2 large transport in conflict approaching mex at 16000' MSL.

Attributes
ACN	145744
Time
Date	199005
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : mex
State Reference	FO
Altitude	msl bound lower : 15000 msl bound upper : 16000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : mex
Operator	common carrier : air carrier
Make Model Name	Large Transport
Flight Phase	cruise other descent other
Route In Use	arrival other enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other descent other
Route In Use	arrival other enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : commercial pilot : instrument pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 180 flight time total : 12000 flight time type : 6000
ASRS Report	145744
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 190 flight time total : 5500 flight time type : 1000
ASRS Report	145666
Events
Anomaly	conflict : airborne less severe
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action other
Consequence	Other
Miss Distance	horizontal : 2000 vertical : 800
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

On arrival into mex at 16000' MSL and cleared to san mateo VOR and approach to 5L, another large transport was sighted at 10 O'clock position, 1 mi and closing. An immediate turn and descent to 15000' was initiated by me and averted a very close cal. I believe this was a controller mistake brought on by another aircraft with a low fuel state being vectored in front of both of us. The controller thought that 1 of us was at 15000'. There may have been a language problem but both aircraft had been assigned 16000' by mex. I believe good vigilance and eyes outside averted a near disaster.

Original NASA ASRS Text

Title: 2 LGT IN CONFLICT APCHING MEX AT 16000' MSL.

Narrative: ON ARR INTO MEX AT 16000' MSL AND CLRED TO SAN MATEO VOR AND APCH TO 5L, ANOTHER LGT WAS SIGHTED AT 10 O'CLOCK POS, 1 MI AND CLOSING. AN IMMEDIATE TURN AND DSNT TO 15000' WAS INITIATED BY ME AND AVERTED A VERY CLOSE CAL. I BELIEVE THIS WAS A CTLR MISTAKE BROUGHT ON BY ANOTHER ACFT WITH A LOW FUEL STATE BEING VECTORED IN FRONT OF BOTH OF US. THE CTLR THOUGHT THAT 1 OF US WAS AT 15000'. THERE MAY HAVE BEEN A LANGUAGE PROB BUT BOTH ACFT HAD BEEN ASSIGNED 16000' BY MEX. I BELIEVE GOOD VIGILANCE AND EYES OUTSIDE AVERTED A NEAR DISASTER.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.