Narrative:

After the flight engineer obtained the ATIS for us at dtw, we decided to request a visual approach to runway 27. The captain (PNF) asked if center could call ahead with our request for runway 27R, runway 21R was the active on the ATIS. Center called us back with a clearance down to 12000 ft and said detroit ok'ed runway 27R. As we approached 12000 ft, center told us to contact metropolitan tower and gave us the tower frequency. The captain checked us in saying we were leveling at 12000 ft with the field in sight. Tower said 'roger air carrier X, you're cleared to land runway 27R.' I remarked to the captain that I guess we're cleared out of 12000 ft for the approach. He said 'I guess so' and we continued our descent into detroit. Approaching 8000 ft, tower asked us to contact approach. I continued monitoring tower, while the captain used the other VHF to contact approach. Approach gueried us if we had clearance for an approach. The captain responded that tower had cleared us to land, to which approach said 'yes, but I never gave you approach clearance.' he then cleared us to 3000 ft and told us to call the field. The captain called the field in sight, we were cleared the visual approach, and then switched back to tower. Tower reconfirmed our landing clearance. Even though it is not unusual for us to experience approach/tower/ground consolidated into one during the night, I rediscovered the old maxim of 'when in doubt, query the controller.' it did seem unusual for tower to clear us to land without going through the ritual of being cleared 1) out of an altitude, and 2) for an approach. While we expressed our thoughts in the cockpit we never clarified things with ATC. During the quiet of night operations it's easy to relax your guard, but I found the importance of always hearing the standard phrases and clrncs.

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Original NASA ASRS Text

Title: ACR X UNAUTH DSCNT FROM ASSIGNED ALT. PLTDEV.

Narrative: AFTER THE FE OBTAINED THE ATIS FOR US AT DTW, WE DECIDED TO REQUEST A VISUAL APCH TO RWY 27. THE CAPT (PNF) ASKED IF CTR COULD CALL AHEAD WITH OUR REQUEST FOR RWY 27R, RWY 21R WAS THE ACTIVE ON THE ATIS. CTR CALLED US BACK WITH A CLRNC DOWN TO 12000 FT AND SAID DETROIT OK'ED RWY 27R. AS WE APCHED 12000 FT, CTR TOLD US TO CONTACT METRO TWR AND GAVE US THE TWR FREQ. THE CAPT CHKED US IN SAYING WE WERE LEVELING AT 12000 FT WITH THE FIELD IN SIGHT. TWR SAID 'ROGER ACR X, YOU'RE CLRED TO LAND RWY 27R.' I REMARKED TO THE CAPT THAT I GUESS WE'RE CLRED OUT OF 12000 FT FOR THE APCH. HE SAID 'I GUESS SO' AND WE CONTINUED OUR DSCNT INTO DETROIT. APCHING 8000 FT, TWR ASKED US TO CONTACT APCH. I CONTINUED MONITORING TWR, WHILE THE CAPT USED THE OTHER VHF TO CONTACT APCH. APCH GUERIED US IF WE HAD CLRNC FOR AN APCH. THE CAPT RESPONDED THAT TWR HAD CLRED US TO LAND, TO WHICH APCH SAID 'YES, BUT I NEVER GAVE YOU APCH CLRNC.' HE THEN CLRED US TO 3000 FT AND TOLD US TO CALL THE FIELD. THE CAPT CALLED THE FIELD IN SIGHT, WE WERE CLRED THE VISUAL APCH, AND THEN SWITCHED BACK TO TWR. TWR RECONFIRMED OUR LNDG CLRNC. EVEN THOUGH IT IS NOT UNUSUAL FOR US TO EXPERIENCE APCH/TWR/GND CONSOLIDATED INTO ONE DURING THE NIGHT, I REDISCOVERED THE OLD MAXIM OF 'WHEN IN DOUBT, QUERY THE CTLR.' IT DID SEEM UNUSUAL FOR TWR TO CLR US TO LAND WITHOUT GOING THROUGH THE RITUAL OF BEING CLRED 1) OUT OF AN ALT, AND 2) FOR AN APCH. WHILE WE EXPRESSED OUR THOUGHTS IN THE COCKPIT WE NEVER CLARIFIED THINGS WITH ATC. DURING THE QUIET OF NIGHT OPS IT'S EASY TO RELAX YOUR GUARD, BUT I FOUND THE IMPORTANCE OF ALWAYS HEARING THE STANDARD PHRASES AND CLRNCS.

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.