BOEING 737-9 near Portland, OR — 2024-01-06

Probable cause

the in-flight separation of the left mid exit door (MED) plug due to Boeing Commercial Airplanes’ failure to provide adequate training, guidance, and oversight necessary to ensure that manufacturing personnel could consistently and correctly comply with its parts removal process, which was intended to document and ensure that the securing bolts and hardware that were removed from the left MED plug to facilitate rework during the manufacturing process were reinstalled. Contributing to the accident was the Federal Aviation Administration’s ineffective compliance enforcement surveillance and audit planning activities, which failed to adequately identify and ensure that Boeing addressed the repetitive and systemic nonconformance issues associated with its parts removal process.

Contributing factors

Contributing to the accident was the Federal Aviation Administration’s ineffective compliance enforcement surveillance and audit planning activities, which failed to adequately identify and ensure that Boeing addressed the repetitive and systemic nonconformance issues associated with its parts removal process.

NTSB narrative

On January 5, 2024, about 1713 Pacific standard time, Alaska Airlines flight 1282, a Boeing 737-9 airplane, N704AL, experienced an in-flight separation of the left mid exit door plug and rapid depressurization during climb after takeoff from Portland International Airport, Portland, Oregon. One flight attendant and 7 passengers received minor injuries; the captain, the first officer, 3 flight attendants, and 164 passengers were uninjured; and the airplane sustained substantial damage. The scheduled domestic passenger flight was operated under Title 14 Code of Federal Regulations Part 121 and departed PDX about 1707 with a planned destination of Ontario International Airport, Ontario, California.

NTSB coding

• Part(s) separation from AC · Enroute-climb to cruise

Evidence available

• CVR
• Video
• FDR / data
• Photos
• 102 docket documents

Docket documentsshowing 50 of 102

• 12 COCKPIT VOICE RECORDER - SPECIALIST'S FACTUAL REPORTcvr
• 10-A FLIGHT DATA RECORDER - SPECIALIST'S FACTUAL REPORTfdr
• 10-B FLIGHT DATA RECORDER - SPECIALIST'S FACTUAL REPORT - ATTACHMENT1 - FDR TABULAR DATAfdr
• 10-C FLIGHT DATA RECORDER - SPECIALIST'S FACTUAL REPORT - ATTACHMENT2 - QAR TABULAR DATAfdr
• 10-D FLIGHT DATA RECORDER - SPECIALIST'S FACTUAL REPORT - ATTACHMENT3 - FDR TABULAR DATAfdr
• 10-E FLIGHT DATA RECORDER - SPECIALIST'S FACTUAL REPORT - ATTACHMENT4 - QAR TABULAR DATAfdr
• 10-F FLIGHT DATA RECORDER - SPECIALIST'S FACTUAL REPORT - ATTACHMENT5 - FDR TABULAR DATAfdr
• 10-G FLIGHT DATA RECORDER - SPECIALIST'S FACTUAL REPORT - ATTACHMENT6 - QAR TABULAR DATAfdr
• 11-A MANUFACTURING RECORDS AND HUMAN PERFORMANCE FACTUAL REPORTform
• 11-B MANUFACTURING RECORDS AND HUMAN PERFORMANCE ATTACHMENT 1 - NCR N1450292531 AND NCO 145-8789-RSHK-1296-002NCform
• 11-C MANUFACTURING RECORDS AND HUMAN PERFORMANCE ATTACHMENT 2 - NCR N1450293199 AND NCO 145-8789-RGEN-RSHK-001NCform
• 11-E MANUFACTURING RECORDS AND HUMAN PERFORMANCE ATTACHMENT 4 - PREVIOUS MED PLUG REMOVALSform
• 11-F MANUFACTURING RECORDS AND HUMAN PERFORMANCE ATTACHMENT 5 - BOEING QUALITY ALERT 2023-0056-ARform
• 11-G MANUFACTURING RECORDS AND HUMAN PERFORMANCE ATTACHMENT 6 - BCA QMS DOCUMENT CONTROL EXCERPTform
• 11-H MANUFACTURING RECORDS AND HUMAN PERFORMANCE ATTACHMENT 7 - BCA QMS SUPPLIER CONTROL EXCERPTform
• 11-I MANUFACTURING RECORDS AND HUMAN PERFORMANCE ATTACHMENT 8 - BCA QMS QUALITY ESCAPES EXCERPTform
• 11-J MANUFACTURING RECORDS AND HUMAN PERFORMANCE ATTACHMENT 9 - BOEING SAFETY ACTIONSform
• 11-M MANUFACTURING RECORDS AND HUMAN PERFORMANCE - ATTACHMENT 12 FAA INTERVIEWS REDACTEDform
• 11-Q EXCERPTS FROM BOEING PROCESS INSTRUCTION - PERFORM PRODUCT CONFORMANCEform
• 11-W BOEING REQUEST - FACTUAL INFORMATIONform
• 2-L OPERATIONAL FACTORS - ATTACHMENT 11 - BOEING RESPONSE TO FLIGHT DECK DOOR INFORMATION REQUESTform
• MANUFACTURING RECORDS AND HUMAN PERFORMANCE FACTUAL REPORT ADDENDUMform
• STATEMENT OF PARTY REPRESENTATIVES TO NTSB INVESTIGATION - ADDITIONAL PARTY FORM NO. 2form
• STATEMENT OF PARTY REPRESENTATIVES TO NTSB INVESTIGATION - ADDITIONAL PARTY FORMS NO. 1form
• STATEMENT OF PARTY REPRESENTATIVES TO NTSB INVESTIGATION - PARTY FORM NO. 3form
• STATEMENT OF PARTY REPRESENTATIVES TO NTSB INVESTIGATION - PARTY FORM NO. 4form
• SYSTEMS GROUP - PARTY REPRESENTATIVE FORMSform
• 1-F STATEMENT OF PURPOSEinterview
• 6-C SURVIVAL FACTORS - ATTACHMENT 2 PASSENGER INTERVIEW SUMMARIESinterview
• PRESENTATION - IIC OPENING STATEMENTinterview
• 1-A ORDER OF HEARINGother
• 1-B DESIGNATION OF CHAIR OF BOARD OF INQUIRYother
• 1-C DESIGNATION OF HEARING OFFICERother
• 1-D DESIGNATION OF PARTIES TO THE HEARINGother
• 1-E NOTICE OF INVESTIGATIVE HEARINGother
• 1-G WITNESS LISTother
• 1-H WITNESSES PROFESSIONAL BIOGRAPHIESother
• 1-I EXHIBIT LISTother
• 1-J BOARD OF INQUIRY AND TECHNICAL PANEL PROFESSIONAL BIOGRAPHIESother
• 11-O EXCERPTS FROM BOEING PROCESS INSTRUCTION 1581other
• 11-P EXCERPTS FROM BOEING PROCESS INSTRUCTION - APPLY AUTHORITY MEDIA IN THE COMMON MANUFACTURING EXECUTION SYSTEMother
• 11-S BOEING INSTALLATION PLAN - INSTALLATION OF INSULATION BLANKETS SEC 46 - LEFTother
• 11-T BOEING INSTALLATION PLAN - INSTALLATION OF INSULATION BLANKETS SEC 46 - RIGHTother
• 11-U EXCERPTS FROM BOEING MID EXIT DOOR PLUG RIGGING DRAWINGother
• 11-V BOEING PROCESS INSTRUCTION 1581 DOCUMENT CHANGE HISTORY OVERVIEW- 2013-2023 EXCERPTSother
• 15-B MATERIALS GROUP CHAIR'S APPENDIX Aother
• 2-D OPERATIONAL FACTORS - ATTACHMENT 3 - FLIGHT CREW TRAINING RECORDSother
• 2-D OPERATIONAL FACTORS - ATTACHMENT 3 - FLIGHT CREW TRAINING RECORDS - FLIGHT CREW NAMES REDACTEDother
• 2-E OPERATIONAL FACTORS -ATTACHMENT 4 - ALASKA AIRLINES CHECKLISTother
• 2-F OPERATIONAL FACTORS - ATTACHMENT 5 - SIMULATOR EVALUATIONother

Related mishaps

• DAVIS DAN B LANCAIR EVOLUTION

  2021-03-18 · Phoenix, AZ

• Bell 430

  2018-10-27 · Kailua, HI

• ISRAEL AIRCRAFT INDUSTRIES GULFSTREAM 200

  2014-01-14 · Savannah, GA

• WHEELER VANS RV-6A

  2011-08-28 · Albany, OR

• BEECH E-90

  2011-02-15 · Des Moines, IA

• BEECH 300

  2010-12-10 · Minneapolis, MN