Narrative:

Bos 2 departure runway 4L has a right turn to 090 degrees at 4 DME. We were held down to 3000 ft on departure and as we leveled at 3000 ft, we got a TCASII RA for VFR traffic at 3500 ft. The traffic was directly above our 090 degree heading track. WX was scattered clouds and haze. At 1 mi (with TA alerts) spacing we could not see the VFR traffic. I told ATC I was going to continue on runway heading (040 degrees) until clear of traffic before turning to 090 degrees. Bos departure advised 'he's in a VFR hold and knows what he's doing, go ahead and turn.' I did not believe it safe to turn and continued to about 5.5 DME and then turned to 090 degrees. ATC advised I had flown into a noise sensitive area. I advised bos departure I did not believe it safe to turn at 4 DME. No further conflicts or pertinent radio traffic. Why is a VFR aircraft in high density class B airspace in very marginal VFR WX? Holding directly above our departure route by 500 ft, we will always get an RA to descend in this scenario. The traffic apparently is there, routinely.

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Original NASA ASRS Text

Title: A DEP B737-800 PIC IS CHIDED FOR FLYING INTO A NOISE SENSITIVE AREA WHEN HE HAD DELAYED HIS LOGAN 2 DEP PROC TURN AT 4 DME TO 100 DEGS FOR 1 PT 5 NM. CAPT MADE THE DECISION BECAUSE OF VFR TFC HOLDING ON HIS PROJECTED DEP RTE 500 FT ABOVE, 4 NM FROM BOS, MA.

Narrative: BOS 2 DEP RWY 4L HAS A R TURN TO 090 DEGS AT 4 DME. WE WERE HELD DOWN TO 3000 FT ON DEP AND AS WE LEVELED AT 3000 FT, WE GOT A TCASII RA FOR VFR TFC AT 3500 FT. THE TFC WAS DIRECTLY ABOVE OUR 090 DEG HDG TRACK. WX WAS SCATTERED CLOUDS AND HAZE. AT 1 MI (WITH TA ALERTS) SPACING WE COULD NOT SEE THE VFR TFC. I TOLD ATC I WAS GOING TO CONTINUE ON RWY HDG (040 DEGS) UNTIL CLR OF TFC BEFORE TURNING TO 090 DEGS. BOS DEP ADVISED 'HE'S IN A VFR HOLD AND KNOWS WHAT HE'S DOING, GO AHEAD AND TURN.' I DID NOT BELIEVE IT SAFE TO TURN AND CONTINUED TO ABOUT 5.5 DME AND THEN TURNED TO 090 DEGS. ATC ADVISED I HAD FLOWN INTO A NOISE SENSITIVE AREA. I ADVISED BOS DEP I DID NOT BELIEVE IT SAFE TO TURN AT 4 DME. NO FURTHER CONFLICTS OR PERTINENT RADIO TFC. WHY IS A VFR ACFT IN HIGH DENSITY CLASS B AIRSPACE IN VERY MARGINAL VFR WX? HOLDING DIRECTLY ABOVE OUR DEP RTE BY 500 FT, WE WILL ALWAYS GET AN RA TO DSND IN THIS SCENARIO. THE TFC APPARENTLY IS THERE, ROUTINELY.

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.