Air Canada Flight 680
McDonnell Douglas DC9 32 · Accident
From Boston Logan International Airport (BOS) to Yarmouth
Event
- NTSB case
- NYC79AA106
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- Airline
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
McDonnell Douglas DC9 32
- Aircraft type
- McDonnell Douglas DC9
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- CF-TLU
- Operator
- Air Canada
- Onboard fatalities
- Unknown
- Route
- From Boston Logan International Airport (BOS), Boston, MATo Yarmouth
- Aircraft age
- About 11 years (built 1968)
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 129: Foreign
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Not recorded
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Not recorded
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Aircraft › Aircraft structures
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The Safety Board's full report is available at http://www.ntsb.gov/investigations/AccidentReports/Pages/aviation.aspx. The Aircraft Accident Report number is NTSB/AAR-80-13.
At 1212 EDT, on September 17, 1979, Air Canada Flight 680, a scheduled passenger flight to Yarmouth, Nova Scotia, Canada, departed Logan International Airport, Boston, Massachusetts. About 14 min after takeoff, at an altitude of about 25,000 ft msl, the tailcone along with the aft cabin pressure access door and a portion of the aft cabin pressure bulkhead separated from the aircraft causing rapid decompression of the passenger and flightcrew compartments. The aircraft was landed safely at Logan International Airport about 38 min after takeoff. Of the 45 persons aboard, one flight attendant received minor injuries during the decompression. The aircraft's oxygen system and its elevator control and engine control systems were damaged.
Probable cause
a fatigue fracture of the aft cabin pressure bulkhead which resulted in a rapid decompression of the aircraft's cabin area. This fracture initiated from a crack below the aft bulkhead access door which was discernible on the X-rays taken during the aircraft's last maintenance inspection but was not detected by the inspectors.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record NYC79AA106
- Event ID
- 20170710X52551
- Case number
- NYC79AA106
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status, coordinates. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 7eb2293c64e531d59912e5b854e088f2aa88915e9398917c72ea87e767ab1982; retrieved 2026-09-18T21:13:36.522Z.