabin and the possibility of an on-board fire, which resulted in a serious injury to one of the 264 passengers and crew. An additional cause was the failure of an engine bearing, allowing oil to migrate into the environmental system, and resulted in the smoke in the cabin.
Event Information
| Type of Event | Accident |
| Event Date | 12/14/2007 |
| Event Day of the Week | Friday |
| Time of Event | 1555 |
| Event Time Zone | Central Standard Time |
| Event City | Chicago |
| Event State | ILLINOIS |
| Event Country | -- |
| Zipcode of the event site | 60018 |
| Event Date Year | 2007 |
| Event Date Month | 12 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 415843N |
| Event Location Longitude | 0875417W |
| Event Location Airport | Chicago O'Hare Intl |
| Event Location Nearest Airport ID | ORD |
| Indicates whether the acc/inc occurred off or on an airport | On Airport |
| Distance from airport in statute miles | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | 668 |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1551 Central Daylight Time |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | ORD |
| Elevation of weather observation facility | 668 |
| Distance of event from weather observation facility (units?) | -- |
| Time Zone of the weather observation | CDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 2200 |
| Lowest Non-Ceiling Height | -- |
| Sky/Lowest/Cloud Conditions | -- |
| Sky Condition for Lowest Ceiling | Broken |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | -4 |
| Dew Point at event time (in degress fahrenheit) | -9 |
| Wind Direction (degrees magnetic) | -- |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 4 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.4 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | METAR KORD 142151Z VRB04KT 10SM BKN022 BKN250 M04/ |
| Event Highest Injury | Serious |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | -- |
| Injury Total Minor | -- |
| Injury Total None | 263 |
| Injury Total Serious | 1 |
| Injury Total All | 1 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 24429 |
| NTSB Notification Source | FAA |
| NTSB Notification Date | Dec 14 2007 12:00AM |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | Oct 10 2008 3:44PM |
| User who most recently changed record | sort |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | FAA-O'Hare FSDO |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N220UA |
| NTSB Number | CHI08FA050 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 121: Air Carrier |
| Type of Flight Plan filed | IFR |
| Flight plan Was Activated? | Yes |
| Damage | Minor |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Boeing |
| Aircraft Model | 777-222 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 30222 |
| Certified Max Gross Weight | 640000 |
| Aircraft Category | Airplane |
| Aircraft Registration Class | -- |
| Aircraft is a homebuilt? | No |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | 270 |
| Number of Engines | 2 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | Continuous Airworthiness |
| Date of Last Inspection | Aug 1 2007 12:00AM |
| Airframe hours since last inspection | -- |
| Airframe Hours | 26287 |
| ELT Installed | -- |
| ELT Activated | -- |
| ELT Aided Location of Event Site | -- |
| ELT Type | -- |
| Aircraft Owner Name | United Airlines Inc |
| Aircraft Owner Street Address | 1200 E Algonquin Road |
| Aircraft Owner City | Elk Grove Village |
| Aircraft Owner State | IL |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 60007 |
| Operator is an individual? | No |
| Operator Name | -- |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | -- |
| Operator City | -- |
| Operator State | -- |
| Operator Country | USA |
| Operator Zip code | -- |
| Operator Code | UALA |
| Owner has at least one certificate | Yes - certificate holder |
| Other Operator of large aircraft? | No |
| Certified for Part 133 or 137 Operation | -- |
| Operator Certificate Number | -- |
| Indicates whether an air carrier operation was scheduled or not | Scheduled |
| Indicates Domestic or International Flight | International |
| Operator carrying Pax/Cargo/Mail | Passenger Only |
| Type of Flying (Per_Bus / Primary) | -- |
| Second Pilot on Board | Yes |
| Departure Point Same as Event | No |
| Departure Airport Code | PVG |
| Departure City | Shanghai |
| Departure State | -- |
| Departure Country | CH |
| Departure Time | 900 |
| Departure Time Zone | UTC |
| Destination Same as Local Flt | crash at destination city |
| Destination Airport Code | ORD |
| Destination City | Chicago |
| Destination State | IL |
| Destination Country | USA |
| Specific Phase of Flight | Approach |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Oct 10 2008 3:44PM |
| User who most recently changed record | sort |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | 10 |
| Runway Length | 10144 |
| Runway Width | 150 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |