OPS12IA849 · Unknown aircraft
Incident: air traffic event on approach
Event
- NTSB case
- OPS12IA849
- 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
- Event fatalities
- Unknown
- 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
- Unknown
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Not recorded
Unknown aircraft
- 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
- Unknown
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From not recordedTo not recorded
- 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
- Unknown
- 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
- Approach
- 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
- Air traffic event
- 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
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The airport had been using runway 1 for arrivals and departures all day. Because of thunderstorms south of the airport, the approach control area supervisor for Mount Vernon (MTV) attempted to coordinate with the airport tower supervisor to stop departures from runway 1 and temporarily land arrivals on runway 19, opposite to the traffic flow in use. According to the airport’s standard operating procedures, requests for runway changes must be approved by a tower supervisor, but the tower supervisor was unable to take the call because he was on a different phone line and distracted by administrative duties. Instead, a traffic management coordinator took the coordination call. A misunderstanding occurred between the MTV supervisor and the traffic management coordinator. The coordinator stated that she had missed the supervisor's reference to use of runway 19, and instead thought arrivals would be continuing to use runway 1, only with reduced spacing. The coordinator relayed the incorrect information to the local controllers responsible for the runways. The local controllers subsequently released two departures from runway 1 and both flights lost required separation with the first arriving airplane inbound from the northwest to land on runway 19.
Probable cause
A hearback/readback error on the part of the tower traffic management coordinator, who did not understand the request being made by the approach control area supervisor and then communicated that misunderstanding to the local controllers. Contributing to the incident was the lack of standard coordination procedures between the tower and approach control for temporary runway changes and the accepted practice of operations supervisors being distracted by non-operational duties while responsible for tower operations and interfacility coordination.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record OPS12IA849
- Event ID
- 20120802X64749
- Case number
- OPS12IA849
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
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: b92d6fd8a58304b1b8824759ebffa4d3a73fd0e99dab18b2dec0a3b84eebd641; retrieved 2026-09-15T19:12:18.815Z.