Narrative:

We were assigned a 40 degree heading and climb to 17000 ft. ATC asked us to turn left to 40 degree heading. I explained we were already on a 40 degree heading. ATC then told us to fly direct intersection south. At that moment, we entered towering cumulus and encountered moderate to heavy turbulence. I was unable to see or enter direct into the navigation computer direct to intersection south, because of the turbulence. Then we received a TA followed by an RA. Our full attention was now focused on this. As we came on top of the clouds, I observed the other aircraft about 2 or 3 mi south, parallel and opposite direction to our course. I then was able to enter direct intersection south. ATC informed us that there was a loss of separation and that we had turned into the other aircraft. I was in disbelief as I never saw the captain come right of course. If we did go right of course, it was caused by the turbulence. Also, this whole scenario took place in about 1 30 second timeframe. I am displeased that the ATC controller did not give us a heading and altitude hold considering he had to see this conflict unfolding before him. Asking an aircraft to proceed direct to a fix requires some time to set up the navigation computer. A heading would have been much faster and easier to accomplish in heavy turbulence.

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Original NASA ASRS Text

Title: ACR FLT CREW ENCOUNTERS TURB WHILE CLBING TO ALT AND DEVS FROM ASSIGNED COURSE, CAUSING LOSS OF SEPARATION AND A TCASII RA.

Narrative: WE WERE ASSIGNED A 40 DEG HDG AND CLB TO 17000 FT. ATC ASKED US TO TURN L TO 40 DEG HDG. I EXPLAINED WE WERE ALREADY ON A 40 DEG HDG. ATC THEN TOLD US TO FLY DIRECT INTXN S. AT THAT MOMENT, WE ENTERED TOWERING CUMULUS AND ENCOUNTERED MODERATE TO HEAVY TURB. I WAS UNABLE TO SEE OR ENTER DIRECT INTO THE NAV COMPUTER DIRECT TO INTXN S, BECAUSE OF THE TURB. THEN WE RECEIVED A TA FOLLOWED BY AN RA. OUR FULL ATTN WAS NOW FOCUSED ON THIS. AS WE CAME ON TOP OF THE CLOUDS, I OBSERVED THE OTHER ACFT ABOUT 2 OR 3 MI S, PARALLEL AND OPPOSITE DIRECTION TO OUR COURSE. I THEN WAS ABLE TO ENTER DIRECT INTXN S. ATC INFORMED US THAT THERE WAS A LOSS OF SEPARATION AND THAT WE HAD TURNED INTO THE OTHER ACFT. I WAS IN DISBELIEF AS I NEVER SAW THE CAPT COME R OF COURSE. IF WE DID GO R OF COURSE, IT WAS CAUSED BY THE TURB. ALSO, THIS WHOLE SCENARIO TOOK PLACE IN ABOUT 1 30 SECOND TIMEFRAME. I AM DISPLEASED THAT THE ATC CTLR DID NOT GIVE US A HDG AND ALT HOLD CONSIDERING HE HAD TO SEE THIS CONFLICT UNFOLDING BEFORE HIM. ASKING AN ACFT TO PROCEED DIRECT TO A FIX REQUIRES SOME TIME TO SET UP THE NAV COMPUTER. A HDG WOULD HAVE BEEN MUCH FASTER AND EASIER TO ACCOMPLISH IN HEAVY TURB.

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.