# NTSB DCA11CA116: Boeing 737 7H4, N936WN, Cape Coral, FL, September 6, 2011 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Data collection · Final report - Date: September 6, 2011, 12:09 local (17:09 UTC) - Place: Cape Coral, FL - Coordinates: 26.44, -82.050003 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=26.4400&lon=-82.0500&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-descent: Turbulence encounter](https://openairdocs.org/ntsb-events/360) - Highest injury: Serious injuries - Injuries: 1 serious, 141 uninjured - Status: Completed, report February 23, 2017 - Report: Approved by Office Director - NTSB office: Major Investigations Division - NTSB case key (mKey): 82964 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DCA11CA116 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/82964/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=82964 - Page: https://openairdocs.org/ntsb/DCA11CA116 ## Probable cause An encounter with convective turbulence during the descent. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Turbulence: convective turbulence](https://openairdocs.org/ntsb-findings/03032020): Environmental issues › Conditions/weather/phenomena · Effect on personnel (probable cause); cases with it: [Boeing 737-7H4, 8 cases](https://openairdocs.org/ntsb-findings/03032020/cases.md?model=1384404), [All aircraft, 145 cases](https://openairdocs.org/ntsb-findings/03032020/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-descent: Turbulence encounter](https://openairdocs.org/ntsb-events/360) (defining event); cases with it: [Boeing 737-7H4, 16 cases](https://openairdocs.org/ntsb-events/360/sequence.md?model=1384404), [All aircraft, 423 cases](https://openairdocs.org/ntsb-events/360/sequence.md) ## Analysis On September 6, 2011, at about 1209 EDT, Southwest Airlines flight 983, a B737-700, N936WN, encountered turbulence enroute from Chicago Midway International Airport (MDW), Chicago, Illinois, to Fort Lauderdale-Hollywood International Airport (FLL), Fort Lauderdale, Florida. Of the five crew members and 137 passengers on board, one flight attendant received seriously injuries. The airplane was not damaged. According to flight crew statements, air traffic control informed them to expect turbulence from thunderstorms in mid to south Florida. In preparation for the possibility of turbulence, the captain called the flight attendants (FA) and advised them to close the galleys and to be seated and that they would likely be able to complete the cabin cleanup after clearing the weather at 10,000 feet. The flight deviated west of the weather and mostly smooth conditions were experienced for about 20 minutes during the descent. As the flight descended below about 14,000 feet, the flight momentarily encountered "large bumps" and two FAs were thrown to the floor after having just gotten out of their jump seats to finish cleaning up the aft galley. As a result, one FA experienced severe pain in her leg and was unable to complete her duties for the remainder of the flight. The captain was immediately informed of the injured FAs condition and medical assistance was requested to meet the airplane at the gate. After an uneventful landing, the FA was transported to the hospital and diagnosed with a broken leg. ## Factual narrative On September 6, 2011, at about 1209 EDT, Southwest Airlines flight 983, a B737-700, N936WN, encountered turbulence enroute from Chicago Midway International Airport (MDW), Chicago, Illinois, to Fort Lauderdale-Hollywood International Airport (FLL), Fort Lauderdale, Florida. Of the five crew members and 137 passengers on board, one flight attendant received serious injuries. The airplane was not damaged. According to flight crew statements, air traffic control informed them to expect turbulence from thunderstorms in mid to south Florida. In preparation for the possibility of turbulence, the captain called the flight attendants (FA) and advised them to close the galleys and to be seated and that they would likely be able to complete the cabin cleanup after clearing the weather at 10,000 feet. The flight deviated west of the weather and mostly smooth conditions were experienced for about 20 minutes during the descent. As the flight descended below about 14,000 feet, the flight momentarily encountered "large bumps" and two FAs were thrown to the floor after having just gotten out of their jump seats to finish cleaning up the aft galley. As a result, one FA experienced severe pain in her leg and was unable to complete her duties for the remainder of the flight. The captain was immediately informed of the injured FAs condition and medical assistance was requested to meet the airplane at the gate. After an uneventful landing, the FA was transported to the hospital and diagnosed with a broken leg. ## Aircraft - Registration: [N936WN](https://openairdocs.org/aircraft/N936WN), registered now, S/N 36643, built 2009 (OpenAirDocs) - Reported make and model: BOEING 737 7H4 (7H4) - Registry model: [Boeing 737-7H4](https://openairdocs.org/model/boeing-737-7h4) (registry code 1384404) (OpenAirDocs) - Registry engine: [CFM International CFM56-7B24/3 series](https://openairdocs.org/engine/cfm-international-cfm56-7b24-3-series) (registry code 13074, turbo-fan) (OpenAirDocs) - Category: Airplane - Serial number: 36643 - Year built: 2009 - Airframe hours: 8317 - Engines: CFM INTL CFM56-7B24/3 24000 lbs thrust turbo fan; CFM INTL CFM56-7B24/3 24000 lbs thrust turbo fan - Damage: No damage - Flight: Part 121 - Operator: Southwest Airlines - Registered owner: Southwest Airlines Co - Airworthiness certificate: Standard, Transport - Last inspection: Continuous airworthiness, April 25, 2011 - Departed: KMDW, Chicago, IL - Destination: KFLL, Fort Lauderdale, FL - Flight plan: IFR - Equipment: Stall warning system, Data recorder, Auto-pilot ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 58; injuries: none; airline transport, flight instructor; airplane ratings: single-engine land, multi-engine land, single-engine sea; instrument ratings: airplane; medical: class 1, without waivers/limitations; seat: left; restraint: 5-point; flight hours: 18,500 total, 12,500 in this make and model, 13,500 as pilot in command, 245 in the last 90 days, 87 in the last 30 days, 7 in the last 24 hours - Co-pilot; age 38; injuries: none; airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review November 7, 2010; seat: right; restraint: 5-point; flight hours: 12,852 total, 3,382 in this make and model, 7,506 as pilot in command, 164 in the last 90 days, 46 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 230° at 4 knots - Lowest ceiling: 5,000 ft broken - Temperature: 81 °F, dew point 72 °F - Altimeter: 29.89 inHg - Turbulence: Moderate - Observed at: KRSW, 27 nm away ## Docket (1 files) The files NTSB released with the investigation on February 23, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=82964. 498 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 498 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40449542&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF 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.