Controller intervened to maintain standard separation between aircraft X and aircraft Y. Visual sepa...

Attributes
ACN	202985
Time
Date	199202
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : stl
State Reference	MO
Altitude	msl bound lower : 4000 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : stl tower : las
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	climbout : intermediate altitude
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	climbout : intermediate altitude
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : departure
Qualification	controller : radar
ASRS Report	202985
Person 2
Affiliation	government : faa
Function	controller : local
Qualification	controller : non radar
ASRS Report	202985
Events
Anomaly	conflict : airborne less severe
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	Other
Miss Distance	horizontal : 24000 vertical : 0
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other

Narrative:

Aircraft X departed stl on a 360 degree heading. When he was approximately 4 mi north aircraft Y departed on a 330 degree heading, and aircraft Y subsequently did not tag up until 4 mi northwest. The separation had decreased to less than 5 mi by the time he tagged up. I stopped aircraft X at 40 when the jet finally tagged up, stl tower had coordinated with another controller using a 330 degree heading for jets and 360 degree for propellers but, would have 1 of the aircraft use visual separation. In this case, the propeller was too far out to use visual, but the jet caught him very rapidly. Our standard procedure is to use 45 degree separation, but someone had different ideas. I was working low altitude north and on numerous occasions lost radar contact with traffic. I think someone put too much emphasis on departing aircraft, than on safety. The non-radar headings should be used.

Original NASA ASRS Text

Title: CTLR INTERVENED TO MAINTAIN STANDARD SEPARATION BTWN ACFT X AND ACFT Y. VISUAL SEPARATION IN USE.

Narrative: ACFT X DEPARTED STL ON A 360 DEG HDG. WHEN HE WAS APPROX 4 MI N ACFT Y DEPARTED ON A 330 DEG HDG, AND ACFT Y SUBSEQUENTLY DID NOT TAG UP UNTIL 4 MI NW. THE SEPARATION HAD DECREASED TO LESS THAN 5 MI BY THE TIME HE TAGGED UP. I STOPPED ACFT X AT 40 WHEN THE JET FINALLY TAGGED UP, STL TWR HAD COORDINATED WITH ANOTHER CTLR USING A 330 DEG HDG FOR JETS AND 360 DEG FOR PROPS BUT, WOULD HAVE 1 OF THE ACFT USE VISUAL SEPARATION. IN THIS CASE, THE PROP WAS TOO FAR OUT TO USE VISUAL, BUT THE JET CAUGHT HIM VERY RAPIDLY. OUR STANDARD PROC IS TO USE 45 DEG SEPARATION, BUT SOMEONE HAD DIFFERENT IDEAS. I WAS WORKING LOW ALT N AND ON NUMEROUS OCCASIONS LOST RADAR CONTACT WITH TFC. I THINK SOMEONE PUT TOO MUCH EMPHASIS ON DEPARTING ACFT, THAN ON SAFETY. THE NON-RADAR HDGS SHOULD BE USED.

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.

Controller intervened to maintain standard separation between aircraft X and aircraft Y. Visual separation in use.