# NTSB ERA09LA418: Boeing 757, N657DL, Cuba, Cuba, May 16, 2009 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: May 16, 2009, 11:45 local (15:45 UTC) - Place: Cuba, Cuba - Coordinates: 23.116666, -81.233329 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=23.1167&lon=-81.2333&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Turbulence encounter](https://openairdocs.org/ntsb-events/360) - Highest injury: Serious injuries - Injuries: 1 serious, 4 minor, 184 uninjured - Status: Completed, report August 12, 2010 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: Delta Airlines - NTSB case key (mKey): 74357 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA09LA418 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/74357/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=74357 - Page: https://openairdocs.org/ntsb/ERA09LA418 ## Probable cause An unanticipated inflight encounter with turbulence. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Turbulence](https://openairdocs.org/ntsb-findings/03032000): Environmental issues › Conditions/weather/phenomena · Effect on personnel (probable cause); cases with it: [Boeing 757-232, 1 case](https://openairdocs.org/ntsb-findings/03032000/cases.md?model=1384965), [All aircraft, 92 cases](https://openairdocs.org/ntsb-findings/03032000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Turbulence encounter](https://openairdocs.org/ntsb-events/360) (defining event); cases with it: [Boeing 757-232, 6 cases](https://openairdocs.org/ntsb-events/360/sequence.md?model=1384965), [All aircraft, 423 cases](https://openairdocs.org/ntsb-events/360/sequence.md) ## Analysis The airplane was at flight level 350 with the autopilot engaged, and about 35 to 40 minutes from its destination, when it encountered severe turbulence. The captain had turned the seat belt light on 5 to 10 minutes before the turbulence, and the first officer had made the public address announcing that everyone needed to remain seated with their seatbelts fastened. Suddenly, the airplane encountered severe turbulence and climbed rapidly to about 500 feet above the assigned altitude; the autopilot then disengaged. The captain took control of the airplane and slowly lowered the nose. As the captain leveled the airplane, the nose pitched down and the airplane descended about 500 feet below the assigned altitude before leveling and departing the area of turbulence. At the time of the encounter, the airplane was in a layer of haze. There was no heavy precipitation noted on the radar, and no build-ups visible to the flight crew. One passenger was seriously injured, and two passengers and two flight attendants sustained minor injuries. ## Factual narrative On May 16, 2009, at 1145 eastern daylight time, a Boeing 757-232, N657DL, operating as Delta Airlines flight 687, encountered turbulence while in cruise flight over Cuba. One passenger was seriously injured, and two passengers and two flight attendants sustained minor injuries. The captain, first officer, 2 flight attendants, and 180 passengers were not injured, and the airplane was not damaged. The flight was operating on an instrument flight rules flight plan under the provisions of Title 14, Code of Federal Regulations (CFR) Part 121. Instrument meteorological conditions prevailed in the vicinity of the turbulence. The flight departed from Hartsville Jackson International Airport (KATL), Atlanta, Georgia, at 1052, and was en route to Owen Roberts International Airport (MWCR), George Town, Cayman Islands. According to the captain, the airplane was at flight level 350, with the autopilot engaged, about 35 to 40 minutes from MWCR in Cuban airspace. He had turned the seat belt light on 5 to 10 minutes earlier, and the first officer had made the public address announcement that everyone needed to remain seated with their seatbelts fastened. The airplane was in a haze layer, the radar was on and painted only small patches of green, no yellow or red was showing, and there were no buildups up ahead. All of a sudden, the “ride” became severe, as the airplane climbed rapidly, to approximately 500 feet above the assigned altitude, and the autopilot disengaged. The captain took control of the yoke to stop the climb and slowly lowered the nose. As he was trying to level the airplane, it then pitched down, and was recovered about 500 feet below cruise altitude. The first officer attempted to communicate the event to the Cuban controller but language difficulties intervened. The captain stated that the event probably lasted about a minute, or slightly longer. The first officer called the cabin to assess any injuries; he was informed by a flight attendant that at least two, and perhaps three passengers appeared to be injured, as well as a flight attendant who had hurt her wrist and shoulder. The captain contacted the destination controller and requested that medical personnel meet the flight. Three passengers were transported to the local hospital for assessment. The flight attendant declined further treatment until returning to Atlanta. The lead flight attendant confirmed that the seat belt light had been on when the turbulence occurred. ## Aircraft - Registration: [N657DL](https://openairdocs.org/deregistered/N657DL-2019-02-12), registration cancelled 2019-02-12, S/N 24419, built 1990 (OpenAirDocs) - Reported make and model: BOEING 757 (232) - Registry model: [Boeing 757-232](https://openairdocs.org/model/boeing-757-232) (registry code 1384965) (OpenAirDocs) - Registry engine: [Pratt & Whitney PW2037](https://openairdocs.org/engine/pratt-whitney-pw2037) (registry code 52117, turbo-fan) (OpenAirDocs) - Category: Airplane - Serial number: 24419 - Airframe hours: 63598 - Engines: Pratt & Whitney PW2037 37000 lbs thrust turbo fan; Pratt & Whitney PW2037 37000 lbs thrust turbo fan - Damage: No damage - Flight: Part 121 - Operator: Delta Air Lines, Inc. - Registered owner: Wilmington Trust Co Trustee - Airworthiness certificate: Standard, Transport - Last inspection: Continuous airworthiness, May 9, 2009 - Departed: ATL, Atlanta, GA - Destination: MWCR, George Town - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; injuries: none; airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: helicopter, airplane; medical: class 1, without waivers/limitations; last flight review August 29, 2008; seat: left; flight hours: 8,830 total, 4,328 in this make and model - Co-pilot; age 44; injuries: none; airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane, helicopter; medical: class 1, without waivers/limitations; last flight review October 8, 2008; seat: right; flight hours: 4,152 total, 697 in this make and model ## Weather - Conditions: Instrument (IMC), Day - Wind: 360° at 13 knots, gusting 19 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 63 °F, dew point 52 °F - Altimeter: 30.28 inHg - Observed at: MWCR ## Docket (3 files) The files NTSB released with the investigation on June 28, 2010, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=74357. 786 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 565 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40329315&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Flight Crew Statements (item 2, .PDF, 130 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40329316&FileExtension=.PDF&FileName=Flight%20Crew%20Statements-Redacted.PDF - Cabin Crew Statements (item 3, .PDF, 90 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40329317&FileExtension=.PDF&FileName=Cabin%20Crew%20Statements-Redacted.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.