Narrative:

I was relieving the approach controller, who had one aircraft, small transport X. The controller I was relieving pointed out that small transport X was maneuvering on his own navigation for descent and had been told to report the airport in sight for a visual approach. I noticed that the flight progress strip showed the aircraft descending to 130 and that the aircraft's mode C indicated 105. I pointed this out to the controller I was relieving. He was surprised, and told me the aircraft had not been issued lower than 130. I pointed out the deviation to the supervisor who asked that the pilot call the tower after landing. The pilot did, and the supervisor pointed out the error to the pilot, who admitted his mistake. I feel that the major contributing factor in this incident is the pilot's over-familiar attitude concerning the tower. The pilot handles the local XXX franchise's ground operation and every morning, without fail, calls the tower to ask if we have the inbound on the XXX aircraft. We, without fail, tell him what he wants to know. This information is available to him through XXX dispatch, but he insists on calling us. In addition, this pilot flies a balloon (hot air type) several times a week, departing from within the air traffic area. He advises as prior to launch (which is good), but calls several times thereafter (up to 10 calls) and asks 'what's the wind doing?' this information is available from the NWS (located on the airport), but we always oblige. On the day of the incident, the pilot called the tower for a clearance into minneapolis center's airspace, a clearance he should have filed with an FSS. However, we obliged. I feel that all of our efforts to 'bend over backwards' contributed to this pilot's lackadaisical attitude, resulting in his deviation.

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Original NASA ASRS Text

Title: FLT CREW DESCENDED FROM ASSIGNED ALT WITHOUT AUTHORIZATION. PLT DEVIATION.

Narrative: I WAS RELIEVING THE APCH CTLR, WHO HAD ONE ACFT, SMT X. THE CTLR I WAS RELIEVING POINTED OUT THAT SMT X WAS MANEUVERING ON HIS OWN NAVIGATION FOR DSCNT AND HAD BEEN TOLD TO REPORT THE ARPT IN SIGHT FOR A VISUAL APCH. I NOTICED THAT THE FLT PROGRESS STRIP SHOWED THE ACFT DESCENDING TO 130 AND THAT THE ACFT'S MODE C INDICATED 105. I POINTED THIS OUT TO THE CTLR I WAS RELIEVING. HE WAS SURPRISED, AND TOLD ME THE ACFT HAD NOT BEEN ISSUED LOWER THAN 130. I POINTED OUT THE DEVIATION TO THE SUPVR WHO ASKED THAT THE PLT CALL THE TWR AFTER LNDG. THE PLT DID, AND THE SUPVR POINTED OUT THE ERROR TO THE PLT, WHO ADMITTED HIS MISTAKE. I FEEL THAT THE MAJOR CONTRIBUTING FACTOR IN THIS INCIDENT IS THE PLT'S OVER-FAMILIAR ATTITUDE CONCERNING THE TWR. THE PLT HANDLES THE LCL XXX FRANCHISE'S GND OPERATION AND EVERY MORNING, WITHOUT FAIL, CALLS THE TWR TO ASK IF WE HAVE THE INBND ON THE XXX ACFT. WE, WITHOUT FAIL, TELL HIM WHAT HE WANTS TO KNOW. THIS INFO IS AVAILABLE TO HIM THROUGH XXX DISPATCH, BUT HE INSISTS ON CALLING US. IN ADDITION, THIS PLT FLIES A BALLOON (HOT AIR TYPE) SEVERAL TIMES A WEEK, DEPARTING FROM WITHIN THE ATA. HE ADVISES AS PRIOR TO LAUNCH (WHICH IS GOOD), BUT CALLS SEVERAL TIMES THEREAFTER (UP TO 10 CALLS) AND ASKS 'WHAT'S THE WIND DOING?' THIS INFO IS AVAILABLE FROM THE NWS (LOCATED ON THE ARPT), BUT WE ALWAYS OBLIGE. ON THE DAY OF THE INCIDENT, THE PLT CALLED THE TWR FOR A CLRNC INTO MINNEAPOLIS CENTER'S AIRSPACE, A CLRNC HE SHOULD HAVE FILED WITH AN FSS. HOWEVER, WE OBLIGED. I FEEL THAT ALL OF OUR EFFORTS TO 'BEND OVER BACKWARDS' CONTRIBUTED TO THIS PLT'S LACKADAISICAL ATTITUDE, RESULTING IN HIS DEVIATION.

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.