Narrative:

Visual approachs to runway 26L and runway 26R were in use. We were coming in from the north. The medium large transport Y was coming in from the southeast. The medium large transport Y was cleared visual approach 26R and we were cleared visual approach 26L. This required a criss-cross for both our aircraft to align ourselves to final approach. I have flown in and out of den hundreds of times in the last 7 yrs. Standard procedures are: aircraft from south on 26L; aircraft from north on 26R. 99 percent of the time this is the way it is done and rightly so. While the captain and so were aware that we were cleared for the left runway, I assumed we were cleared for the right. When I was in a right turn for the final approach course, I could not see the medium large transport Y. The other crew members questioned my intentions and it was then I realized my mistake. I quickly squared my base so as to go behind him. We were about 700-1000 ft above him but only 2400 ft horizontally. I feel this was a little close, but not in any danger. The controller could have easily changed our runways, which would have made a safer situation. I am reporting this so perhaps additional rules might be considered with this particular type of visual approach. It doesn't make good sense to criss-cross aircraft to the final approach course.

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Original NASA ASRS Text

Title: LGT LINED UP FOR WRONG RWY ON VISUAL APCH AND HAS CLOSE PROX WITH MLG.

Narrative: VISUAL APCHS TO RWY 26L AND RWY 26R WERE IN USE. WE WERE COMING IN FROM THE N. THE MLG Y WAS COMING IN FROM THE SE. THE MLG Y WAS CLRED VISUAL APCH 26R AND WE WERE CLRED VISUAL APCH 26L. THIS REQUIRED A CRISS-CROSS FOR BOTH OUR ACFT TO ALIGN OURSELVES TO FINAL APCH. I HAVE FLOWN IN AND OUT OF DEN HUNDREDS OF TIMES IN THE LAST 7 YRS. STANDARD PROCS ARE: ACFT FROM S ON 26L; ACFT FROM N ON 26R. 99 PERCENT OF THE TIME THIS IS THE WAY IT IS DONE AND RIGHTLY SO. WHILE THE CAPT AND SO WERE AWARE THAT WE WERE CLRED FOR THE L RWY, I ASSUMED WE WERE CLRED FOR THE R. WHEN I WAS IN A R TURN FOR THE FINAL APCH COURSE, I COULD NOT SEE THE MLG Y. THE OTHER CREW MEMBERS QUESTIONED MY INTENTIONS AND IT WAS THEN I REALIZED MY MISTAKE. I QUICKLY SQUARED MY BASE SO AS TO GO BEHIND HIM. WE WERE ABOUT 700-1000 FT ABOVE HIM BUT ONLY 2400 FT HORIZLY. I FEEL THIS WAS A LITTLE CLOSE, BUT NOT IN ANY DANGER. THE CTLR COULD HAVE EASILY CHANGED OUR RWYS, WHICH WOULD HAVE MADE A SAFER SITUATION. I AM RPTING THIS SO PERHAPS ADDITIONAL RULES MIGHT BE CONSIDERED WITH THIS PARTICULAR TYPE OF VISUAL APCH. IT DOESN'T MAKE GOOD SENSE TO CRISS-CROSS ACFT TO THE FINAL APCH COURSE.

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.