Narrative:

At approximately XA17 aircraft Y reported inbound to crg on a visual approach to runway 5. The aircraft was observed to be approximately 10 mi south of crg on the d-brite and was instructed to report a right base to runway 5. Also inbound was military X from the southeast VFR with instruction to report a right base for runway 5. At approximately XA18, nga reported a left downwind for runway 32 and was cleared to land. At approximately a XA18 a military helicopter called requesting hover taxi instructions for departure and was told to hover taxi to runway 5 sod. At approximately XA18 military X reported the right base to runway 5 and was visually observed 1 mi south and cleared to land. At approximately XA19 aircraft Y reported a 2 mi right base and was told not in sight, traffic is a helicopter also on the right base. Approximately 5 seconds later aircraft Y was visually observed and passed the helicopter off the left side of the helicopter at a high rate of speed. I again called traffic asking the military X if he had the aircraft ahead in sight. The military X pilot reported traffic was in sight. I instructed the military X pilot that he was now #2 for landing and to follow the cessna. The military X pilot reported that he was inside the cessna and would like to proceed direct to runway 5 sod for landing. I approved this and instructed aircraft Y to fly through final and make a left 270 degree turn back to final for spacing. Both aircraft landed safely. I was advised by jax approach that after doing a data reduction, aircraft Y's airspeed was around 190 KTS all the way in. I believe the pilot of this aircraft wanted to be #1 for landing and did not want to throttle back to follow the helicopter. Aircraft Y traveled well faster than most centurions inbound to land at a fairly busy VFR tower. The speed of the aircraft threw off my own judgment concerning who would be traffic for whom in that after initial contact with aircraft Y, I did not look at the d-brite again as I was looking out the window visually locating aircraft. I shall pay more attention to aircraft speed in the future when I'm able to determine it.

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Original NASA ASRS Text

Title: SMA ENTERING BASE LEG PASSES IN CLOSE PROX TO A MIL HELI ALSO ON A BASE RESULTING IN AN NMAC.

Narrative: AT APPROX XA17 ACFT Y RPTED INBOUND TO CRG ON A VISUAL APCH TO RWY 5. THE ACFT WAS OBSERVED TO BE APPROX 10 MI S OF CRG ON THE D-BRITE AND WAS INSTRUCTED TO RPT A R BASE TO RWY 5. ALSO INBOUND WAS MIL X FROM THE SE VFR WITH INSTRUCTION TO RPT A R BASE FOR RWY 5. AT APPROX XA18, NGA RPTED A L DOWNWIND FOR RWY 32 AND WAS CLRED TO LAND. AT APPROX A XA18 A MIL HELI CALLED REQUESTING HOVER TAXI INSTRUCTIONS FOR DEP AND WAS TOLD TO HOVER TAXI TO RWY 5 SOD. AT APPROX XA18 MIL X RPTED THE R BASE TO RWY 5 AND WAS VISUALLY OBSERVED 1 MI S AND CLRED TO LAND. AT APPROX XA19 ACFT Y RPTED A 2 MI R BASE AND WAS TOLD NOT IN SIGHT, TFC IS A HELI ALSO ON THE R BASE. APPROX 5 SECONDS LATER ACFT Y WAS VISUALLY OBSERVED AND PASSED THE HELI OFF THE L SIDE OF THE HELI AT A HIGH RATE OF SPD. I AGAIN CALLED TFC ASKING THE MIL X IF HE HAD THE ACFT AHEAD IN SIGHT. THE MIL X PLT RPTED TFC WAS IN SIGHT. I INSTRUCTED THE MIL X PLT THAT HE WAS NOW #2 FOR LNDG AND TO FOLLOW THE CESSNA. THE MIL X PLT RPTED THAT HE WAS INSIDE THE CESSNA AND WOULD LIKE TO PROCEED DIRECT TO RWY 5 SOD FOR LNDG. I APPROVED THIS AND INSTRUCTED ACFT Y TO FLY THROUGH FINAL AND MAKE A L 270 DEG TURN BACK TO FINAL FOR SPACING. BOTH ACFT LANDED SAFELY. I WAS ADVISED BY JAX APCH THAT AFTER DOING A DATA REDUCTION, ACFT Y'S AIRSPD WAS AROUND 190 KTS ALL THE WAY IN. I BELIEVE THE PLT OF THIS ACFT WANTED TO BE #1 FOR LNDG AND DID NOT WANT TO THROTTLE BACK TO FOLLOW THE HELI. ACFT Y TRAVELED WELL FASTER THAN MOST CENTURIONS INBOUND TO LAND AT A FAIRLY BUSY VFR TWR. THE SPD OF THE ACFT THREW OFF MY OWN JUDGMENT CONCERNING WHO WOULD BE TFC FOR WHOM IN THAT AFTER INITIAL CONTACT WITH ACFT Y, I DID NOT LOOK AT THE D-BRITE AGAIN AS I WAS LOOKING OUT THE WINDOW VISUALLY LOCATING ACFT. I SHALL PAY MORE ATTN TO ACFT SPD IN THE FUTURE WHEN I'M ABLE TO DETERMINE IT.

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.