Narrative:

Aircraft X was approximately 5 miles northwest of the field when approach control approval-requested a right downwind entry for runway 25; capped 2;000 and above for other VFR arrival aircraft for runway 15L. I approved the request; as soon as traffic permitted I allowed aircraft X his VFR descent at pilot discretion when he was approximately 2 miles nne of the field. Aircraft Y was 5 miles south of the field; eastbound; on the visual approach for runway 25. I immediately recognized the conflict. I instructed aircraft X to turn base; at this time he was approximately 2.5 miles northeast of the field. I informed aircraft Y of the glider traffic and instructed him to execute a 5 mile left base; at this time aircraft Y was approximately 5 southeast of the field. Aircraft Y asked if he needed to extend; I said affirmative; enter a 5 mile left base. Aircraft Y immediately turned inbound for a 3 mile left base. Aircraft X was established on a 2 mile final and at 80 kts. I instructed aircraft X to go around; he responded unable due to his engine being shut down. I then told aircraft Y to go around; climb and maintain 3;000; fly heading 255. Aircraft Y read back his instructions and began to climb. I then coordinated with approach control; aircraft Y was on the standard missed and coming back to him for re-sequence; approach control requested a 200 heading. I issued the 200 heading to aircraft Y and told him to contact departure. I thought aircraft Y had started turning and I switched him; but he was not turning. I realized he was heading into a much higher MVA. I told aircraft Y he needed to start his turn to 200; that he was entering an MVA of 5700 feet but he had already switched frequencies. Adequate initial spacing and sequence provided by approach controller. Compliance from the aircraft Y pilot to enter a 5 mile left base. Compliance from aircraft Y pilot to take assigned headings. Ensuring the pilot is physically turning to assigned heading to avoid conflict prior to frequency change.

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Original NASA ASRS Text

Title: SBA Tower controllers reported miscommunication with pilot resulted in entering a higher MVA.

Narrative: Aircraft X was approximately 5 Miles NW of the field when Approach Control approval-requested a right downwind entry for Runway 25; capped 2;000 and above for other VFR arrival aircraft for Runway 15L. I approved the request; as soon as traffic permitted I allowed Aircraft X his VFR descent at pilot discretion when he was approximately 2 Miles NNE of the field. Aircraft Y was 5 Miles south of the field; eastbound; on the visual approach for Runway 25. I immediately recognized the conflict. I instructed Aircraft X to turn Base; at this time he was approximately 2.5 Miles NE of the field. I informed Aircraft Y of the glider traffic and instructed him to execute a 5 Mile left base; at this time Aircraft Y was approximately 5 SE of the field. Aircraft Y asked if he needed to extend; I said affirmative; enter a 5 Mile left base. Aircraft Y immediately turned inbound for a 3 Mile left base. Aircraft X was established on a 2 Mile final and at 80 kts. I instructed Aircraft X to go around; he responded unable due to his engine being shut down. I then told Aircraft Y to go around; climb and maintain 3;000; fly heading 255. Aircraft Y read back his instructions and began to climb. I then coordinated with Approach Control; Aircraft Y was on the Standard Missed and coming back to him for re-sequence; Approach Control requested a 200 heading. I issued the 200 heading to Aircraft Y and told him to contact departure. I thought Aircraft Y had started turning and I switched him; but he was not turning. I realized he was heading into a much higher MVA. I told Aircraft Y he needed to start his turn to 200; that he was entering an MVA of 5700 feet but he had already switched frequencies. Adequate initial spacing and sequence provided by approach controller. Compliance from the Aircraft Y pilot to enter a 5 Mile left base. Compliance from Aircraft Y pilot to take assigned headings. Ensuring the pilot is physically turning to assigned heading to avoid conflict prior to frequency change.

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.