# NTSB CHI96IA145: Boeing 727-222A, N7443U, Chicago, IL, April 28, 1996 - Type: NTSB incident investigation - Classification: Incident · Minor injuries · Incident investigation · Final report - Date: April 28, 1996, 15:00 local (20:00 UTC) - Place: Chicago, IL - Location: 41.8500° N, 87.6501° W: Placed by OpenAirDocs: center of Chicago, IL, within about 9 miles (OpenAirDocs) - Nearby events: https://openairdocs.org/map.md?lat=41.8500&lon=-87.6501&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor, 135 uninjured - Status: Completed, report July 11, 1996 - Report: Approved by Office Director - NTSB case key (mKey): 10118 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI96IA145 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/10118/pdf - Page: https://openairdocs.org/ntsb/CHI96IA145 ## Probable cause a passenger disturbance that required the flight attendant to leave her seat. A factor in this accident was the encounter with turbulence as the flight attendant was performing her assigned duties. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, descent - weather condition - turbulence (contributing factor) - passenger briefing - performed, flightcrew - disturbance, passenger (cause) ## Analysis The airline flight was at Flight Level 240 when the ARTCC advised the captain of possible moderate chop starting at Flight Level 220. The captain advised the flight attendants of this information. A few minutes later the flight was instructed to descend to Flight Level 190. The captain turned on the seat belt sign and requested that the passengers take their seats. During the descent the flight encountered turbulence as it entered a cloud layer at Flight Level 220. As the flight entered the cloud layer a flight attendant was dealing with a passenger who had gotten out of their seat. The flight attendant fell against the passenger seat arm and onto the floor during the turbulence encounter. ## Factual narrative On April 28, 1996, at 1500 central daylight time, a Boeing 727- 222A, N7443U, operated by United Airlines, Incorporated, of Chicago, Illinois, as Flight Number 392, and piloted by an airline transport and commercially certificated crew, encountered moderate turbulence during a descent into Chicago, Illinois. The 14 CFR Part 121 flight was operating on a IFR flight plan. Instrument meteorological conditions prevailed at the time of the accident. The 3 person flight crew, 3 flight attendants, and 129 passengers were not injured. A fourth flight attendant received minor injuries. The flight departed San Jose, California, at 1004 pacific daylight time. The flight was at Flight Level 240 when the Federal Aviation Administration's Chicago Air Route Traffic Control Center controller (controller) advised the flight's captain of possible moderate chop starting at Flight Level 220. The captain said he advised the flight attendants that they had a couple of minutes to finish closing the galleys and take a seat. About 2 to 3 minutes later, the controller instructed Flight 392 to descend to Flight Level 190. The captain turned the seatblt sign on and requested the pasengers take their seats. During the descent the flight encountered turbulence as it entered a cloud layer at Flight Level 220. A flight attendant was dealing with a passenger who had gotten out of their seat. The flight attendant fell against the passenger's seat arm and then onto the floor during the turbulence encounter. The airline reported that the flight attendant suffered a severly sprained back. The injured flight attendant was assigned seat number 1, left, outboard. ## Aircraft - Registration: [N7443U](https://openairdocs.org/deregistered/N7443U-2006-06-28), registration cancelled 2006-06-28, S/N 21897, built 1979 (OpenAirDocs) - Reported make and model: Boeing 727-222A - Registry model: [Boeing 727-222](https://openairdocs.org/model/boeing-727-222) (registry code 1384073) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Airplane - Serial number: 21897 - Airframe hours: 45716 - Engines: P&W JT8D-15 15500 lbs thrust turbo jet - Damage: No damage - Flight: Part 121 - Registered owner: United Airlines, Inc. - Airworthiness certificate: Standard, Transport - Last inspection: Continuous airworthiness, June 8, 1995, 2,557 hours before - Departed: SJC, SAN JOSE, CA - Destination: ORD - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 47; flight engineer, airline transport, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 12,071 total, 4,957 in this make and model, 8,863 as pilot in command, 166 in the last 90 days, 71 in the last 30 days, 11 in the last 24 hours ## Weather - Conditions: Instrument (IMC), Day - Wind: 70° at 9 knots - Visibility: 10 statute miles - Lowest ceiling: 5,500 ft overcast - Temperature: 50 °F, dew point 30 °F - Altimeter: 30.00 inHg - Observed at: ORD ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19960428014539A](https://openairdocs.org/incident/19960428014539A), Apr 28, 1996: Boeing 727222, Chicago, IL. Encountered known turbulence on descent for airport. Flight attendant thrown to floor broke tailbone. Seat light on (-23) during a descent into Chicago o'Hare… 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.