Narrative:

Aircraft X was on a localizer approach to runway 27R. This is a circling approach. Aircraft X was asked if he wanted a straight in or circle to the runway. I informed the aircraft that a circle was standard. Aircraft X asked to circle. Aircraft X was instructed to maintain 1900 and to report over the numbers for runway 27R. Aircraft X was then instructed to plan to circle 2 miles south to make a 3 1/2 base turn for runway 27R. At the numbers; aircraft X was instructed to circle south (as indicated on the approach plates). 2 miles south aircraft X was instructed to continue descent. Then I noticed aircraft X turning west. Aircraft X was instructed to turn east via a left turn for a left base runway 27R. Aircraft X stated that they thought they were going to runway 09L. Once on left downwind runway 27R aircraft X was told about traffic inside of him for runway 27L and to turn a 2 1/2 mile base and cleared to land runway 27R. Aircraft X reported traffic in sight and cleared to land. Aircraft X cut off aircraft Y turning a 1 mile base then asked who the traffic was on his right. Aircraft X was informed that the traffic was for runway 27L and was going around. I then reconfirmed that aircraft X was cleared to land runway 27R. While aircraft X was turning west he was within 1.4 NM and 700 feet of another aircraft on approach to myf on an ILS approach. That aircraft was not in my control.this is a circling approach and although I have had no problems with other aircraft conducting this maneuver I could have reconfirmed with aircraft X that they were to circle east for left downwind runway 27R.after sitting with the atm and hearing the pilots thoughts and expectations for the approach it sounded like the pilot was expecting to land on another runway other that one advertised. The pilot stated that at their airport it is was common for an aircraft to make an approach to one runway then circle to a runway most aligned with the wind. When it was pointed out that the approach into see did not actually go to a runway that they were to circle to the runway in use the pilot seemed to have more clarity. This is a good opportunity to teach pilots that due to terrain some airports have other than standard approaches.

Google
 

Original NASA ASRS Text

Title: SEE Local Controller and the involved pilots reported of confusion and an airborne conflict while on a circling approach.

Narrative: Aircraft X was on a LOC approach to Runway 27R. This is a circling approach. Aircraft X was asked if he wanted a straight in or circle to the runway. I informed the aircraft that a circle was standard. Aircraft X asked to circle. Aircraft X was instructed to maintain 1900 and to report over the numbers for Runway 27R. Aircraft X was then instructed to plan to circle 2 miles south to make a 3 1/2 base turn for runway 27R. At the numbers; Aircraft X was instructed to circle south (as indicated on the approach plates). 2 miles south Aircraft X was instructed to continue descent. Then I noticed Aircraft X turning west. Aircraft X was instructed to turn east via a left turn for a left base Runway 27R. Aircraft X stated that they thought they were going to Runway 09L. Once on left downwind Runway 27R Aircraft X was told about traffic inside of him for Runway 27L and to turn a 2 1/2 mile base and cleared to land Runway 27R. Aircraft X reported traffic in sight and cleared to land. Aircraft X cut off Aircraft Y turning a 1 mile base then asked who the traffic was on his right. Aircraft X was informed that the traffic was for Runway 27L and was going around. I then reconfirmed that Aircraft X was cleared to land Runway 27R. While Aircraft X was turning west he was within 1.4 NM and 700 feet of another aircraft on approach to MYF on an ILS approach. That aircraft was not in my control.This is a circling approach and although I have had no problems with other aircraft conducting this maneuver I could have reconfirmed with Aircraft X that they were to circle east for left downwind runway 27R.After sitting with the ATM and hearing the pilots thoughts and expectations for the approach it sounded like the pilot was expecting to land on another runway other that one advertised. The pilot stated that at their airport it is was common for an aircraft to make an approach to one runway then circle to a runway most aligned with the wind. When it was pointed out that the approach into SEE did not actually go to a runway that they were to circle to the runway in use the pilot seemed to have more clarity. This is a good opportunity to teach pilots that due to terrain some airports have other than standard approaches.

Data retrieved from NASA's ASRS site 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.