# NTSB CHI98LA154: Fokker F-28 MK100, N1400H, Ft. Wayne, IN, May 13, 1998 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: May 13, 1998, 08:39 local (12:39 UTC) - Place: Ft. Wayne, IN - Coordinates: 41.000892, -85.210861 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.0009&lon=-85.2109&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious, 38 uninjured - Status: Completed, report July 2, 1999 - Report: Approved by Office Director - NTSB case key (mKey): 10878 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI98LA154 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/10878/pdf - Page: https://openairdocs.org/ntsb/CHI98LA154 ## Probable cause In-flight encounter with turbulence. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Altitude deviation,uncontrolled, descent - weather condition - turbulence (cause) ## Analysis The #1 flight attendant suffered a fractured ankle when she got up from a passenger seat to answer the interphone during moderate turbulence. The captain reported they encountered moderate turbulence while deviating around a small cell. The seat belt sign was turned on at the time of the encounter. Two SIGMETs were in effect at the time which had outlooks covering the area of the encounter. Both of the outlooks were calling for diminishing thunderstorm activity in the area. ## Factual narrative On May 13, 1998, at 0839 eastern daylight time, a Fokker F-28 MK100, N1400H, operated by American Airlines as flight 1275 experienced moderate turbulence 20 miles east of Ft. Wayne, Indiana, during a descent through FL250. The #1 flight attendant received a fractured ankle. The captain, first officer, #2 flight attendant, and 35 passengers were not injured. The 14 CFR Part 121 flight was operating on an IFR flight plan. The airplane was not damaged. The flight originated from Washington, D.C., at 0710 eastern daylight time. The flight continued to Chicago, Illinois, where it landed uneventfully at 0803 central daylight time. The captain reported they were experiencing "light chop" while descending through FL250 at 250 knots. He reported they were deviating south around a small cell when moderate turbulence was encountered. The captain reported he called the flight attendants to tell them to take their seats. The #1 flight attendant answered the call stating that they were already sitting down. The captain stated that the #1 flight attendant then came into the cockpit and informed him that she had fallen and hurt herself during the turbulence encounter. The captain reported he instructed her to sit down and he coordinated with the #2 flight attendant for her to assume the duties of the #1 flight attendant for the remainder of the flight. The #1 flight attendant reported that the seatbelt sign had been turned on and she was completing her cabin check when it started getting "bumpy." She stated that she and the #2 flight attendant sat down in passenger seats near the back of the airplane. She stated the captain called back on the interphone using two rings. She stated that she and the #2 flight attendant remained seated until they heard the interphone ring a second time. The #1 flight attendant reported she got up to answer the call. She reported, "I ended up flying through the air and then landing on my knee, and elbow with my ankles going every which way. I then got up to the back jumpseat and realized I was pretty shaken up and my head and ankles were hurting." She reported she then informed the captain of the situation and that she needed medical attention. SIGMET 20C was issued at 0355 edt for Illinois and Indiana. The outlook for this SIGMET covered the area of the turbulence encounter and was valid from 0555 edt until 0955 edt. The outlook stated that thunderstorm activity was expected to slowly weaken during the period. A strong inflow of warm and moist air had ceased with a loss of the low level jetstream and the southerly air mass over the region had begun to gradually stabilize. The upper system providing dymanic support for convection was moving northeastward across the upper Great Lakes into Canada. SIGMET 1E was issued at 0555 edt for Indiana and Michigan. The outlook for this SIGMET covered the area of the turbulence encounter and was valid from 0755 edt until 1155 edt. The outlook stated that widely scattered thunderstorm activity was expected to continue to slowly weaken during the rest of the morning. Both of these SIGMETs were included in the dispatch weather information provided to the flightcrew of N1400H prior to the flight. ## Aircraft - Registration: [N1400H](https://openairdocs.org/deregistered/N1400H-2004-03-11), registration cancelled 2004-03-11, S/N 11340, built 1991 (OpenAirDocs) - Reported make and model: Fokker F-28 MK100 - Registry model: [Fokker F.28 MK 0100](https://openairdocs.org/model/fokker-f-28-mk-0100) (registry code 4990807) (OpenAirDocs) - Registry engine: [Rolls-Royce TAY-650-15](https://openairdocs.org/engine/rolls-royce-tay-650-15) (registry code 54557, turbo-fan) (OpenAirDocs) - Category: Airplane - Serial number: 11340 - Airframe hours: 14827 - Engines: Rolls-Royce TAY 650-1-5 15100 horsepower turbo fan - Damage: No damage - Flight: Part 121 - Registered owner: American Airlines, Inc. - Airworthiness certificate: Standard, Transport - Last inspection: Continuous airworthiness, April 30, 1998, 101 hours before - Departed: DCA, WASHINGTON, DC - Destination: ORD, CHICAGO, IL - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 49; flight engineer, airline transport, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 2,995 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 110° at 7 knots - Visibility: 4 statute miles - Lowest ceiling: 4,600 ft overcast - Temperature: 61 °F, dew point 57 °F - Altimeter: 29.00 inHg - Observed at: FTW ## 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 19980513046339A](https://openairdocs.org/incident/19980513046339A), May 13, 1998: Fokker F28MK0100, Ft. Wayne, IN. (.4)The #1 flight attendant suffered a fractured ankle when she got up from a passenger seat to answer the interphone during moderate turbulence. The captain… 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.