# NTSB DCA23LA172: Boeing 777, N212UA, Kahului, HI, December 19, 2022

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Class 4 · Limited · Final report
- Date: December 18, 2022, 14:51 local (Dec 19, 2022, 00:51 UTC)
- Place: Kahului, HI · departure airport
- Coordinates: 20.898649, -156.43045 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=20.8986&lon=-156.4305&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Defining event: [Enroute-climb to cruise: Altitude deviation](https://openairdocs.org/ntsb-events/282)
- Highest injury: No injuries
- Injuries: 281 uninjured
- Status: Completed
- Report: Approved by Office Director
- Investigation class: Class 4 - Basic report with no Prelim publish
- NTSB office: Major Investigations Division
- Parties: FAA/AVP-100
- NTSB case key (mKey): 106734
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DCA23LA172
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/106734/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=106734
- Page: https://openairdocs.org/ntsb/DCA23LA172

## Probable cause

The flight crew’s failure to manage the airplane’s vertical flightpath, airspeed, and pitch attitude following a miscommunication about the captain’s desired flap setting during the initial climb.

## Findings

NTSB's coded findings; those marked are part of the probable cause.

- [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Boeing 777-222, 1 case](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=1385219), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md)
- [Info processing/decision: identification/recognition](https://openairdocs.org/ntsb-findings/02041510): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Boeing 777-222, 1 case](https://openairdocs.org/ntsb-findings/02041510/cases.md?model=1385219), [All aircraft, 559 cases](https://openairdocs.org/ntsb-findings/02041510/cases.md)

## Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event best describes what happened.

- [Enroute-climb to cruise: Altitude deviation](https://openairdocs.org/ntsb-events/282) (defining event); cases with it: [Boeing 777-222, 1 case](https://openairdocs.org/ntsb-events/282/sequence.md?model=1385219), [All aircraft, 104 cases](https://openairdocs.org/ntsb-events/282/sequence.md)

## Analysis

United flight 1722 lost altitude about 1 minute after departure while in instrument meteorological conditions, which included heavy rain. The airplane descended from 2,100 ft to about 748 ft above the water before the crew recovered from the descent. No injuries were reported, and the airplane was not damaged. The NTSB was not originally notified of the event, since it did not meet the requirements of Title 49 Code of Federal Regulations Part 830.5. However, the NTSB learned of the event about 2 months later and chose to open an investigation. By that time, both the cockpit voice and flight data recorder durations had been exceeded. The investigation utilized flight crew statements and other records as information sources. The captain (who was the pilot flying) reported that he and the first officer had initially planned for a flaps-20 takeoff (flap setting of 20°) with a reduced-thrust setting, based on performance calculations. However, during taxi, the ground controller advised them that low-level windshear advisories were in effect. Based on this information, the captain chose a flaps-20 maximum thrust takeoff instead. He hand-flew the takeoff, with the auto throttles engaged. During the takeoff, the rotation and initial climb were normal; however, as the airplane continued to climb, the flight crew noted airspeed fluctuations as the airplane encountered turbulence. When the airplane reached the acceleration altitude, the captain reduced the pitch attitude slightly and called for the flap setting to be reduced to flaps 5. According to the first officer, he thought that he heard the captain announce flaps 15, which the first officer selected before contacting the departure controller and discussing the weather conditions. The captain noticed that the maximum operating speed indicator moved to a lower value than expected, and the airspeed began to accelerate rapidly. The captain reduced the engine thrust manually, overriding the auto throttle servos, to avoid a flap overspeed and began to diagnose the flap condition. He noticed that the flap indicator was showing 15°, and he again called for flaps 5, and he confirmed that the first officer moved the flap handle to the 5° position. The first officer stated that he “knew the captain was having difficulty with airspeed control”, and he queried the captain about it as he considered if his own (right side) instrumentation may have been in error. He did not receive an immediate response from the captain. Both pilots recalled that, about this time, the airplane’s pitch attitude was decreasing, and the airspeed was increasing. The first officer recalled that that the captain asked for flaps 1 soon after he had called for flaps 5, and when the first officer set the flaps to 1°, he then noticed the airspeed had increased further, and the control column moved forward. Both pilots recalled hearing the initial warnings from the ground proximity warning system (GPWS), and the first officer recalledannouncing “pull up pull up” along with those initial GPWS warnings. The captain then pulled aft on the control column, initially reduced power to reduce airspeed, and then applied full power to “begin the full CFIT [controlled flight into terrain] recovery.” The first officer recalled that, as the captain was performing the recovery, the GPWS alerted again as the descent began to reverse trend; data showed this occurred about 748 ft above the water. After noting a positive rate of climb, the captain lowered the nose to resume a normal profile, ensured that the flaps and speed brakes were fully retracted, and engaged the autopilot. The remainder of the flight was uneventful. Figure 1 shows a perspective view of the flight track. Figure 1- Flight Track with Annotations As a result of the event, United Airlines modified one of their operations training modules to address this occurrence and issued an awareness campaign about flight path management at their training center.

## Aircraft

- Registration: [N212UA](https://openairdocs.org/aircraft/N212UA), registered now, S/N 30218, built 2000 (OpenAirDocs)
- Reported make and model: BOEING 777 (222)
- Registry model: [Boeing 777-222](https://openairdocs.org/model/boeing-777-222) (registry code 1385219) (OpenAirDocs)
- Registry engine: [Pratt & Whitney PW4000 series](https://openairdocs.org/engine/pratt-whitney-pw4000-series) (registry code 52119, turbo-fan) (OpenAirDocs)
- Category: Airplane
- Serial number: 30218
- Year built: 2000
- Airframe hours: 74017
- Engines: P&W PW4077 60000 lbs thrust turbo jet; P&W PW4077 60000 lbs thrust turbo jet
- Damage: No damage
- Flight: Part 121
- Operator: United Airlines Inc
- Registered owner: United Airlines Inc
- Airworthiness certificate: Standard, Transport
- Last inspection: Continuous airworthiness, August 14, 2021
- Departed: OGG, Kahului, HI
- Destination: SFO, San Francisco, CA
- Flight plan: IFR
- Equipment: Stall warning system, Satellite tracking device, ADS-B, Onboard weather, 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 55; injuries: none; flight engineer, airline transport, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review April 8, 2022; seat: left; restraint: 5-point; flight hours: 19,600 total, 5,000 in this make and model, 10,900 as pilot in command, 100 in the last 90 days, 30 in the last 30 days
- Co-pilot; injuries: none; airline transport, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review February 7, 2023; seat: right; restraint: 5-point; flight hours: 5,300 total, 120 in this make and model, 2,395 as pilot in command, 120 in the last 90 days, 30 in the last 30 days, 5 in the last 24 hours

## Weather

- Conditions: Instrument (IMC), Day
- Wind: 140° at 10 knots
- Visibility: 3 statute miles
- Lowest ceiling: 900 ft broken
- Temperature: 66 °F, dew point 64 °F
- Altimeter: 29.78 inHg
- Turbulence: Unknown
- Observed at: PHOG
- METAR: PHOG 190050Z 14010KT 3SM +RA BR BKN009 OVC020 19/18 A2978 190 93 800 130/10 RMK AO2 SLP088 P0018 T01940183

## Docket (6 files)

The files NTSB released with the investigation on August 10, 2023, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=106734. 9.6 MB in all.

- Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 6.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15932697&FileExtension=pdf&FileName=01-01%20-%20NTSB%206120%20DCA23LA172_print2-Rel.pdf
- Flight crew statements (item 2, PDF, 4 pages, 133 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15933260&FileExtension=pdf&FileName=01-02%20Pilot%20Statements_V2_Redacted-Rel.pdf
- Memorandum for record - flight information provided by operator (item 3, PDF, 4 pages, 348 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15609325&FileExtension=pdf&FileName=01-04%20%20MFR%20-%20Information%20provided%20by%20UAL-Rel.pdf
- Weather reports and records (item 4, PDF, 6 pages, 731 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15608927&FileExtension=pdf&FileName=04-01%20%20MFR%20-%20Weather%20Reports%20and%20Records-Rel.pdf
- ADS-B data - graphical (item 5, PDF, 2 pages, 590 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15609449&FileExtension=pdf&FileName=05-01%20%20MFR%20-%20ADS-B%20Data%20-%20Graphical-Rel.pdf
- ADS-B data - tabular (item 6, CSV, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15608994&FileExtension=csv&FileName=05-02%20-%20ADS-B%20Tabular%20Data-Rel.csv

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.