Tower local controller released 2 aircraft on parallel runways with the lead aircraft turning in front of the trailing aircraft. The second aircraft received a TCASII RA and the departure controller intervened, however, less than standard separation had occurred.

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Attributes
ACN	339707
Time
Date	199606
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : lax
State Reference	CA
Altitude	agl bound lower : 0 agl bound upper : 2500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : lax tower : lax
Operator	common carrier : air carrier
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	climbout : initial
Route In Use	departure sid : sid
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Small Transport, Low Wing, 2 Turboprop Eng
Flight Phase	climbout : initial
Route In Use	departure other enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : departure
Qualification	controller : radar
Experience	controller military : 5 controller radar : 7
ASRS Report	339707
Person 2
Affiliation	government : faa
Function	controller : local
Qualification	controller : radar
Events
Anomaly	conflict : nmac non adherence : published procedure non adherence : required legal separation other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other controllera other flight crewa
Resolutory Action	controller : issued new clearance other
Consequence	Other
Miss Distance	horizontal : 0 vertical : 500
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

The metroliner departed first and was given a climb to 9000 ft and a turn to a heading of 190 degrees. The tower advised that air carrier X had the metroliner in sight and he departed climbing to 3000 ft, I then issued 13000 ft and the normal speed assignment (250 KTS). The metroliner was turning slowly and I noticed air carrier X would be inside of his sbound turn. I immediately stopped air carrier X at 2000 ft but he was already through that altitude. He then stopped at 2500 ft and advised he was getting an TCASII RA. The metroliner advised he had air carrier X in sight and the B737 was passing above him and he was maintaining visual. The courses diverged and things proceeded normally. Cause of the situation can be attributed to aircraft performance, the lead aircraft climbing and turning slower than the trailer. Secondly, the tower is not ensuring that the smaller aircraft are turning as they have in the past with the change in the clrncs in the tower en route system. The new clrncs leave it up to the pilot to turn when the clearance dictates. Lastly, performance has to be considered prior to departing aircraft closely or visually.

Original NASA ASRS Text

Title: TWR LCL CTLR RELEASED 2 ACFT ON PARALLEL RWYS WITH THE LEAD ACFT TURNING IN FRONT OF THE TRAILING ACFT. THE SECOND ACFT RECEIVED A TCASII RA AND THE DEP CTLR INTERVENED, HOWEVER, LTSS HAD OCCURRED.

Narrative: THE METROLINER DEPARTED FIRST AND WAS GIVEN A CLB TO 9000 FT AND A TURN TO A HDG OF 190 DEGS. THE TWR ADVISED THAT ACR X HAD THE METROLINER IN SIGHT AND HE DEPARTED CLBING TO 3000 FT, I THEN ISSUED 13000 FT AND THE NORMAL SPD ASSIGNMENT (250 KTS). THE METROLINER WAS TURNING SLOWLY AND I NOTICED ACR X WOULD BE INSIDE OF HIS SBOUND TURN. I IMMEDIATELY STOPPED ACR X AT 2000 FT BUT HE WAS ALREADY THROUGH THAT ALT. HE THEN STOPPED AT 2500 FT AND ADVISED HE WAS GETTING AN TCASII RA. THE METROLINER ADVISED HE HAD ACR X IN SIGHT AND THE B737 WAS PASSING ABOVE HIM AND HE WAS MAINTAINING VISUAL. THE COURSES DIVERGED AND THINGS PROCEEDED NORMALLY. CAUSE OF THE SIT CAN BE ATTRIBUTED TO ACFT PERFORMANCE, THE LEAD ACFT CLBING AND TURNING SLOWER THAN THE TRAILER. SECONDLY, THE TWR IS NOT ENSURING THAT THE SMALLER ACFT ARE TURNING AS THEY HAVE IN THE PAST WITH THE CHANGE IN THE CLRNCS IN THE TWR ENRTE SYS. THE NEW CLRNCS LEAVE IT UP TO THE PLT TO TURN WHEN THE CLRNC DICTATES. LASTLY, PERFORMANCE HAS TO BE CONSIDERED PRIOR TO DEPARTING ACFT CLOSELY OR VISUALLY.

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.