Narrative:

After landing on runway 7 at den and leaving the runway, waited for the tower to give us the ground control frequency. When they did not contact us I queried them as to the frequency they wished us to use. It was at this time that approach told us to go back to tower and ask them. This is when we realized we were still on approach and had not contacted the tower for landing clearance. I then went over to the tower frequency and asked for ground frequency. Our airline has a 1000 ft callout and the PF responds 'cleared to land.' I as the PF, I believed we had been cleared to land because the last contact I remember was something to the effect that we were '#2 to land behind a heavy B777, caution wake turbulence.' I believed we had also been cleared to land at that time. This was the error in that the PNF had not actually gotten it from tower. A contributing problem to this event is the fact that approach told us approximately 15 mi out to contact the tower at the marker and gave us the frequency. Since you don't do this until later, it is easy to forget by the time you get to the marker since by then you are focused on a stabilized approach and not talking on the radio (a human factors issue). Approach should have you go immediately to tower when they no longer need you on their frequency, not at a later time.

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Original NASA ASRS Text

Title: MLG FLC LANDS WITHOUT CLRNC. GIVEN SWITCH TO TWR AT MARKER CLRNC WHEN 15 MI OUT.

Narrative: AFTER LNDG ON RWY 7 AT DEN AND LEAVING THE RWY, WAITED FOR THE TWR TO GIVE US THE GND CTL FREQ. WHEN THEY DID NOT CONTACT US I QUERIED THEM AS TO THE FREQ THEY WISHED US TO USE. IT WAS AT THIS TIME THAT APCH TOLD US TO GO BACK TO TWR AND ASK THEM. THIS IS WHEN WE REALIZED WE WERE STILL ON APCH AND HAD NOT CONTACTED THE TWR FOR LNDG CLRNC. I THEN WENT OVER TO THE TWR FREQ AND ASKED FOR GND FREQ. OUR AIRLINE HAS A 1000 FT CALLOUT AND THE PF RESPONDS 'CLRED TO LAND.' I AS THE PF, I BELIEVED WE HAD BEEN CLRED TO LAND BECAUSE THE LAST CONTACT I REMEMBER WAS SOMETHING TO THE EFFECT THAT WE WERE '#2 TO LAND BEHIND A HVY B777, CAUTION WAKE TURB.' I BELIEVED WE HAD ALSO BEEN CLRED TO LAND AT THAT TIME. THIS WAS THE ERROR IN THAT THE PNF HAD NOT ACTUALLY GOTTEN IT FROM TWR. A CONTRIBUTING PROB TO THIS EVENT IS THE FACT THAT APCH TOLD US APPROX 15 MI OUT TO CONTACT THE TWR AT THE MARKER AND GAVE US THE FREQ. SINCE YOU DON'T DO THIS UNTIL LATER, IT IS EASY TO FORGET BY THE TIME YOU GET TO THE MARKER SINCE BY THEN YOU ARE FOCUSED ON A STABILIZED APCH AND NOT TALKING ON THE RADIO (A HUMAN FACTORS ISSUE). APCH SHOULD HAVE YOU GO IMMEDIATELY TO TWR WHEN THEY NO LONGER NEED YOU ON THEIR FREQ, NOT AT A LATER TIME.

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.