National Transportation Safety Board
Aviation Accident Final Report

 

 

Location:

Atlanta, GA

Accident Number:

DCA13CA128

Date & Time:

07/12/2013, 0538 EDT

Registration:

N863DA

Aircraft:

BOEING 777-232

Aircraft Damage:

None

Defining Event:

Turbulence encounter

Injuries:

1 Serious, 278 None

Flight Conducted Under:

Part 121: Air Carrier - Scheduled

Analysis

According to the flight and cabin crew statements, Atlanta Approach Control advised the crew that radar was showing an area of rain on the arrival route although the flight crew did not see any areas of precipitation on the airborne weather radar. During the descent to 11,000 feet the seatbelt sign was illuminated and the captain, who was the pilot monitoring, cycled the seatbelt sign and called the flight attendant (FA) at the 1L door via the interphone to notify the cabin crew to be seated.   Before the 1L flight attendant was able to relay the message to all of the FAs to be seated, as they were all preparing the cabin for arrival, the airplane encountered several distinct jolts of turbulence. According to the flight data recorder data, as the airplane was descending through about 13,200 feet, the vertical acceleration fluctuated between +1.56 g's and +0.024 g's over a period of about 10 seconds.

During the turbulence the 4Rc FA who was in the aisle near the 3R door was lifted into the air and fell back down to the floor on her feet and knees.  The FA was assisted to the 3R jumpseat, the flight crew was notified of the injury, and they requested paramedics meet the airplane upon arrival 

The 4Rc FA was transported to the hospital where she was diagnosed with two broken ankles.

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
Unexpected encounter with convective turbulence while the flight attendants were preparing the cabin for arrival.

Findings

Environmental issues

Convective turbulence - Effect on personnel (Cause)

Factual Information

According to the flight and cabin crew statements, Atlanta Approach Control advised the crew that radar was showing an area of rain on the arrival route although the flight crew did not see any areas of precipitation on the airborne weather radar. During the descent to 11,000 feet the seatbelt sign was illuminated and the captain, who was the pilot monitoring, cycled the seatbelt sign and called the flight attendant (FA) at the 1L door via the interphone to notify the cabin crew to be seated.   Before the 1L flight attendant was able to relay the message to all of the FAs to be seated, as they were all preparing the cabin for arrival, the airplane encountered several distinct jolts of turbulence. According to the flight data recorder data, as the airplane was descending through about 13,200 feet, the vertical acceleration fluctuated between +1.56 g's and +0.024 g's over a period of about 10 seconds.

During the turbulence the 4Rc FA who was in the aisle near the 3R door was lifted into the air and fell back down to the floor on her feet and knees.  The FA was assisted to the 3R jumpseat, the flight crew was notified of the injury, and they requested paramedics meet the airplane upon arrival 

The 4Rc FA was transported to the hospital where she was diagnosed with two broken ankles.

 

History of Flight

Enroute-descent

Turbulence encounter (Defining event)

 

 

Pilot Information

Certificate:

Airline Transport

Age:

56

Airplane Rating(s):

Multi-engine Land; Single-engine Land

Seat Occupied:

Left

Other Aircraft Rating(s):

Glider

Restraint Used:

Seatbelt, Shoulder harness

Instrument Rating(s):

Airplane

Second Pilot Present:

Yes

Instructor Rating(s):

None

Toxicology Performed:

No

Medical Certification:

Class 1 Unknown

Last FAA Medical Exam:

06/26/2013

Occupational Pilot:

Yes

Last Flight Review or Equivalent:

05/05/2013

Flight Time:

13394 hours (Total, all aircraft), 1136 hours (Total, this make and model), 5757 hours (Pilot In Command, all aircraft), 87 hours (Last 90 days, all aircraft), 1 hours (Last 24 hours, all aircraft)

 

 

Co-Pilot Information

Certificate:

Airline Transport

Age:

52

Airplane Rating(s):

Multi-engine Land; Single-engine Land

Seat Occupied:

Right

Other Aircraft Rating(s):

None

Restraint Used:

Seatbelt, Shoulder harness

Instrument Rating(s):

Airplane

Second Pilot Present:

Yes

Instructor Rating(s):

None

Toxicology Performed:

No

Medical Certification:

Class 1 Unknown

Last FAA Medical Exam:

02/20/2013

Occupational Pilot:

Yes

Last Flight Review or Equivalent:

01/15/2013

Flight Time:

9499 hours (Total, all aircraft), 616 hours (Total, this make and model), 517 hours (Pilot In Command, all aircraft), 94 hours (Last 90 days, all aircraft), 1 hours (Last 24 hours, all aircraft)

 

 

Aircraft and Owner/Operator Information

Aircraft Make:

BOEING

Registration:

N863DA

Model/Series:

777-232

Aircraft Category:

Airplane

Year of Manufacture:

 

Amateur Built:

No

Airworthiness Certificate:

Transport

Serial Number:

29735

Landing Gear Type:

Retractable - Tricycle

Seats:

400

Date/Type of Last Inspection:

 

Certified Max Gross Wt.:

 

Time Since Last Inspection:

 

Engines:

2 Turbo Jet

Airframe Total Time:

 

Engine Manufacturer:

ROLLS-ROYC

ELT:

 

Engine Model/Series:

RB.211 SERIES

Registered Owner:

DELTA AIR LINES INC

Rated Power:

22000 lbs

Operator:

DELTA AIR LINES INC

Operating Certificate(s) Held:

Flag carrier (121)

Operator Does Business As:

 

Operator Designator Code:

DALA

 

Meteorological Information and Flight Plan

Conditions at Accident Site:

Visual Conditions

Condition of Light:

Night/Dark

Observation Facility, Elevation:

KATL

Distance from Accident Site:

29 Nautical Miles

Observation Time:

0452 EDT

Direction from Accident Site:

227°

Lowest Cloud Condition:

Scattered / 3200 ft agl

Visibility

7 Miles

Lowest Ceiling:

Broken / 4800 ft agl

Visibility (RVR):

 

Wind Speed/Gusts:

Calm /

Turbulence Type Forecast/Actual:

/

Wind Direction:

 

Turbulence Severity Forecast/Actual:

/

Altimeter Setting:

29.91 inches Hg

Temperature/Dew Point:

23°C / 22°C

Precipitation and Obscuration:

 

Departure Point:

Dubai, FN (OMDB)

Type of Flight Plan Filed:

IFR

Destination:

Atlanta, GA (KATL)

Type of Clearance:

IFR

Departure Time:

1138 UTC

Type of Airspace:

 

 

 

Wreckage and Impact Information

Crew Injuries:

1 Serious, 14 None

Aircraft Damage:

None

Passenger Injuries:

264 None

Aircraft Fire:

None

Ground Injuries:

N/A

Aircraft Explosion:

None

Total Injuries:

1 Serious, 278 None

Latitude, Longitude:

33.910000, -84.083056 (est)

 


 


Administrative Information

Investigator In Charge (IIC):

David Helson

Report Date:

09/01/2015

Additional Participating Persons:

 

Publish Date:

09/01/2015

Note:

This accident report documents the factual circumstances of this accident as described to the NTSB.

Investigation Docket:

http://dms.ntsb.gov/pubdms/search/dockList.cfm?mKey=87472