Narrative:

We were flying a right downwind for runway 26 at iah. Approach asked if we had the air carrier in sight on a right base leg for runway 26. We called it in sight, and approach cleared us for a visual approach behind the air carrier. We turned right, heading 180 degrees for our base leg, descending, and doing the checklists, and I was having just a little difficulty keeping the air carrier in sight through the haze. But the problem arose when the localizer needle uncaged for the localizer to runway 26. I couldn't see the runway, but I could see now on the CDI display that I was going to go through the 26 centerline, so I cranked it over into a right turn. By the time I was heading west, I could see the runways, and I had crossed south of the runway 27 centerline as well. Approach told us to stop our descent for several mi, I assume for conflicting traffic coming in below us for runway 27, and I got reestablished on the runway 26 centerline. The cause of the confusion and possible loss of separation was poor visibility and our inability to see the runway. If there is any possibility of an overshoot to the runway, approach should stagger the aircraft so that a conflict does not occur. Or, approach could give a vector to intercept the final approach course, or ask if we had the airport in sight.

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Original NASA ASRS Text

Title: AN ACR MLG OVERSHOT THE LOC WHILE LOOKING FOR OTHER TFC IN THE HAZE.

Narrative: WE WERE FLYING A R DOWNWIND FOR RWY 26 AT IAH. APCH ASKED IF WE HAD THE ACR IN SIGHT ON A R BASE LEG FOR RWY 26. WE CALLED IT IN SIGHT, AND APCH CLRED US FOR A VISUAL APCH BEHIND THE ACR. WE TURNED R, HDG 180 DEGS FOR OUR BASE LEG, DSNDING, AND DOING THE CHKLISTS, AND I WAS HAVING JUST A LITTLE DIFFICULTY KEEPING THE ACR IN SIGHT THROUGH THE HAZE. BUT THE PROB AROSE WHEN THE LOC NEEDLE UNCAGED FOR THE LOC TO RWY 26. I COULDN'T SEE THE RWY, BUT I COULD SEE NOW ON THE CDI DISPLAY THAT I WAS GOING TO GO THROUGH THE 26 CTRLINE, SO I CRANKED IT OVER INTO A R TURN. BY THE TIME I WAS HDG W, I COULD SEE THE RWYS, AND I HAD CROSSED S OF THE RWY 27 CTRLINE AS WELL. APCH TOLD US TO STOP OUR DSCNT FOR SEVERAL MI, I ASSUME FOR CONFLICTING TFC COMING IN BELOW US FOR RWY 27, AND I GOT REESTABLISHED ON THE RWY 26 CTRLINE. THE CAUSE OF THE CONFUSION AND POSSIBLE LOSS OF SEPARATION WAS POOR VISIBILITY AND OUR INABILITY TO SEE THE RWY. IF THERE IS ANY POSSIBILITY OF AN OVERSHOOT TO THE RWY, APCH SHOULD STAGGER THE ACFT SO THAT A CONFLICT DOES NOT OCCUR. OR, APCH COULD GIVE A VECTOR TO INTERCEPT THE FINAL APCH COURSE, OR ASK IF WE HAD THE ARPT IN SIGHT.

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.