# NTSB DEN89IA089: Boeing 727-200A, N728, San Antonio, TX, March 22, 1989

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Incident investigation · Final report
- Date: March 21, 1989, 18:29 local (Mar 22, 1989, 00:29 UTC)
- Place: San Antonio, TX
- Location: 29.4241° N, 98.4936° W: Placed by OpenAirDocs: center of San Antonio, TX, within about 13 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=29.4241&lon=-98.4936&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 261 uninjured
- Status: Completed, report September 30, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 17617
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN89IA089
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/17617/pdf
- Page: https://openairdocs.org/ntsb/DEN89IA089

## Probable cause (aircraft 2)

FAILURE OF THE ARTCC CONTROLLER TO ASSURE THAT THE AIRCRAFT MAINTAINED IFR SEPARATION STANDARDS.  THE CONTROLLER'S HEAVY WORKLOAD WAS A RELATED FACTOR.

## Probable cause (aircraft 1)

FAILURE OF THE ARTCC CONTROLLER TO ASSURE THAT THE AIRCRAFT MAINTAINED IFR SEPARATION STANDARDS.  THE CONTROLLER'S HEAVY WORKLOAD WAS A RELATED FACTOR.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Near collision between aircraft, cruise
  - ifr separation standards - not maintained, atc personnel(artcc) (cause)
  - excessive workload (task overload), atc personnel(artcc) (contributing factor)
- Near collision between aircraft, cruise
  - ifr separation standards - not maintained, atc personnel(artcc) (cause)
  - excessive workload (task overload), atc personnel(artcc) (contributing factor)

## Analysis (aircraft 2)

AMERICAN AIRLINE FLT 1269 & MEXICANA AIRLINE FLT 731 WERE CRUISING AT FL 290 ON SOUTHERLY HEADINGS. AFTER DEVIATING AROUND WEATHER, FLT 1269 WAS ON A SOUTH-SOUTHEASTERLY HEADING. SUBSEQUENTLY, THE TWO BOEING 727 AIRCRAFT CONVERGED TO ABOUT 1.06 MI FROM EACH OTHER, VIOLATING THE MINIMUM HORIZONTAL SEPARATION REQUIREMENT. THE OPERATIONAL ERROR OCCURRED WHEN THE ARTCC CONTROLLER WAS BUSY WITH HEAVY TRAFFIC.

## Analysis (aircraft 1)

AMERICAN AIRLINE FLT 1269 & MEXICANA AIRLINE FLT 731 WERE CRUISING AT FL 290 ON SOUTHERLY HEADINGS.  AFTER DEVIATING AROUND WEATHER, FLT 1269 WAS ON A SOUTH-SOUTHEASTERLY HEADING.  SUBSEQUENTLY, THE TWO BOEING 727 AIRCRAFT CONVERGED TO ABOUT 1.06 MI FROM EACH OTHER, VIOLATING THE MINIMUM HORIZONTAL SEPARATION REQUIREMENT.  THE OPERATIONAL ERROR OCCURRED WHEN THE ARTCC CONTROLLER WAS BUSY WITH HEAVY TRAFFIC.

## Aircraft 1

- Registration: N728 (not matched to a registry record)
- Reported make and model: BOEING 727-200A
- Category: Airplane
- Engines: P&W JT8D-9 14000 lbs thrust turbo fan
- Damage: No damage
- Flight: Part 121
- Operator: American Airlines
- Registered owner: American Airlines
- Airworthiness certificate: Standard, Transport
- Departed: DFW, DALLAS, TX
- Destination: CUN, CAN CUN
- Flight plan: IFR

## Aircraft 2

- Registration: XAMXE (not matched to a registry record)
- Reported make and model: BOEING 727-200
- Category: Airplane
- Engines: P&W JT8D-17R 17000 lbs thrust turbo fan
- Damage: No damage
- Flight: Part 129
- Operator: Mexicana Airlines
- Registered owner: Mexicana Airlines
- Airworthiness certificate: Standard, Transport
- Departed: DFW, DALLAS, TX
- Destination: MTY, MARIANO ESCOBED
- Flight plan: IFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot, aircraft N728; age 51; airline transport; airplane ratings: multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; seat: left; flight hours: 16,000 total, 6,000 in this make and model, 180 in the last 90 days, 5 in the last 24 hours
- Pilot, aircraft 2; age 32; airline transport; airplane ratings: multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 6,300 total, 5,300 in this make and model, 730 as pilot in command, 150 in the last 90 days, 50 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Night/dark
- Observed at: HOU

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.