Cases › DCA18IA092 › The analyst
BOEING 777 222UNITED AIRLINES INC
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.
1
timed facts
8
precedents
49
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
1 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- 11:58:27 HSTFDRCruise (Level flight at FL360)p.5The event occurred (in-flight separation of a fan blade as well as the inlet duct and fan cowls of the Number 2 (right) engine)
Recorder events without a clock time
- 1200 HST (approximate)Flight crew heard a loud bang followed by violent shaking of the airplane followed by warnings of a compressor stall
- 1200 HST (approximate, after event)Flight crew shut down the engine and declared an emergency
- 1237 HSTAirplane landed at HNL for a single-engine landing without further incident
Flight Data Recorder - Specialist's Factual Report · 4 events extracted by claude-sonnet-5
How the Board coded the sequence
- Enroute-descent: 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 777 · Delta Air LinesAtlanta, GA
- ●Organizational issues › Support/oversight/monitoring › Oversight
Powerplant sys/comp malf/fail - BOEING 777-222 · United AirlinesBroomfield, COPowerplant sys/comp malf/fail
- BOEING 737 7H4 · SOUTHWEST AIRLINES COPhiladelphia, PAPowerplant sys/comp malf/fail
- BOEING 737-700 · Southwest AirlinesPensacola, FLPowerplant sys/comp malf/fail
- BOEING 757 · DELTA AIR LINES INCLas Vegas, NVPowerplant sys/comp malf/fail
- BOMBARDIER INC CL 600 2B19 · Endeavor AirBaltimore, MDPowerplant sys/comp malf/fail
- AIRBUS A319 132 · Spirit AirlinesGreenville, TXPowerplant sys/comp malf/fail
- MCDONNELL DOUGLAS MD-10-30F · FEDERAL EXPRESS CORPORATIONPortland, ORPowerplant 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
- 8 of 8Aircraft › Aircraft power plant › Engine (turbine/turboprop)
- 2 of 8Organizational issues › Development › Design
- 2 of 8Aircraft › Aircraft structures › Nacelles/pylons structure
Occurrences it coded
- 8 of 8Powerplant sys/comp malf/fail
- 2 of 8Engine shutdown
Set against the Board’s own findings for this case
Cited here, and common in the precedents
- —
Cited here, not seen in the precedents
- Support/oversight/monitoring › Training
Common in the precedents, not cited here
- Aircraft power plant › Engine (turbine/turboprop)
- Aircraft structures › Nacelles/pylons structure
- Development › Design
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
- 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.
- 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…
- DCA18MA1422018-04-17 · BOEING 737 7H4 · SOUTHWEST AIRLINES CO
A low-cycle fatigue crack in the dovetail of fan blade No. 13, which resulted in the fan blade separating in flight and impacting the engine fan case at a location that was critical to the structural integrity and performance of the fan cowl structure. This impact led to the in-flight separation of fan cowl components, including the inboard fan cowl aft latch keeper, which struck the fuselage near a cabin window and caused the window to depart from the airplane, the cabin to rapidly depressurize, and the passenger…
- 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.
- 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…
What it recommended after them
- A-19-017TO THE FEDERAL AVIATION ADMINISTRATION: Require Boeing to determine the critical fan blade impact location(s) on the CFM56-7B engine fan case and redesign the fan cowl structure on all Boeing 737 next-generation-series airplanes to ensure t… · DCA18MA142Closed - Acceptable Action
- A-19-018TO THE FEDERAL AVIATION ADMINISTRATION: Once the actions requested in Safety Recommendation A-19-17 are completed, require Boeing to install the redesigned fan cowl structure on new-production 737 next-generation-series airplanes. · DCA18MA142Open - Acceptable Response
- A-19-019TO THE FEDERAL AVIATION ADMINISTRATION: Once the actions requested in Safety Recommendation A-19-17 are completed, require operators of Boeing 737 next-generation-series airplanes to retrofit their airplanes with the redesigned fan cowl str… · DCA18MA142Open - Acceptable Response
- A-19-020TO THE FEDERAL AVIATION ADMINISTRATION: Expand the Title 14 Code of Federal Regulations Part 25 and 33 certification requirements to mandate that airplane and engine manufacturers work collaboratively to (1) analyze all critical fan blade i… · DCA18MA142Open - Acceptable Response
- A-19-021TO THE FEDERAL AVIATION ADMINISTRATION: Develop and issue guidance on ways that air carriers can mitigate hazards to passengers affected by an in-flight loss of seating capacity. · DCA18MA142Closed - Unacceptable Action
- A-19-022TO SOUTHWEST AIRLINES: Include the lessons learned from the accident involving Southwest Airlines flight 1380 in initial and recurrent flight attendant training, emphasizing the importance of being secured in a jumpseat during emergency lan… · DCA18MA142Closed - Acceptable Action
- A-19-023TO THE EUROPEAN AVIATION SAFETY AGENCY: Expand your certification requirements for transport-category airplanes and aircraft engines to mandate that airplane and engine manufacturers work collaboratively to (1) analyze all critical fan blad… · DCA18MA142Open - Acceptable Response
- 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
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).