Narrative:

After departure we were cleared to maintain 6000 ft via the river 5 departure. The tower assigned runway heading rather than the 085 degree radial as the departure calls for. After contacting departure, a heading of 140 degrees was assigned and was being flown to an altitude of 6000 ft. As we approach 6000 ft departure informed us of traffic 12 O'clock. I called out our altitude to the first officer, the PF, and I started to look outside for the traffic. As I spotted the traffic aircraft, I realized as did the first officer and ATC that we had drifted off our altitude. We made immediate, positive corrections, which included power reductions and lowering of the nose of the aircraft. This was followed by ATC notifying us of the altitude deviation. ATC assigned a heading of 090 degrees which was executed. Traffic passed well clear of us by 1-2 mi horizontally. Both aircraft had visual contact with each other. Shortly thereafter, ATC returned us to a heading of 140 degrees with a climb to 10000 ft. ATC made no other comments concerning the situation. Some of the contributing factors were WX related. With the overcast skies, lack of visual horizon, and looking for a white aircraft against an opaque backgnd, the normal visual cues to being level or climbing were not readily apparent. All actions by the crew to correct this deviation were done with immediate action by the crew. Supplemental information from acn 289174: after contacting departure control, we were instructed to turn right 140 degrees and climb and maintain 6000 ft. I then executed turn to 140 degrees and climb to 6000 ft. Just prior to reaching the assigned altitude, were instructed by departure control to look for traffic, a citation jet, at 12 O'clock at 7000 ft. After positive contact with traffic, I realized that I was off of the assigned altitude and took appropriate, immediate action and expedited a descent back to the assigned altitude.

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Original NASA ASRS Text

Title: ALTDEV DURING DEP FROM ARPT.

Narrative: AFTER DEP WE WERE CLRED TO MAINTAIN 6000 FT VIA THE RIVER 5 DEP. THE TWR ASSIGNED RWY HDG RATHER THAN THE 085 DEG RADIAL AS THE DEP CALLS FOR. AFTER CONTACTING DEP, A HDG OF 140 DEGS WAS ASSIGNED AND WAS BEING FLOWN TO AN ALT OF 6000 FT. AS WE APCH 6000 FT DEP INFORMED US OF TFC 12 O'CLOCK. I CALLED OUT OUR ALT TO THE FO, THE PF, AND I STARTED TO LOOK OUTSIDE FOR THE TFC. AS I SPOTTED THE TFC ACFT, I REALIZED AS DID THE FO AND ATC THAT WE HAD DRIFTED OFF OUR ALT. WE MADE IMMEDIATE, POSITIVE CORRECTIONS, WHICH INCLUDED PWR REDUCTIONS AND LOWERING OF THE NOSE OF THE ACFT. THIS WAS FOLLOWED BY ATC NOTIFYING US OF THE ALTDEV. ATC ASSIGNED A HDG OF 090 DEGS WHICH WAS EXECUTED. TFC PASSED WELL CLR OF US BY 1-2 MI HORIZLY. BOTH ACFT HAD VISUAL CONTACT WITH EACH OTHER. SHORTLY THEREAFTER, ATC RETURNED US TO A HDG OF 140 DEGS WITH A CLB TO 10000 FT. ATC MADE NO OTHER COMMENTS CONCERNING THE SIT. SOME OF THE CONTRIBUTING FACTORS WERE WX RELATED. WITH THE OVCST SKIES, LACK OF VISUAL HORIZON, AND LOOKING FOR A WHITE ACFT AGAINST AN OPAQUE BACKGND, THE NORMAL VISUAL CUES TO BEING LEVEL OR CLBING WERE NOT READILY APPARENT. ALL ACTIONS BY THE CREW TO CORRECT THIS DEV WERE DONE WITH IMMEDIATE ACTION BY THE CREW. SUPPLEMENTAL INFO FROM ACN 289174: AFTER CONTACTING DEP CTL, WE WERE INSTRUCTED TO TURN R 140 DEGS AND CLB AND MAINTAIN 6000 FT. I THEN EXECUTED TURN TO 140 DEGS AND CLB TO 6000 FT. JUST PRIOR TO REACHING THE ASSIGNED ALT, WERE INSTRUCTED BY DEP CTL TO LOOK FOR TFC, A CITATION JET, AT 12 O'CLOCK AT 7000 FT. AFTER POSITIVE CONTACT WITH TFC, I REALIZED THAT I WAS OFF OF THE ASSIGNED ALT AND TOOK APPROPRIATE, IMMEDIATE ACTION AND EXPEDITED A DSCNT BACK TO THE ASSIGNED ALT.

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.