# NTSB DCA19CA091: Boeing 737, N3730B, Franklin, TN, February 18, 2019 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Class 4 · Data collection · Final report - Date: February 17, 2019, 18:04 local (Feb 18, 2019, 00:04 UTC) - Place: Franklin, TN - Coordinates: 35.90139, -86.957221 - Nearby events: https://openairdocs.org/map.md?lat=35.9014&lon=-86.9572&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, 1 minor, 143 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Major Investigations Division - NTSB case key (mKey): 99058 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DCA19CA091 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/99058/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=99058 - Page: https://openairdocs.org/ntsb/DCA19CA091 ## Probable cause an encounter with convective turbulence during 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 737-832, 1 case](https://openairdocs.org/ntsb-findings/03032020/cases.md?model=13844CF), [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 737-832, 2 cases](https://openairdocs.org/ntsb-events/360/sequence.md?model=13844CF), [All aircraft, 423 cases](https://openairdocs.org/ntsb-events/360/sequence.md) ## Analysis On February 17, 2019, about 1804 central standard time, Delta Air Lines flight 957, a Boeing 737-800, N3730B, encountered turbulence during descent into Atlanta Hartsfield-Jackson International Airport (KATL), Atlanta, Georgia. Of the 145 passengers and crew onboard, one flight attendant sustained serious injuries and one received minor injuries. The airplane was not damaged. The flight was operating under 14 Code of Federal Regulations Part 121 as a regularly scheduled passenger flight from Bozeman Yellowstone International Airport (KBZN), Bozeman, Montana, to KATL. According to the flight crew, air traffic control informed them to expect light and occasional moderate turbulence during the descent. About 10 minutes before beginning their descent, the flight crew illuminated the seat belt sign and instructed the flight attendants (FA) to stow the carts and take their seats. Shortly after departing FL350 for FL250, and the airplane encountered two “rapid-bumps of light-moderate turbulence” at approximately FL345. The flight crew slowed the airplane and contacted the FAs and was informed that the aft FA was injured. According to the flight attendants, the flight had been routine, having experienced only occasional light turbulence. The two aft FAs had finished their meal service and secured the galley. The two FAs were making their final walkthrough of the cabin when the captain made the public address announcement to discontinue cabin service, when the turbulence was encountered. The two aft FAs reported they were thrown up to the ceiling and then came “crashing back down” onto the galley floor. One of the FAs was in intense pain after striking the floor hard and was attended to by two medically qualified passengers. The FA was moved to an empty passenger row for landing and was provided oxygen and pain medication. The flight crew declared an emergency and requested paramedics meet the flight at the gate. The FA was transported to the hospital where she was diagnosed with a fractured vertebra. Post accident examination of the weather data determined that the accident flight was in instrument meteorological conditions (IMC) in an area of convectively induced turbulence due to embedded rain shower activity when the turbulence was encountered. While there was no lightning activity around the accident site at the accident time, there were pockets of strong rain shower cells within the complex of precipitation as a whole. The area where the accident occurred was covered by AIRMET Tango that warned of moderate turbulence conditions. ## Aircraft - Registration: [N3730B](https://openairdocs.org/aircraft/N3730B), registered now, S/N 30538, built 2000 (OpenAirDocs) - Reported make and model: Boeing 737 (832) - Registry model: [Boeing 737-832](https://openairdocs.org/model/boeing-737-832) (registry code 13844CF) (OpenAirDocs) - Registry engine: [CFM International CFM56 series](https://openairdocs.org/engine/cfm-international-cfm56-series) (registry code 13802, turbo-fan) (OpenAirDocs) - Category: Airplane - Serial number: 30538 - Year built: 2000 - Airframe hours: 54653 - Engines: CFM CFM56-7B26 26300 lbs thrust turbo fan; CFM CFM56-7B26 26300 lbs thrust turbo fan - Damage: No damage - Flight: Part 121 - Operator: Delta Air Lines Inc - Registered owner: Delta Air Lines Inc - Airworthiness certificate: Standard, Transport - Last inspection: Continuous airworthiness, February 16, 2019 - Departed: KBZN, Bozeman, MT - Destination: KATL, Atlanta, GA - Flight plan: IFR - Equipment: Stall warning system, Onboard weather, Heads up display, ADS-B, Electronic primary flight display, Electronic multifunction display, Electronic flight bag or handheld device, Data recorder, Auto-pilot, Angle of attack indicator ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 63; injuries: none; airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review September 15, 2018; seat: left; flight hours: 16,098 total, 6,637 in this make and model, 4,161 as pilot in command, 186 in the last 90 days, 5 in the last 24 hours - Co-pilot; age 38; injuries: none; airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review January 7, 2019; seat: right; flight hours: 1,308 total, 83 in this make and model, 97 in the last 90 days, 2 in the last 24 hours - Cabin crew; injuries: none; medical: unknown; seat: none; restraint: none; flight hours: 0 total, 0 in this make and model - Cabin crew; injuries: none; medical: unknown; seat: none; restraint: none; flight hours: 0 total, 0 in this make and model - Cabin crew; injuries: minor; medical: unknown; seat: none; restraint: none; flight hours: 0 total, 0 in this make and model - Cabin crew; injuries: serious; medical: unknown; seat: none; restraint: none; flight hours: 0 total, 0 in this make and model ## Weather - Conditions: Instrument (IMC), Night - Wind: 100° at 6 knots - Visibility: 0.25 statute miles - Temperature: 48 °F, dew point 48 °F - Altimeter: 29.86 inHg - Icing: Unknown - Observed at: KATL, 184 nm away ## Other investigations on N3730B (1) 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. - [NTSB DCA10CA075](https://openairdocs.org/ntsb/DCA10CA075), Jun 19, 2010: Boeing 737 (N3730B), New York, NY, substantial damage. Probable cause: a baggage cart impacting the airplane and causing substantial damage as a result of the jet blast from a passing airplane. ## Docket (19 files) The files NTSB released with the investigation on July 13, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=99058. 330 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 487 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9659455&FileExtension=pdf&FileName=6120%20Form-Rel.pdf - Weather study report (item 2, PDF, 30 pages, 2.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8524466&FileExtension=pdf&FileName=DCA19CA091_weatherstudySuffernfinal-Rel.pdf - Weather attachment 1 (item 3, GIF, 3.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8524973&FileExtension=gif&FileName=attachment1_IRsatanimation2330to0030utc-Rel.gif - Weather attachment 2 (item 4, GIF, 12.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8524475&FileExtension=gif&FileName=attachment2_animationwxreflectivity2327to0027utc_0_5degree-Rel.gif - Weather attachment 3 (item 5, GIF, 9.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8524484&FileExtension=gif&FileName=attachment3_animationwxreflectivity2327to0027utc_10degree-Rel.gif - Weather attachment 4 (item 6, PDF, 5 pages, 2.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8523987&FileExtension=pdf&FileName=attachment4_GFAimagedata-Rel.pdf - Weather attachment 5 (item 7, PDF, 15 pages, 506 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8524982&FileExtension=pdf&FileName=attachment5_DL957%2017Feb2019%20BZN-ATL-Rel.pdf - Weather attachment 6 (item 8, ZIP, 294 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8524991&FileExtension=zip&FileName=attachment6_20190217-20190717T162349Z-001-Rel.zip - Operational factors specialists report (item 9, PDF, 41 pages, 1.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8894573&FileExtension=pdf&FileName=DCA19CA091%20-%20Specialist%20Report%20%20-%20Final-Rel.pdf - Operational factors - attachment 1 - crew statements (item 10, PDF, 8 pages, 342 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8884806&FileExtension=pdf&FileName=Attachment%201%20-%20Crew%20Statements_Redacted-Rel.pdf - Operational factors - attachment 2 - flight crew training records [excerpts] (item 11, PDF, 4 pages, 124 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8883721&FileExtension=pdf&FileName=Attachment%202%20-%20Flight%20Crew%20Training%20Records_Redacted-Rel.pdf - Operational factors - attachment 3 - accident flight weight data records (item 12, PDF, 7 pages, 66 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8884499&FileExtension=pdf&FileName=Attachment%203%20-%20Accident%20Flight%20Weight%20Data%20Record_Redacted-Rel.pdf - Operational factors - attachment 4 - accident flight release (item 13, PDF, 30 pages, 113 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8884200&FileExtension=pdf&FileName=Attachment%204%20-%20Accident%20Flight%20Release_Redacted-Rel.pdf - Operational factors - attachment 5 - acars message [excerpts] (item 14, PDF, 3 pages, 63 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8883898&FileExtension=pdf&FileName=Attachment%205%20-%20Turbulence%20ACARS%20Message_Redacted-Rel.pdf - Operational factors - attachment 6 - archived pireps (item 15, CSV, 55 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8883730&FileExtension=csv&FileName=Archieved%20PIREPs-Rel.csv - Operational factors - attachment 7 - delta air lines airway manual [excerpts] (item 16, PDF, 7 pages, 174 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8884316&FileExtension=pdf&FileName=Attachment%207%20-%20Delta%20Air%20Lines%20Airway%20Manual%20%5BExcerpts%5D-Rel.pdf - Operational factors - attachment 8 - delta air lines flight operations manual [excerpts] (item 17, PDF, 10 pages, 315 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8882816&FileExtension=pdf&FileName=Attachment%208%20-%20Delta%20Air%20Lines%20Flight%20Operations%20Manual-Rel.pdf - Operational factors - attachment 9 - delta air lines operations manual [excerpts] (item 18, PDF, 10 pages, 280 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8884701&FileExtension=pdf&FileName=Attachment%209%20-%20Delta%20Air%20Lines%20Operations%20Manuals-Rel.pdf - Operational factors - attachment 10 - delta air lines on-board manual [excerpts] (item 19, PDF, 7 pages, 1.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8884634&FileExtension=pdf&FileName=Attachment%2010%20-%20Delta%20Air%20Lines%20On-Board%20Manual-Rel.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.