Air carrier X had less than standard separation from air carrier Y. System error.

Attributes
ACN	188801
Time
Date	199109
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : dfw
State Reference	TX
Altitude	msl bound lower : 3000 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : dfw tower : gso
Operator	common carrier : air carrier
Make Model Name	Light Transport
Navigation In Use	Other Other
Flight Phase	cruise other cruise other
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
Flight Phase	cruise other
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 240 flight time total : 8000 flight time type : 3400
ASRS Report	188801
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : required legal separation
Independent Detector	other flight crewa other other : unspecified
Resolutory Action	none taken : detected after the fact
Consequence	Other
Miss Distance	horizontal : 6000 vertical : 0
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

After departure, air carrier X received a clearance to climb to 4000 ft, heading 060 degree. Shortly thereafter, received amended clearance to amend altitude to 3000 ft, heading 070 degree. Received frequency change, also heading change to 360 degree, still no climb clearance. Approximately 45 mins later, I looked to my 10 O'clock position and I noticed air carrier X at our altitude about 1 mi away converging. He passed off our left wing. A full 5 seconds later we received a clearance to turn right immediately 090 degree. Shortly thereafter, we turned back on course and climbed to 4000 ft. Also a different voice was on departure. We proceeded without further incident.

Original NASA ASRS Text

Title: ACR X HAD LTSS FROM ACR Y. SYS ERROR.

Narrative: AFTER DEP, ACR X RECEIVED A CLRNC TO CLB TO 4000 FT, HDG 060 DEG. SHORTLY THEREAFTER, RECEIVED AMENDED CLRNC TO AMEND ALT TO 3000 FT, HDG 070 DEG. RECEIVED FREQ CHANGE, ALSO HDG CHANGE TO 360 DEG, STILL NO CLB CLRNC. APPROX 45 MINS LATER, I LOOKED TO MY 10 O'CLOCK POS AND I NOTICED ACR X AT OUR ALT ABOUT 1 MI AWAY CONVERGING. HE PASSED OFF OUR L WING. A FULL 5 SECONDS LATER WE RECEIVED A CLRNC TO TURN R IMMEDIATELY 090 DEG. SHORTLY THEREAFTER, WE TURNED BACK ON COURSE AND CLBED TO 4000 FT. ALSO A DIFFERENT VOICE WAS ON DEP. WE PROCEEDED WITHOUT FURTHER INCIDENT.

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.