Possible less than standard separation between air carrier X and air carrier Y. Possible system erro...

Attributes
ACN	156370
Time
Date	199009
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : mdw
State Reference	IL
Altitude	msl bound lower : 3000 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : ord
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	climbout : intermediate altitude
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time total : 15400
ASRS Report	156370
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 5200 flight time type : 800
ASRS Report	156699
Events
Anomaly	conflict : airborne less severe
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Miss Distance	horizontal : 18000 vertical : 0
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other

Narrative:

Air carrier X departed runway 4R at mdw heading 090 degree climbing to 3000'. Leveled at 3000'. Was cleared to 6000'. As we began our climb, noted another air carrier Y turning westbound at our altitude approximately less than 2 mi off our 2 O'clock position. At about 4000' we questioned the controller (128.45) about our traffic. The controller never called out that traffic to us, and it appeared too close for comfort. Callback conversation with reporter revealed the following information. Reporter was asked what the controller's response was when questioned about the traffic. The controller said the traffic is turning away. This analyst explained the controller probably had standard radar sep and did not consider air carrier Y as traffic. Reporter said he filed the report because he was surprised by the traffic and maybe had an altitude deviation.

Original NASA ASRS Text

Title: POSSIBLE LESS THAN STANDARD SEPARATION BETWEEN ACR X AND ACR Y. POSSIBLE SYSTEM ERROR.

Narrative: ACR X DEPARTED RWY 4R AT MDW HDG 090 DEG CLBING TO 3000'. LEVELED AT 3000'. WAS CLRED TO 6000'. AS WE BEGAN OUR CLB, NOTED ANOTHER ACR Y TURNING WBND AT OUR ALT APPROX LESS THAN 2 MI OFF OUR 2 O'CLOCK POS. AT ABOUT 4000' WE QUESTIONED THE CTLR (128.45) ABOUT OUR TFC. THE CTLR NEVER CALLED OUT THAT TFC TO US, AND IT APPEARED TOO CLOSE FOR COMFORT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO. RPTR WAS ASKED WHAT THE CTLR'S RESPONSE WAS WHEN QUESTIONED ABOUT THE TFC. THE CTLR SAID THE TFC IS TURNING AWAY. THIS ANALYST EXPLAINED THE CTLR PROBABLY HAD STANDARD RADAR SEP AND DID NOT CONSIDER ACR Y AS TFC. RPTR SAID HE FILED THE RPT BECAUSE HE WAS SURPRISED BY THE TFC AND MAYBE HAD AN ALT DEV.

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.

Possible less than standard separation between air carrier X and air carrier Y. Possible system error.