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Trans World Airlines Boeing 767-231 incident

5 Sept 1989 · Knox, IN, United States

Boeing 767-231 · Incident: near collision between aircraft en route

From St. Louis Lambert International Airport (STL) to Paris, FRANCE

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Event

NTSB case
CHI89IA179
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
Incident
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 767-231

Aircraft type
Boeing 767
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
N608TW
Onboard fatalities
Unknown
Route
From St. Louis Lambert International Airport (STL), ST LOUIS, MOTo Paris, FRANCE
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
Near collision between aircraft
DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
None

Cause areas

  • Atc personnel(artcc) › Radar separation, not maintained

Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.

NTSB narrative

THIS AIRPLANE WAS INVOLVED IN A NEAR COLLISION WITH ANOTHER AIRPLANE WHILE IN POSITIVE CONTROL AIRSPACE. BOTH AIRPLANES TOOK EVASIVE ACTION. VISIBILITY WAS REPORTED BY BOTH FLIGHT CREWS AS BEING REDUCED BY THE PRESENCE OF CIRRUS CLOUDS WITH NO VISIBLE HORIZON. THIS AIRPLANE HAD ACKNOWLEDGED AND RESPONDED TO A TURN INSTRUCTION ISSUED TO A THIRD AIRPLANE WITH A SIMILAR CALL SIGN, AND TURNED TO A HEADING WHICH PUT THE TWO INVOLVED AIRPLANES ON AN INTERSECTING COURSE. THE TURN INSTRUCTION WAS CHALLENGED BY THE AIRPLANE FOR WHOM IT WAS INTENDED, BUT THE INCIDENT AIRPLANE WAS NEVER TURNED BACK TO ITS ORIGINAL HEADING. THE ERROR WAS DISCOVERED A SHORT TIME LATER BY THE MANUAL CONTROLLER AND POINTED OUT TO THE RADAR CONTROLLER. HE ISSUED TURN AND CLIMB INSTRUCTIONS TO THE INCIDENT AIRPLANE ALONG WITH A TRAFFIC ADVISORY. CORRELATION OF THE TWO DFDR READOUTS WITH RADAR TRACK DATA SHOW, THAT AT THE POINT OF CLOSEST APPROACH, VERTICAL SEPARATION WAS BETWEEN 95 AND 200 FT.

Probable cause

THE RADAR CONTROLLLER'S FAILURE TO MAINTAIN RADAR SEPARATION. FACTORS CONTRIBUTING TO THE INCIDENT WERE: MISUNDERSTANDING OF AN ATC INSTRUCTION BY THE PILOT OF THE INCIDENT AIRPLANE, AND UNCLEAR PHRASEOLOGY USED IN THE INSTRUCTIONS ISSUED BY THE RADAR CONTROLLER.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record CHI89IA179
Event ID
20001213X29317
Case number
CHI89IA179
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, damage. 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: 542cce144e6fb6421a4dc0c807d1cb9f5a063fcb4348122877d579bbcad540cb; retrieved 2026-09-18T19:08:40.585Z.