Narrative:

I was on local (tower) position. I had been on position approximately 45 mins at time of occurrence. WX was marginal visibility -X 4H but depending on type aircraft and landing light array, often I could not observe aircraft until 2-3 mi from airport. Briefly, numerous aircraft on frequency inbound, pattern outbnd, etc. Small transport a on ILS cross marker cleared to land. Light transport B inbound on ILS. Radio contact with light transport north not established until marker. First direction crq FD or nkx approach passed wrong call sign on light transport B strip. Small aircraft C inbound and told to follow light transport B from modified straight-in 4 northeast starts a right 360 degree towards small aircraft D on right downwind. Small aircraft C has trouble seeing airport burt had reported light transport B in sight and told to follow. Small aircraft east calls east of airport and not admitted into air traffic area. Light transport B again reduced to F as and sequenced #2 behind small transport a. San approach calls and questions a supervisor on sep between small transport a 2-1 1/2 mi and F light transport B approximately 4 mi final. Supervisor accepts visibility and keeps light transport B. Small transport a instructed on 1 mi final to plan to exit highspd, first intersection and cross parallel if necessary. Ground control informed and coordinated with and agrees to protect parallel intersection. Also, when small aircraft a about 1-1 1/2. Small aircraft F requested takeoff but held, I was thinking light transport B might go around and wanted to protect departure corridor. Small aircraft C directed back to final. Observe another target paralleling small aircraft C. Second supervisor in effort to assist plugs into cc position to my right but is blocking BRITE scope. Small transport a crosses threshold and appears will make first at 1700'. Light transport B 1 1/2 mi final approximately and cleared to land. I asked small aircraft east's position. Small aircraft C answers a reporting point on right downwind. Second supervisor points to small aircraft C and says there's the small aircraft east. I know better. I see small transport a miss first and I instruct him to expedite to second in about 3000' from approach end. I scan final and observe small aircraft east inside air traffic area about 2 mi final in proximity to small aircraft C. I scan back to second intersection with light transport B about 1/2 mi out and see to approximately 500' past second intersection or 3700' of 4700'rwy. Note: first supervisor behind to my left scanning final but blocking my view of remainder of runway. (That's why I often situation and even kneel to keep out of local scan when I'm working FD and even ground control sometimes). I start back to instruct small aircraft east away from small aircraft C. When first supervisor (evidently alerted by me last scan) yells out small transport a still on runway (about 4000'). I instantly send light transport B on very short final around. Light transport B crosses threshold supposedly glances tires on runway about 900' from threshold and goes around. Small transport a almost off at end, about 4500' from approach end. Small transport a shortly thereafter reported problem with nose gear. I was relieved west/O adequately briefing second supervisor (relieving controller). I told about all aircraft in air and ground anyway. Distrs 3 aircraft who didn't or couldn't do as instructed. 2 supervisors who didn't have complete picture and were crowding my movement unintentionaly in their efforts to assist. If it was a deal, I'll accept my blame and correct it but should I shoulder all the blame? No!

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Original NASA ASRS Text

Title: TWO ACFT ON RWY WITHOUT PROPER SEPARATION.

Narrative: I WAS ON LCL (TWR) POS. I HAD BEEN ON POS APPROX 45 MINS AT TIME OF OCCURRENCE. WX WAS MARGINAL VISIBILITY -X 4H BUT DEPENDING ON TYPE ACFT AND LNDG LIGHT ARRAY, OFTEN I COULD NOT OBSERVE ACFT UNTIL 2-3 MI FROM ARPT. BRIEFLY, NUMEROUS ACFT ON FREQ INBND, PATTERN OUTBND, ETC. SMT A ON ILS CROSS MARKER CLRED TO LAND. LTT B INBND ON ILS. RADIO CONTACT WITH LTT N NOT ESTABLISHED UNTIL MARKER. FIRST DIRECTION CRQ FD OR NKX APCH PASSED WRONG CALL SIGN ON LTT B STRIP. SMA C INBND AND TOLD TO FOLLOW LTT B FROM MODIFIED STRAIGHT-IN 4 NE STARTS A R 360 DEG TOWARDS SMA D ON R DOWNWIND. SMA C HAS TROUBLE SEEING ARPT BURT HAD RPTED LTT B IN SIGHT AND TOLD TO FOLLOW. SMA E CALLS E OF ARPT AND NOT ADMITTED INTO ATA. LTT B AGAIN REDUCED TO F AS AND SEQUENCED #2 BEHIND SMT A. SAN APCH CALLS AND QUESTIONS A SUPVR ON SEP BTWN SMT A 2-1 1/2 MI AND F LTT B APPROX 4 MI FINAL. SUPVR ACCEPTS VIS AND KEEPS LTT B. SMT A INSTRUCTED ON 1 MI FINAL TO PLAN TO EXIT HIGHSPD, FIRST INTXN AND CROSS PARALLEL IF NECESSARY. GC INFORMED AND COORDINATED WITH AND AGREES TO PROTECT PARALLEL INTXN. ALSO, WHEN SMA A ABOUT 1-1 1/2. SMA F REQUESTED TKOF BUT HELD, I WAS THINKING LTT B MIGHT GO AROUND AND WANTED TO PROTECT DEP CORRIDOR. SMA C DIRECTED BACK TO FINAL. OBSERVE ANOTHER TARGET PARALLELING SMA C. SEC SUPVR IN EFFORT TO ASSIST PLUGS INTO CC POS TO MY R BUT IS BLOCKING BRITE SCOPE. SMT A CROSSES THRESHOLD AND APPEARS WILL MAKE FIRST AT 1700'. LTT B 1 1/2 MI FINAL APPROX AND CLRED TO LAND. I ASKED SMA E'S POS. SMA C ANSWERS A RPTING POINT ON R DOWNWIND. SEC SUPVR POINTS TO SMA C AND SAYS THERE'S THE SMA E. I KNOW BETTER. I SEE SMT A MISS FIRST AND I INSTRUCT HIM TO EXPEDITE TO SEC IN ABOUT 3000' FROM APCH END. I SCAN FINAL AND OBSERVE SMA E INSIDE ATA ABOUT 2 MI FINAL IN PROX TO SMA C. I SCAN BACK TO SEC INTXN WITH LTT B ABOUT 1/2 MI OUT AND SEE TO APPROX 500' PAST SEC INTXN OR 3700' OF 4700'RWY. NOTE: FIRST SUPVR BEHIND TO MY L SCANNING FINAL BUT BLOCKING MY VIEW OF REMAINDER OF RWY. (THAT'S WHY I OFTEN SIT AND EVEN KNEEL TO KEEP OUT OF LCL SCAN WHEN I'M WORKING FD AND EVEN GC SOMETIMES). I START BACK TO INSTRUCT SMA E AWAY FROM SMA C. WHEN FIRST SUPVR (EVIDENTLY ALERTED BY ME LAST SCAN) YELLS OUT SMT A STILL ON RWY (ABOUT 4000'). I INSTANTLY SEND LTT B ON VERY SHORT FINAL AROUND. LTT B CROSSES THRESHOLD SUPPOSEDLY GLANCES TIRES ON RWY ABOUT 900' FROM THRESHOLD AND GOES AROUND. SMT A ALMOST OFF AT END, ABOUT 4500' FROM APCH END. SMT A SHORTLY THEREAFTER RPTED PROB WITH NOSE GEAR. I WAS RELIEVED W/O ADEQUATELY BRIEFING SEC SUPVR (RELIEVING CTLR). I TOLD ABOUT ALL ACFT IN AIR AND GND ANYWAY. DISTRS 3 ACFT WHO DIDN'T OR COULDN'T DO AS INSTRUCTED. 2 SUPVRS WHO DIDN'T HAVE COMPLETE PICTURE AND WERE CROWDING MY MOVEMENT UNINTENTIONALY IN THEIR EFFORTS TO ASSIST. IF IT WAS A DEAL, I'LL ACCEPT MY BLAME AND CORRECT IT BUT SHOULD I SHOULDER ALL THE BLAME? NO!

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.