Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
New Market, West Virginia 22853
Wednesday, November 18, 2009 19:30 EST
NTSB Narrative Summary Released at Completion of Accident
Prior to and after the turbulence encounter the captain reported smooth air while level at FL310. There were no reported sigmets, airmets, or pilot reports issued, nor were there “watch boxes” that warned of adverse weather. The onboard weather radar was functioning when suddenly the airplane went through a cloud at Mach 0.84 and encountered moderate turbulence for about 10 to 15 seconds. He said that there was an overspeed warning alarm and he immediately took over manual control of the airplane maintaining control, and activated the seat belt warning sign which had previously been off, since the flight had been smooth. The first officer statement was consistent with the captain’s and in addition he reported seeing “considerable St. Elmo’s Fire” throughout the duration of the turbulence.
The aircraft’s flight data recorder indicated that while the aircraft was level at FL310, the vertical acceleration changed from 1.25 g’s to -0.5 g’s in less than one second and then abruptly reached 2.0 g’s within a few seconds before reducing to minor oscillations that were between 1.25 g’s and 0.75 g’s which lasted for about 15 seconds. According to the FDR data, the turbulence lasted about 20 seconds.
The NTSB conducted a meteorological study to assess weather conditions in the area where the flight encountered turbulence, and the National Weather Service’s Radar Summary for 1918 EST depicted an extensive area of rain showers over the region with a few radar echo tops between 31,000 feet and 48,000 feet. In addition, the regional radar composite imagery showed that between 1910 and 1940 EST there was a small area of reflectivity between 5 and 25 decibels in the area of the turbulence encounter.
NTSB Probable Cause Narrative
The flight crew’s inadvertent encounter with a small area of cumulous clouds at night that resulted in moderate to severe convectively induced turbulence.
Event Information
| Type of Event | Accident |
| Event Date | 11/18/2009 |
| Event Day of the Week | Wednesday |
| Time of Event | 1930 |
| Event Time Zone | Eastern Standard Time |
| Event City | New Market |
| Event State | WEST VIRGINIA |
| Event Country | -- |
| Zipcode of the event site | 22853 |
| Event Date Year | 2009 |
| Event Date Month | 11 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 383920N |
| Event Location Longitude | 0784229W |
| Event Location Airport | -- |
| Event Location Nearest Airport ID | -- |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | -- |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Unknown |
| Time of the weather observation | |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | -- |
| Elevation of weather observation facility | -- |
| Distance of event from weather observation facility (units?) | -- |
| Time Zone of the weather observation | -- |
| Lighting Conditions | Night |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | -- |
| Sky/Lowest/Cloud Conditions | -- |
| Sky Condition for Lowest Ceiling | -- |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | -- |
| Air Temperature at event time (in degrees celsius) | -- |
| Dew Point at event time (in degress fahrenheit) | -- |
| Wind Direction (degrees magnetic) | -- |
| Variable Wind Indicator | -- |
| Wind Speed (knots) | -- |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | -- |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | -- |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | Serious |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | -- |
| Injury Total Minor | 1 |
| Injury Total None | 198 |
| Injury Total Serious | 1 |
| Injury Total All | 2 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | -- |
| NTSB Notification Source | UAL Manager of Flight Safety |
| NTSB Notification Date | -- |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | Dec 27 2011 4:44PM |
| User who most recently changed record | schd |
| Basic weather conditions | Instrument Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N209UA |
| NTSB Number | DCA10FA012 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 121: Air Carrier |
| Type of Flight Plan filed | IFR |
| Flight plan Was Activated? | Yes |
| Damage | None |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | BOEING |
| Aircraft Model | 777-200 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 30215 |
| Certified Max Gross Weight | 640000 |
| Aircraft Category | Airplane |
| Aircraft Registration Class | -- |
| Aircraft is a homebuilt? | No |
| Flight Crew Seats | 2 |
| Cabin Crew Seats | 8 |
| Passenger Seats | 190 |
| Total number of seats on the aircraft | 200 |
| Number of Engines | 2 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | Continuous Airworthiness |
| Date of Last Inspection | Nov 9 2008 12:00AM |
| Airframe hours since last inspection | -- |
| Airframe Hours | 41788 |
| ELT Installed | Unknown |
| ELT Activated | Unknown |
| ELT Aided Location of Event Site | Unknown |
| 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 | United Airlines Inc., |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | 1200 E. Algonquin Road |
| Operator City | Elk Grove Village |
| Operator State | IL |
| Operator Country | USA |
| Operator Zip code | 60007 |
| 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 | Domestic |
| 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 | ORD |
| Departure City | Chicago |
| Departure State | IL |
| Departure Country | USA |
| Departure Time | 1819 |
| Departure Time Zone | CST |
| Destination Same as Local Flt | -- |
| Destination Airport Code | IAD |
| Destination City | Sterling |
| Destination State | VA |
| Destination Country | USA |
| Specific Phase of Flight | -- |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | May 24 2011 6:28PM |
| User who most recently changed record | lovj |
| Since inspection or accident | Last Inspection |
| Event Location Runway Number and Location | N/A |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |