Cases › DCA18MA142 › The analyst
BOEING 737 7H4SOUTHWEST AIRLINES CO
What the docket says, assembled. No language model is involved, so nothing on this page can be invented — every line traces to a recorder, a report page or the Board's own record.
53
timed facts
8
precedents
108
passages to ask
Ask the docket
passages, not paraphrasesTry
Every answer is a passage of the docket with the page it came from, or the words “not in the docket”. Nothing is summarised or reasoned for you — read the source.
One timeline
53 timed factsthe recorder events from the FDR report, with the transcript's warnings, callouts, the words nearest each event and the final seconds — on one clock, as printed in each report- 10:31 (approx)FDRPre-taxip.4Engines started, number two (right) engine first and number one (left) engine secondsee the traces at this moment ↗
- 10:42:34FDRTakeoffp.4Engines began accelerating to takeoff powersee the traces at this moment ↗
- 10:43:11FDRTakeoff rollp.4Pitch began to increase at computed airspeed of 123 ktssee the traces at this moment ↗
- 10:43:20FDRTakeoff/liftoffp.4Gear weight on wheels signal transitioned from ground to air at computed airspeed of 157 ktssee the traces at this moment ↗
- ~10:50FDRClimbp.5Aircraft climbed steadily for about seven minutes to a pressure altitude of about 17,250 ftsee the traces at this moment ↗
- 10:52:58CVR HOTp.7“[sound of flight attendant call chime].”read in context ↗
- 10:56:58CVR RDO-1p.9“Southwest thirteen eighty up to flight level two eight zero.”read in context ↗
- ~10:57FDRClimbp.5After three minutes at 22,000 ft, aircraft began to climb againsee the traces at this moment ↗
- 10:57:02CVR HOT-2p.9“twenty eight.”read in context ↗
- 11:03:33.2FDRCruise/climbp.5Approximate time of fan blade off event; pressure altitude about 32,648 ft; engine 1 fan and core speeds decreased immediately and engine 1 vibration levels were elevatedsee the traces at this moment ↗
- 11:03:33.3FDRPost fan blade offp.5Discontinuity occurred in the data with missing data of at least 0.09 seconds, likely due to a momentary power interruption to the recording systemsee the traces at this moment ↗
- 11:03:35FDRPost fan blade offp.5Engine 1 control recorded a flameout protection recovery mode activesee the traces at this moment ↗
- 11:03:39FDRDepressurizationp.5Cabin Altitude Warning recorded, signifying cabin altitude exceeded 10,000 ftsee the traces at this moment ↗
- 11:03:39CVR CAMwarningp.10“[sound of cabin altitude warning horn].”read in context ↗
- 11:03:42CVR HOT-1p.11“*.”read in context ↗
- 11:03:43FDREmergency descentp.5Aircraft began a rapid descent with descent rates in excess of 5,000 feet per minutesee the traces at this moment ↗
- 11 seconds after discontinuity (~11:03:44.3)FDRUpsetp.5Aircraft reached peak recorded value of 41.3 degrees left roll before coming back to level attitude; roll was uncommanded, pilot inputs and force to the rightsee the traces at this moment ↗
- 11:03:46CVR HOT-1p.11“* * *.”read in context ↗
- 11:03:48FDRPost fan blade offp.5Engine 1 Fault Dispatch Level A fault was recorded, correlated to a T12 (fan bypass duct temperature) faultsee the traces at this moment ↗
- 11:04:08CVR HOT-1p.11“* * *.”read in context ↗
- 11:04:09FDRPost fan blade offp.4Engine 1 fuel switch position transitioned from Run to Cutoff, ending flameout protection recovery modesee the traces at this moment ↗
- 11:04:21CVR CTRp.11“Southwest thirteen eighty cleared direct VINSE V-I-N- S-E.”read in context ↗
- 11:04:54CVR RDO-1warningp.12“Southwest thirteen eighty has an engine fire descending.”read in context ↗
- 11:06:02CVR CAMwarningp.14“bank angle [electronic voice].”read in context ↗
- 11:06:33CVR CAMwarningp.14“bank angle, bank angle [electronic voice].”read in context ↗
- 11:08:12CVR RDO-1warningp.17“center Southwest thirteen eighty declaring an emergency going through seventeen thousand need your local altimeter.”read in context ↗
- 11:10:33CVR HOT-2warningp.21“engine fire switch confirm pull?”read in context ↗
- 11:10:45CVR HOT-2warningp.22“engine fire switch on or overheat light illuminated rotate if not illuminated.”read in context ↗
- 11:10:53CVR HOT-1calloutp.22“alright then don't rotate it.”read in context ↗
- 11:10:56CVR CAMwarningp.22“[sound of fire bell].”read in context ↗
- 11:11:59CVR RDO-1warningp.24“engine ah engine severe damage. engine failure. and exact pounds of fuel * fifteen seventeen twenty one * thousand.”read in context ↗
- 11:12:23CVR HOT-1p.25“think we had a rapid D as well.”read in context ↗
- 11:12:24FDRDescentp.5Cabin Altitude Warning ceased when aircraft pressure altitude was about 9,150 ftsee the traces at this moment ↗
- 11:12:25CVR CAM-2p.25“I know.”read in context ↗
- 11:16:56CVR CAMwarningp.35“[sound of altitude alert tone].”read in context ↗
- 11:17:35CVR CAMwarningp.36“[sound of altitude alert tone].”read in context ↗
- 11:18:59CVR TWRcalloutp.39“Southwest thirteen eighty runway two seven left cleared to land wind two eight zero at one nine gust two five.”read in context ↗
- 11:19:06CVR RDO-2calloutp.39“two seven left cleared to land ah Southwest thirteen eighty.”read in context ↗
- 11:19:49CVR HOT-2calloutp.40“okay five hundred feet. landing gear down. flaps five. speed brakes * armed.”read in context ↗
- 11:20:02CVR CAMwarningp.41“glide slope, glide slope, glide slope, glide slop, glide slope [electronic voice]. too low terrain [electronic voice].”read in context ↗
- 11:20:10CVR CAMwarningp.42“glide slope, glide slope, glide slope, glide slop, glide slope [electronic voice]. too low terrain, too low terrain [electronic voice].”read in context ↗
- 11:20:20CVR CAMwarningp.42“glide slope [electronic voice]. too low terrain, too low terrain [electronic voice].”read in context ↗
- 11:20:27CVR CAMp.43“ten [electronic voice].”read in context ↗
- 11:20:30FDRLandingp.5Aircraft touched down with flaps set at 5 degrees at approximately 171 kts; reverse thrust used on right enginesee the traces at this moment ↗
- 11:20:31CVR HOT-2p.43“'kay, extended.”read in context ↗
- 12:30:25CVR CAMfinal secondsp.87“[sounds consistent with deplaning activities and crew conversations with ground-based personnel].”read in context ↗
- 12:35:37CVR CAM-2final secondsp.87“@ @.”read in context ↗
- 12:35:38CVR CAM-1final secondsp.87“yeah?”read in context ↗
- 12:35:38CVR CAM-2final secondsp.87“DOM is going to take it just leave it * leave * the APU goin'.”read in context ↗
- 12:35:42CVR CAM-1final secondsp.87“okay.”read in context ↗
- 12:35:56CVR CAMfinal secondsp.87“[unintelligible background conversations].”read in context ↗
- 12:38:56CVR CAMfinal secondsp.87“[sound similar to fire siren].”read in context ↗
- 12:39:03CVR CAMfinal secondsp.87“[sounds consistent with ground personnel entering the plane for movement off the field].”read in context ↗
10 - Flight Data Recorder - Factual · 16 events extracted by claude-sonnet-512 - Cockpit Voice Recorder Factual · 37 of 672 lines shown
How the Board coded the sequence
- Enroute-climb to cruise: Powerplant sys/comp malf/fail
Precedents
8 closest casesranked by what happened, in the Board's words, and by the findings and occurrences it coded- BOEING 737-700 · Southwest AirlinesPensacola, FL
- ●Aircraft › Aircraft power plant › Engine (turbine/turboprop)
- ●Aircraft › Aircraft structures › Nacelles/pylons structure
Powerplant sys/comp malf/fail - BOEING 777-222 · United AirlinesBroomfield, CO
- ●Aircraft › Aircraft power plant › Engine (turbine/turboprop)
Powerplant sys/comp malf/fail - BOEING 757 · DELTA AIR LINES INCLas Vegas, NV
- ●Aircraft › Aircraft power plant › Engine (turbine/turboprop)
Powerplant sys/comp malf/fail - BOEING 777 · Delta Air LinesAtlanta, GA
- ●Aircraft › Aircraft power plant › Engine (turbine/turboprop)
Powerplant sys/comp malf/fail - BOMBARDIER INC CL 600 2B19 · Endeavor AirBaltimore, MD
- ●Aircraft › Aircraft power plant › Engine (turbine/turboprop)
Powerplant sys/comp malf/fail - AIRBUS A319 132 · Spirit AirlinesGreenville, TX
- ●Aircraft › Aircraft power plant › Engine (turbine/turboprop)
Powerplant sys/comp malf/fail - BOEING 777 222 · UNITED AIRLINES INCHonolulu, HIPowerplant sys/comp malf/fail
- BOEING 757-232 · DELTA AIR LINES INCAtlanta, GA
- ●Aircraft › Aircraft power plant › Engine (turbine/turboprop)
Powerplant sys/comp malf/fail
What the record says
a pattern, not a findingacross the 8 closest cases · 8 carry coded findings · 8 have a probable causeFindings the Board cited in those cases
- 7 of 8Aircraft › Aircraft power plant › Engine (turbine/turboprop)cited here too
- 3 of 8Organizational issues › Development › Design
- 2 of 8Organizational issues › Support/oversight/monitoring › Oversight
Occurrences it coded
- 8 of 8Powerplant sys/comp malf/fail
Set against the Board’s own findings for this case
Cited here, and common in the precedents
- Aircraft power plant › Engine (turbine/turboprop)
Cited here, not seen in the precedents
- Aircraft structures › Windows-windshield system
Common in the precedents, not cited here
- Development › Design
- Support/oversight/monitoring › Oversight
A teaching device, not a verdict: what the record would have looked at, next to what the Board found.
In the Board’s words — the closest cases
- DCA16FA2172016-08-27 · BOEING 737-700 · Southwest Airlines
A low-cycle fatigue crack in the dovetail of fan blade No. 23, which resulted in the fan blade separating in flight and impacting the fan case. This impact caused the fan blade to fracture into fragments that traveled farther than expected into the inlet, which compromised the structural integrity of the inlet and led to the in-flight separation of inlet components. A portion of the inlet struck the fuselage and created a hole, causing the cabin to depressurize.
- DCA21FA0852021-02-20 · BOEING 777-222 · United Airlines
The fatigue failure of the right engine fan blade. Contributing to the fan blade failure was the inadequate inspection of the blades, which failed to identify low-level indications of cracking, and the insufficient frequency of the manufacturer’s inspection intervals, which permitted the low-level crack indications to propagate undetected and ultimately resulted in the fatigue failure. Contributing to the severity of the engine damage following the fan blade failure was the design and testing of the engine inlet, w…
- ENG08IA0382008-08-06 · BOEING 757 · DELTA AIR LINES INC
The engine experienced an uncontained release of high pressure turbine material due to fatigue cracks that occurred on four consecutive blade retainig lugs on the 2nd stage turbine hub. The cracked lugs resulted in the release of four 2nd stage turbine blades that penetrated the engine's cases and nacelle. The lugs cracked due to loss of material and resultant increase in stress load on the blade slot serrations due to excessve grit blasting when the hub was being overhauled by Delta Air Lines. Contributing to the…
- ENG09IA0022009-01-02 · BOEING 777 · Delta Air Lines
The fan blade fractured due to a fatigue crack that was the result of the combination of the breakdown of the fan blade lubrication system and residual fatigue life usage following the last overhaul of the fan blade. Contributing to the fracture was the inadequate lubrication schedule established by the engine manufacturer that was not reflective of the operator’s use of the engine.
- ENG17IA0082017-01-23 · BOMBARDIER INC CL 600 2B19 · Endeavor Air
A Bombardier CRJ200 No. 2 engine failure due to the separation of a fan blade airfoil at a low cycle fatigue crack that originated at the forward fan blade pin hole attachment. The separated fan blade had previously undergone a hot form repair and both metallurgical analysis and repair records indicated that the lance/shot peen step required to restore sufficient residual stress levels to the blade material was not completed.
What it recommended after them
- A-08-085TO THE FEDERAL AVIATION ADMINISTRATION: Require that Pratt & Whitney PW2037 engines be removed from service for inspection of the 2nd stage turbine hubs when they have accumulated significantly fewer hours and/or cycles than the incident en… · ENG08IA038Closed - Unacceptable Action
- A-08-086TO THE FEDERAL AVIATION ADMINISTRATION: Require that Pratt & Whitney PW2037 2nd stage turbine hubs undergo recurring inspections when they have accumulated significantly fewer hours and/or cycles than the incident engine (10,880 hours and/o… · ENG08IA038Closed - Acceptable Action
This is the pattern in the NTSB’s own record across similar accidents — which findings it cited, what it coded, what it recommended. It is drawn from the record, not written about this case, and it never assigns blame: investigations exist to prevent the next accident (ICAO Annex 13).