ACR COMPLAINS ABOUT LNDG WITH ANOTHER ACFT DEPARTING.

Narrative

WHILE ON FINAL; INSIDE THE MARKER FOR RWY 33L; WE HEARD TWR CLR ANOTHER ACFT TO TKOF ON OUR RWY. AS WE GOT CLOSER IN; WE SPOTTED A 2 ENG; COMMUTER TYPE ACFT TAKING THE RWY ABOUT 1/3 OF THE WAY DOWN THE RWY AT TAXIWAY GOLD; I THINK. TWR REQUESTED AN EXPEDITED TKOF FROM THE ACFT. HOWEVER; ON THIS OCCASION; THE SEPARATION SEEMED A LITTLE LESS THAN USUAL AND THE ACFT DID NOT APPEAR TO EXPEDITE HIS DEP (HE SEEMED TO HAVE A LONGER THAN NORMAL ROLL AND SLOW ROTATION; POSSIBLY HE WAS HVY). AS WE REACHED APPROX 200 FT; THE ACFT STILL HAD NOT ROTATED; ALTHOUGH IT WAS APPARENT THAT ROTATION WAS IMMINENT. IT ALSO BECAME OBVIOUS THAT IF WE INITIATED A GAR AT THAT POINT; THAT WE WOULD PASS VERY CLOSE TO THE DEPARTING ACFT (DUE TO SPD DIFFERENTIAL). I WAS NOT PLEASED WITH THE SITUATION THAT HAD DEVELOPED BUT FELT THAT CONTINUATION OF THE APCH AND LNDG WAS THE BEST COURSE OF ACTION. THE OTHER ACFT FINALLY GOT OFF OF THE GND AS WE PASSED ABOUT 100 FT. I FEEL THAT ACFT SEPARATION WAS MINIMAL DURING THIS EVENT AND THAT THE TKOF CLRNC SHOULD NOT HAVE BEEN ISSUED. FURTHERMORE THE SITUATION RAPIDLY DEVELOPED TO THE POINT WHERE A GAR WOULD ENTAIL AS MUCH RISK AS LNDG WITH MARGINAL SEPARATION. THESE MINIMAL SEPARATION EVENTS HAVE BECOME A RATHER COMMON OCCURRENCE AT MAJOR ARPTS. WE PLTS HAVE BECOME ACCUSTOMED TO TRUSTING THE TWR'S JUDGEMENT. WHEN THE TWR'S JUDGEMENT IS POOR OR AN ACFT DOESN'T PERFORM AS EXPECTED; THE SITUATION CAN DETERIORATE RAPIDLY WITH ONLY POOR ALTERNATIVES AVAILABLE TO EVERYONE INVOLVED. I CAN ONLY RECOMMEND THAT TWRS OPEN UP THE SEPARATION A LITTLE MORE TO ALLOW FOR DIFFERENCES IN ACFT/PLT PERFORMANCE. I WOULD ALSO SUGGEST THAT AN ALT BE SELECTED (SAY 500 FT) THAT WOULD REQUIRE A GAR IF THE RWY IS NOT CLR. IN OTHER WORDS FORCE A GAR EARLY ON SO THAT SITUATIONS SIMILAR TO THAT WHICH I ENCOUNTERED DO NOT DEVELOP.