Light transport complies with TCASII RA contrary to ATC instructions.

Attributes
ACN	234064
Time
Date	199302
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : bos
State Reference	MA
Altitude	msl bound lower : 4000 msl bound upper : 4300
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : bos
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Flight Phase	cruise other
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise other
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 210 flight time total : 3700
ASRS Report	234064
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	conflict : airborne less severe non adherence : clearance non adherence : far non adherence : required legal separation
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 6000 vertical : 800
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation other

Narrative:

Departing from boston, switched to departure frequency. Told to climb, maintain 4000 ft. Entered clouds at 3700 ft and subsequently maintained 4000 ft. We were given VFR traffic at 11 O'clock, 5 mi. Responded traffic not in sight we are IMC. We got a TA, followed by an RA which we chose to follow. Climbed to about 4300 ft then was questioned by ATC. We told them we had an RA and was flying the maneuver. ATC directed us to descend back down to 4000 ft, that there was also traffic at 5000 ft. I responded with a negative, that I was still complying with the RA and we never saw the 3500 ft traffic and there was no way he had VFR cloud clearance. (We entered IMC at 3700 ft) and he then gave us a turn to the east and told us to notify him at our destination.

Original NASA ASRS Text

Title: LTT COMPLIES WITH TCASII RA CONTRARY TO ATC INSTRUCTIONS.

Narrative: DEPARTING FROM BOSTON, SWITCHED TO DEP FREQ. TOLD TO CLB, MAINTAIN 4000 FT. ENTERED CLOUDS AT 3700 FT AND SUBSEQUENTLY MAINTAINED 4000 FT. WE WERE GIVEN VFR TFC AT 11 O'CLOCK, 5 MI. RESPONDED TFC NOT IN SIGHT WE ARE IMC. WE GOT A TA, FOLLOWED BY AN RA WHICH WE CHOSE TO FOLLOW. CLBED TO ABOUT 4300 FT THEN WAS QUESTIONED BY ATC. WE TOLD THEM WE HAD AN RA AND WAS FLYING THE MANEUVER. ATC DIRECTED US TO DSND BACK DOWN TO 4000 FT, THAT THERE WAS ALSO TFC AT 5000 FT. I RESPONDED WITH A NEGATIVE, THAT I WAS STILL COMPLYING WITH THE RA AND WE NEVER SAW THE 3500 FT TFC AND THERE WAS NO WAY HE HAD VFR CLOUD CLRNC. (WE ENTERED IMC AT 3700 FT) AND HE THEN GAVE US A TURN TO THE E AND TOLD US TO NOTIFY HIM AT OUR DEST.

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.