# NTSB IAD96IA048: Boeing 767-2B7, N656US, Pittsburgh, PA, February 20, 1996 - Type: NTSB incident investigation - Classification: Incident · Minor injuries · Incident investigation · Final report - Date: February 20, 1996, 17:30 local (22:30 UTC) - Place: Pittsburgh, PA - Location: 40.4406° N, 79.9959° W: Placed by OpenAirDocs: center of Pittsburgh, PA, within about 6 miles (OpenAirDocs) - Nearby events: https://openairdocs.org/map.md?lat=40.4406&lon=-79.9959&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 7 minor, 140 uninjured - Status: Completed, report February 28, 1997 - Report: Approved by Office Director - NTSB case key (mKey): 28020 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=IAD96IA048 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/28020/pdf - Page: https://openairdocs.org/ntsb/IAD96IA048 ## Probable cause the in-flight encounter with unforecast turbulence. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, approach - weather condition - turbulence (cause) ## Analysis The airplane was approaching the destination at 10,000 feet msl in a thin cloud layer, when it encountered moderate turbulence. The flight continued, and landed at the destination airport without further incident. The flightcrew reported that the seatbelt sign was illuminated and the arrival PA announcement had been made, when the turbulence encounter occurred. The turbulence was unforecast. ## Factual narrative HISTORY OF FLIGHT On February 20, 1996, at 1730 eastern standard time, a Boeing B767-2B7, N656US, operated as a scheduled domestic passenger flight by USAir, Inc., encountered moderate turbulence while in cruise flight at 10,000 feet mean sea level (msl), during the approach for landing at the Pittsburgh International Airport (KPIT), Pittsburgh, Pennsylvania. Of the 139 passengers and 8 crew members on board the airplane, six flight attendants and one passenger received minor injuries. The airplane was not damaged. The flight was operating on an IFR flight plan at the time of the turbulence encounter. The flight operated under 14 CFR Part 121, and originated from Boston, Massachusetts, at about 1605. The captain stated that the airplane was in level flight at 10,000 feet msl, in a thin cloud layer about 30 miles northeast of the destination airport, operating at an indicated airspeed of 290 knots, when the flight encountered approximately six seconds of moderate turbulence. He said the seatbelt sign was illuminated, and the routine arrival public address (PA) announcement had been performed. He said that before and after the unforecast turbulence encounter, the flight had been smooth, and all operations were normal. The six flight attendants were performing arrival duties when the turbulence encounter occurred, and they received minor injuries. One passenger, who was in the aft lavatory, also received minor injuries. Upon arrival at Pittsburgh, paramedics met the flight and the injured persons were taken to the Ohio Valley Hospital, treated, and released. (Flight attendant statements are appended.) The flight attendants stated that they were all standing in various areas of the aircraft preparing for landing when the turbulence encounter occurred. They said that, although the seatbelt sign was on, one passenger had disregarded the sign and had gone to the aft lavatory. The flight attendants reported that the first jolt of turbulence got their attention, then moments later they were in the air. They indicated that they bumped their heads on the ceiling/overhead bins, then landed on the floor. The flight attendants indicated that, after they recovered, they made inquired to see if any of the passengers were injured. The flight attendants then secured themselves in their jumpseats until the airplane had safely landed. ADDITIONAL INFORMATION One flight attendant was initially diagnosed with a serious "Nondisplaced T6 vertebral body fracture," however, subsequent reviews of the X-rays by medical experts revealed that the T6 fracture could not be confirmed. (Medical evaluations are appended.) ## Aircraft - Registration: N656US (not matched to a registry record) - Reported make and model: Boeing 767-2B7 - Category: Airplane - Serial number: 26847 - Engines: turbo fan - Damage: No damage - Flight: Part 121 - Registered owner: Usair - Airworthiness certificate: Standard, Transport - Departed: BOS, BOSTON, MA - Destination: PIT - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 57; airline transport; airplane ratings: multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 24,115 total, 1,567 in this make and model, 186 in the last 90 days ## Weather - Conditions: Visual (VMC), Dusk - Wind: 100° at 6 knots - Visibility: 1 statute miles - Lowest ceiling: 1,600 ft overcast - Temperature: 45 °F, dew point 43 °F - Altimeter: 29.00 inHg - Observed at: PIT ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Incident 19960220004669I](https://openairdocs.org/incident/19960220004669I), Feb 20, 1996: Boeing 7672B7, Pittsburgh, PA. Narrative: aircraft inbound to Pittsburgh, PA and had just leveled off at 10,000 ft. when the aircraft experienced three quick jolts lasting approximately six… From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.