General aviation pilot on an RNAV approach runway 31 to sun described some apparent confusion on the...

Narrative:

While making the RNAV runway 31 approach to sun; I spotted the runway just prior to initiating a missed approach. The reported visibility was 3/4 mile but the in flight visibility was significantly better. There were no clouds and hence no ceiling. I advised the controller that I had the airport in sight and would circle to land. He told me that I could not land since the visibility was below minimums. I responded that that wasn't true and that I could land since I had good contact with both the airport and the surrounding terrain. In an effort to be helpful he then issued a special VFR clearance. I continued my circling maneuver and landed uneventfully. After landing he asked me for my estimate of the visibility and I estimated it at 1 1/4 mile. It actually must have been much better since I could see the entire runway even on my base leg. My concern and the reason for the report is that it was very distracting to have this conversation at a very flight critical moment and to have to quickly determine if the controller was correct. Since circling minimums were published and the visibility appeared adequate; I believe I made the correct decision. I know the controller was also trying to be helpful by issuing the special VFR clearance but my understanding is that I didn't need it and that it must be requested by the pilot. Again; although the controller was clearly trying to help me; it was very distracting to have to have an unnecessary conversation at that moment. If this possible situation were to arise again; I would advise the tower controller of my intentions well ahead of time so that any difference of opinion could be resolved at a less critical time.

Original NASA ASRS Text

Title: General Aviation pilot on an RNAV Approach Runway 31 to SUN described some apparent confusion on the part of ATC regarding the minimums required for the procedure; adding the Controllers questions were very untimely.

Narrative: While making the RNAV Runway 31 Approach to SUN; I spotted the runway just prior to initiating a missed approach. The reported visibility was 3/4 mile but the in flight visibility was significantly better. There were no clouds and hence no ceiling. I advised the Controller that I had the airport in sight and would circle to land. He told me that I could not land since the visibility was below minimums. I responded that that wasn't true and that I could land since I had good contact with both the airport and the surrounding terrain. In an effort to be helpful he then issued a Special VFR clearance. I continued my circling maneuver and landed uneventfully. After landing he asked me for my estimate of the visibility and I estimated it at 1 1/4 mile. It actually must have been much better since I could see the entire runway even on my base leg. My concern and the reason for the report is that it was very distracting to have this conversation at a very flight critical moment and to have to quickly determine if the Controller was correct. Since circling minimums were published and the visibility appeared adequate; I believe I made the correct decision. I know the Controller was also trying to be helpful by issuing the Special VFR clearance but my understanding is that I didn't need it and that it must be requested by the pilot. Again; although the Controller was clearly trying to help me; it was very distracting to have to have an unnecessary conversation at that moment. If this possible situation were to arise again; I would advise the tower controller of my intentions well ahead of time so that any difference of opinion could be resolved at a less critical time.

Data retrieved from NASA's ASRS site as of July 2013 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.

Attributes
ACN	1030552
Time
Date	201208
Local Time Of Day	1801-2400
Place
Locale Reference	SUN.Airport
State Reference	ID
Environment
Light	Daylight
Aircraft 1
Make Model Name	PA-34-200 Seneca I
Operating Under FAR Part	Part 91
Flight Phase	Final Approach
Route In Use	None
Flight Plan	IFR
Person 1
Function	Single Pilot Pilot Flying
Qualification	Flight Crew Instrument Flight Crew Flight Instructor Flight Crew Commercial Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 5 Flight Crew Total 5000 Flight Crew Type 500
Events
Anomaly	ATC Issue All Types

General aviation pilot on an RNAV approach runway 31 to sun described some apparent confusion on the part of ATC regarding the minimums required for the procedure; adding the controllers questions were very untimely.