Lax controller described an identified separation error when an aircraft instructed to maintain visu...

Narrative:

A B738 was cleared for takeoff runway 25L. A CL30 was put in position and asked to report preceding traffic in sight and he did. He was then cleared for takeoff and on the upwind he was told to maintain visual separation and contact departure. He responded with 'maintain visual separation and contact departure good day' no call sign. I feel this is a trap because the local controller I said everything correct and since the pilot doesn't respond with his call sign and leaves the frequency it was called an operator error. Recommendation; you could get the visual separation prior to the aircraft leaving the frequency. Pilots should be criticized for not using their call signs during critical read backs.

Original NASA ASRS Text

Title: LAX Controller described an identified separation error when an aircraft instructed to maintain visual separation failed to acknowledge with a callsign.

Narrative: A B738 was cleared for takeoff Runway 25L. A CL30 was put in position and asked to report preceding traffic in sight and he did. He was then cleared for takeoff and on the upwind he was told to maintain visual separation and contact departure. He responded with 'maintain visual separation and contact Departure good day' no call sign. I feel this is a trap because the Local Controller I said everything correct and since the pilot doesn't respond with his call sign and leaves the frequency it was called an Operator Error. Recommendation; you could get the visual separation prior to the aircraft leaving the frequency. Pilots should be criticized for not using their call signs during critical read backs.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	943175
Time
Date	201104
Local Time Of Day	1201-1800
Place
Locale Reference	LAX.Tower
State Reference	CA
Aircraft 1
Make Model Name	Challenger 300
Flight Phase	Initial Climb
Flight Plan	IFR
Aircraft 2
Make Model Name	B737-800
Flight Phase	Initial Climb
Person 1
Function	Handoff / Assist Local
Qualification	Air Traffic Control Fully Certified
Events
Anomaly	ATC Issue All Types Deviation - Procedural Published Material / Policy

Lax controller described an identified separation error when an aircraft instructed to maintain visual separation failed to acknowledge with a callsign.