Narrative:

Tower was initially working both aircraft. Departure sector had holds on level III VFR tower. A release on both aircraft was requested from the departure sector and received. Local control departed #1 aircraft and placed #2 aircraft in position. Both aircraft were CAT III, considered same speed. Tower and approach control letter of agreement required tower to provide initial sep of 3 mi in trail. When #1 aircraft was 1 1/2 mi out, anticipated sep existed and #2 aircraft was cleared for takeoff. Control of #1 aircraft was given to departure approximately 1/2 mi south of the airport as was #2 aircraft. When #2 aircraft was approximately 1-1 1/2 mi south the cabin coordinator observed that the airspeed of the #2 aircraft was approximately 60 KTS faster than #1 aircraft and attempted to advise departure sector of the difference of airspeed. No response was received from departure sector. #2 aircraft overtook #1 aircraft approximately 5 mi south of the airport with no apparent attempt to divert courses. Radar vacuum advised tower did not provide required initial sep. Approximately 10-20 mins after the incident, departure sectors pacific and oneil were de-combined, and at the time of the incident this combined sector was possibly working west/O a handoff man. Additional contributing factors: #1 aircraft flew a noise abatement profile which he was not expected nor required to fly. Departure sector was spinning traffic en route to and over san airspace. I think a number of factors contributed to this incident. 1) climb out speed of #1 aircraft--his speed was 60-80 KTS slower than normal. 2) airspace saturation at san. 3) positions combined up during period of IFR WX. 4) possible understaffing of departure positions--no handoff. I feel that had the #1 aircraft better known his requirements, this situation would not have occurred, or had the departure sector been properly manned and separated, a course deviation could have been issued.

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Original NASA ASRS Text

Title: LTT RELEASED BEHIND A SLOWER SMT RESULTING IN LESS THAN STANDARD SEPARATION SOUTH OF ARPT.

Narrative: TWR WAS INITIALLY WORKING BOTH ACFT. DEP SECTOR HAD HOLDS ON LEVEL III VFR TWR. A RELEASE ON BOTH ACFT WAS REQUESTED FROM THE DEP SECTOR AND RECEIVED. LCL CTL DEPARTED #1 ACFT AND PLACED #2 ACFT IN POS. BOTH ACFT WERE CAT III, CONSIDERED SAME SPD. TWR AND APCH CTL LETTER OF AGREEMENT REQUIRED TWR TO PROVIDE INITIAL SEP OF 3 MI IN TRAIL. WHEN #1 ACFT WAS 1 1/2 MI OUT, ANTICIPATED SEP EXISTED AND #2 ACFT WAS CLRED FOR TKOF. CTL OF #1 ACFT WAS GIVEN TO DEP APPROX 1/2 MI S OF THE ARPT AS WAS #2 ACFT. WHEN #2 ACFT WAS APPROX 1-1 1/2 MI S THE CABIN COORDINATOR OBSERVED THAT THE AIRSPD OF THE #2 ACFT WAS APPROX 60 KTS FASTER THAN #1 ACFT AND ATTEMPTED TO ADVISE DEP SECTOR OF THE DIFFERENCE OF AIRSPD. NO RESPONSE WAS RECEIVED FROM DEP SECTOR. #2 ACFT OVERTOOK #1 ACFT APPROX 5 MI S OF THE ARPT WITH NO APPARENT ATTEMPT TO DIVERT COURSES. RADAR VACUUM ADVISED TWR DID NOT PROVIDE REQUIRED INITIAL SEP. APPROX 10-20 MINS AFTER THE INCIDENT, DEP SECTORS PACIFIC AND ONEIL WERE DE-COMBINED, AND AT THE TIME OF THE INCIDENT THIS COMBINED SECTOR WAS POSSIBLY WORKING W/O A HDOF MAN. ADDITIONAL CONTRIBUTING FACTORS: #1 ACFT FLEW A NOISE ABATEMENT PROFILE WHICH HE WAS NOT EXPECTED NOR REQUIRED TO FLY. DEP SECTOR WAS SPINNING TFC ENRTE TO AND OVER SAN AIRSPACE. I THINK A NUMBER OF FACTORS CONTRIBUTED TO THIS INCIDENT. 1) CLBOUT SPD OF #1 ACFT--HIS SPD WAS 60-80 KTS SLOWER THAN NORMAL. 2) AIRSPACE SATURATION AT SAN. 3) POSITIONS COMBINED UP DURING PERIOD OF IFR WX. 4) POSSIBLE UNDERSTAFFING OF DEP POSITIONS--NO HDOF. I FEEL THAT HAD THE #1 ACFT BETTER KNOWN HIS REQUIREMENTS, THIS SITUATION WOULD NOT HAVE OCCURRED, OR HAD THE DEP SECTOR BEEN PROPERLY MANNED AND SEPARATED, A COURSE DEVIATION COULD HAVE BEEN ISSUED.

Data retrieved from NASA's ASRS site as of August 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.