Narrative:

We were cleared the profile descent into denver, the approach check was complete. I noticed traffic in our 11 O'clock and called it out, at first it appeared to be an medium large transport paralleling, however, it began to track right. I asked captain to solicit information on the traffic and just when approach called traffic 12 O'clock 1 NM altitude readout 14500 ft unverified in an excited tone. We all 3 were watching the small transport go directly overhead of us, the captain commented to atca guess on his real altitude. Then we commented amongst ourselves how we should have been notified of this traffic sooner. The altitude alerter went off at 12600 ft. We climbed immediately back to our cleared to 13000 ft. Nothing further was said. Routine landing. I feel that we should have been told much sooner of the conflict. The traffic was hard to distinguish with the sun behind the small transport. It could have been a large aircraft far away or a small aircraft close by. We were tracking approximately 135 degree and I estimated our conflicts track to be 240 degree. The altitude deviation occurred because we all 3 were looking at the traffic (not uncommon when determining whether or not traffic is in conflict) and were shaken by the lack of notification in a timely manner. When traffic passed overhead at 1000 ft or less it always seems much less.

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Original NASA ASRS Text

Title: ACR HAS CONFLICT WITH SMT WHILE ON PROFILE DSCNT. ALT DEV.

Narrative: WE WERE CLRED THE PROFILE DSCNT INTO DENVER, THE APCH CHK WAS COMPLETE. I NOTICED TFC IN OUR 11 O'CLOCK AND CALLED IT OUT, AT FIRST IT APPEARED TO BE AN MLG PARALLELING, HOWEVER, IT BEGAN TO TRACK R. I ASKED CAPT TO SOLICIT INFO ON THE TFC AND JUST WHEN APCH CALLED TFC 12 O'CLOCK 1 NM ALT READOUT 14500 FT UNVERIFIED IN AN EXCITED TONE. WE ALL 3 WERE WATCHING THE SMT GO DIRECTLY OVERHEAD OF US, THE CAPT COMMENTED TO ATCA GUESS ON HIS REAL ALT. THEN WE COMMENTED AMONGST OURSELVES HOW WE SHOULD HAVE BEEN NOTIFIED OF THIS TFC SOONER. THE ALT ALERTER WENT OFF AT 12600 FT. WE CLBED IMMEDIATELY BACK TO OUR CLRED TO 13000 FT. NOTHING FURTHER WAS SAID. ROUTINE LNDG. I FEEL THAT WE SHOULD HAVE BEEN TOLD MUCH SOONER OF THE CONFLICT. THE TFC WAS HARD TO DISTINGUISH WITH THE SUN BEHIND THE SMT. IT COULD HAVE BEEN A LARGE ACFT FAR AWAY OR A SMALL ACFT CLOSE BY. WE WERE TRACKING APPROX 135 DEG AND I ESTIMATED OUR CONFLICTS TRACK TO BE 240 DEG. THE ALT DEV OCCURRED BECAUSE WE ALL 3 WERE LOOKING AT THE TFC (NOT UNCOMMON WHEN DETERMINING WHETHER OR NOT TFC IS IN CONFLICT) AND WERE SHAKEN BY THE LACK OF NOTIFICATION IN A TIMELY MANNER. WHEN TFC PASSED OVERHEAD AT 1000 FT OR LESS IT ALWAYS SEEMS MUCH LESS.

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.