American Airlines Flight 304
Boeing 757-223 · Accident: in flight encounter with weather en route
From Dallas Fort Worth International Airport (DFW) to Luis Munoz Marin International Airport (SJU)
Event
- NTSB case
- FTW00LA244
- 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
- 0
- 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
- Instrument Meteorological Cond
Boeing 757-223
- Aircraft type
- Boeing 757
- 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
- N657AM
- Operator
- American Airlines
- Onboard fatalities
- Unknown
- Route
- From Dallas Fort Worth International Airport (DFW), DALLAS/FT WORTH, TXTo Luis Munoz Marin International Airport (SJU), San Juan, PR
- Aircraft age
- Not recorded
- 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 121: Air Carrier
- 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
- En route · cruise
- First occurrenceThe 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
- In flight encounter with weather
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Minor
Cause areas
- Flightcrew › Flight into adverse weather, inadvertent
Not plotted · Location withheld: coordinates are missing, conflicting, invalid, or have no accepted acquisition method. No substitute location has been invented.
NTSB narrative
During cruise flight at 37,000 feet over the Gulf of Mexico, the scheduled international passenger flight encountered severe turbulence after inadvertently penetrating rapidly developing convective formations. One of the flight attendants was seriously injured. When the turbulence encounter occurred, the flight crew was attempting to deviate around cloud formations. The flight crew reported that the seat belt sign was illuminated prior to the turbulence encounter and that the captain made an announcement to the passengers reminding them to remain seated with their seatbelts secured. It is unknown whether the flight attendant was seated or standing, or where she was positioned at the time of the event. Following the turbulence encounter, the flight diverted to a nearby airport and landed without further incident.
Probable cause
the flight crew's inadvertent encounter with convective turbulence while in cruise flight. A factor was the rapidly developing convective activity.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record FTW00LA244
- Event ID
- 20001212X21738
- Case number
- FTW00LA244
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (5)
- 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. 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: c6de6a0ad50d8d17b5d21a447fadb7e67787a645ab9943ae0bb8d17d9cbf883a; retrieved 2026-09-18T16:28:08.215Z.
- The NTSB's operator name is blank for N657AM; the operator shown is the name the NTSB records it doing business as.