Narrative:

Aircraft #2 was on 3 mi final ILS runway 28R (5 DME localizer). Aircraft #1 was 5 mi in trail cleared ILS runway 28R approach. Aircraft #2 speed indicated 30 KTS faster than aircraft #1. On initial contact, I asked aircraft #1 if they had aircraft #2 in sight. Reply was negative, they were IMC. By now separation had decreased to just over 4 mi, aircraft #1 was still faster. I issued aircraft #1 a missed approach. I subsequently had 2 more aircraft on final shipped to me by approach, faster than aircraft ahead, with insufficient spacing to allow a legal approach. After a short break I was working radar coordinator position and approach gave tower 3 arrs within 15 mins, too close and too fast to allow legal approach. There were also several approachs which were just legal.

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Original NASA ASRS Text

Title: ATCT LCL CTLR INITIATES GAR FOR ACFT ON FINAL APCH THAT HE PERCEIVES ARE AT INSUFFICIENT SPACING FOR TYPE WT CATEGORY.

Narrative: ACFT #2 WAS ON 3 MI FINAL ILS RWY 28R (5 DME LOC). ACFT #1 WAS 5 MI IN TRAIL CLRED ILS RWY 28R APCH. ACFT #2 SPD INDICATED 30 KTS FASTER THAN ACFT #1. ON INITIAL CONTACT, I ASKED ACFT #1 IF THEY HAD ACFT #2 IN SIGHT. REPLY WAS NEGATIVE, THEY WERE IMC. BY NOW SEPARATION HAD DECREASED TO JUST OVER 4 MI, ACFT #1 WAS STILL FASTER. I ISSUED ACFT #1 A MISSED APCH. I SUBSEQUENTLY HAD 2 MORE ACFT ON FINAL SHIPPED TO ME BY APCH, FASTER THAN ACFT AHEAD, WITH INSUFFICIENT SPACING TO ALLOW A LEGAL APCH. AFTER A SHORT BREAK I WAS WORKING RADAR COORDINATOR POS AND APCH GAVE TWR 3 ARRS WITHIN 15 MINS, TOO CLOSE AND TOO FAST TO ALLOW LEGAL APCH. THERE WERE ALSO SEVERAL APCHS WHICH WERE JUST LEGAL.

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.