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NTSB Report
May 30, 1987 · Mcdonnell Douglas DC-9-82 · N224AA
Chicago, IL
Overview
Report Status
Preliminary report
Event Type
Incident
Date
May 30, 1987
Injury Outcomes
No injuries (83 uninjured)
Location
Chicago, IL
Aircraft
Mcdonnell Douglas DC-9-82
Tail Number
N224AA
Injuries
None
NTSB Number
CHI87IA135
AMERICAN FLT 637 WAS ON DEPARTURE FROM CHICAGO-O'HARE INTL ARPT (ORD), CLIMBING THRU 7300' MSL, WHEN IT PASSED AMERICAN FLT 393 WITH APRX 500' VERTICAL SEPN & 1/4 MI HORIZONTAL SEPN. THIS OCCURRED AFTER AN AIR TRAFFIC ASSISTANT, WHO WAS WORKING THE CLNC DELIVERY PSN AT ORD, HAD ISSUED THE SAME TRANSPONDER CODE TO FLT 637 & UNITED FLT 441. SUBSEQUENTLY, A TRAINEE CONTROLLER (CTLR), WHO WAS WORKING AT THE WEST DEPARTURE RADAR CONTROL POSITION, MISTOOK FLT 441'S TARGET AS THAT OF FLT 637 & ISSUED CLIMB INSTRUCTIONS TO FLT 637. THE INSTRUCTOR DID NOT RECOGNIZE THE ERROR IN TIME TO CORRECT THE CTLR'S ACTION.
Full Narrative
AMERICAN FLT 637 WAS ON DEPARTURE FROM CHICAGO-O'HARE INTL ARPT (ORD), CLIMBING THRU 7300' MSL, WHEN IT PASSED AMERICAN FLT 393 WITH APRX 500' VERTICAL SEPN & 1/4 MI HORIZONTAL SEPN. THIS OCCURRED AFTER AN AIR TRAFFIC ASSISTANT, WHO WAS WORKING THE CLNC DELIVERY PSN AT ORD, HAD ISSUED THE SAME TRANSPONDER CODE TO FLT 637 & UNITED FLT 441. SUBSEQUENTLY, A TRAINEE CONTROLLER (CTLR), WHO WAS WORKING AT THE WEST DEPARTURE RADAR CONTROL POSITION, MISTOOK FLT 441'S TARGET AS THAT OF FLT 637 & ISSUED CLIMB INSTRUCTIONS TO FLT 637. THE INSTRUCTOR DID NOT RECOGNIZE THE ERROR IN TIME TO CORRECT THE CTLR'S ACTION.
Flight
Event TypeIncident
Event Time19:58 CDT
Nearest Airport0nm N
Runway0
Runway Length0
Runway Width0
Flight Plan FiledIFR
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftMcdonnell Douglas DC-9-82
Tail NumberN224AA
Aircraft CategoryAir
Operating RulePart 121
Engines2
Engine TypeTurbofan
Engine DetailsP&W · JT8D · Turbofan · 20850
Seats172
People & Injuries
Injury SummaryNo injuries (83 uninjured)
Fatal0
Serious0
Minor0
Uninjured83
Total83
Crew 1Age 39 · First Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
Visibility15 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter29.00 inHg
Observation Time19:58
Weather SourceWIT