Narrative:

I was on duty as the local controller at riverside tower. WX was - X5H. Traffic was moderate. Runway 27 was the active. The ILS approach serves runway 9. Small aircraft X was on the ILS approach, on tower frequency, at the OM. I cleared him for a low approach to runway 9. Small aircraft Y then reported left downwind for runway 27 for touch and go, which I approved. It appeared at this time that small aircraft X would complete his approach before the opposite direction touch and go would be a factor. Small transport U called for departure, was told to hold short of the runway for landing traffic. Aircraft V called ready as did aircraft west. Both aircraft were told to hold and sequenced for departure. Helicopter Z called for departure from FBO to go to the #16A. Timing was perfect. I cleared him to the VOR check point to hold for landing traffic. He was approaching the VOR check point as small aircraft Y passed on his touch and go. I cleared Z to cross runway 27 direct to the numbers 16A. Then I remembered small aircraft X on the approach. He was now on short final to runway 9 with Y climbing directly toward him. I told X to start a climbing right turn, but before he responded Y turned left to avoid him. Small aircraft X made a slight left turn followed by a right turn for the missed approach. Opposite direction traffic is a hazard at any time and with distrs can get out of control very quickly. I normally advise aircraft on the approach, at the OM, to make a climbing right turn to paradise VORTAC when advised due to opposite direction traffic. But at this time I thought it would be no factor. Why did this happen? I was distracted buy other traffic. Riverside traffic has increased about 30 percent in the past yr. Mostly helicopter operations which tend to divide our attention. How to prevent this from happening again? It's time to stop this opposite direction practice VFR approachs. Or at least have them break off the approach on 2 mi final. It might have helped if the instructor in small aircraft X was looking out the window.

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Original NASA ASRS Text

Title: LTSS AND NMAC BTWN 2 SMA ACFT IN TFC PATTERN. OPAL ERROR.

Narrative: I WAS ON DUTY AS THE LCL CTLR AT RIVERSIDE TWR. WX WAS - X5H. TFC WAS MODERATE. RWY 27 WAS THE ACTIVE. THE ILS APCH SERVES RWY 9. SMA X WAS ON THE ILS APCH, ON TWR FREQ, AT THE OM. I CLRED HIM FOR A LOW APCH TO RWY 9. SMA Y THEN RPTED L DOWNWIND FOR RWY 27 FOR TOUCH AND GO, WHICH I APPROVED. IT APPEARED AT THIS TIME THAT SMA X WOULD COMPLETE HIS APCH BEFORE THE OPPOSITE DIRECTION TOUCH AND GO WOULD BE A FACTOR. SMT U CALLED FOR DEP, WAS TOLD TO HOLD SHORT OF THE RWY FOR LNDG TFC. ACFT V CALLED READY AS DID ACFT W. BOTH ACFT WERE TOLD TO HOLD AND SEQUENCED FOR DEP. HELI Z CALLED FOR DEP FROM FBO TO GO TO THE #16A. TIMING WAS PERFECT. I CLRED HIM TO THE VOR CHK POINT TO HOLD FOR LNDG TFC. HE WAS APCHING THE VOR CHK POINT AS SMA Y PASSED ON HIS TOUCH AND GO. I CLRED Z TO CROSS RWY 27 DIRECT TO THE NUMBERS 16A. THEN I REMEMBERED SMA X ON THE APCH. HE WAS NOW ON SHORT FINAL TO RWY 9 WITH Y CLBING DIRECTLY TOWARD HIM. I TOLD X TO START A CLBING R TURN, BUT BEFORE HE RESPONDED Y TURNED L TO AVOID HIM. SMA X MADE A SLIGHT L TURN FOLLOWED BY A R TURN FOR THE MISSED APCH. OPPOSITE DIRECTION TFC IS A HAZARD AT ANY TIME AND WITH DISTRS CAN GET OUT OF CTL VERY QUICKLY. I NORMALLY ADVISE ACFT ON THE APCH, AT THE OM, TO MAKE A CLBING R TURN TO PARADISE VORTAC WHEN ADVISED DUE TO OPPOSITE DIRECTION TFC. BUT AT THIS TIME I THOUGHT IT WOULD BE NO FACTOR. WHY DID THIS HAPPEN? I WAS DISTRACTED BUY OTHER TFC. RIVERSIDE TFC HAS INCREASED ABOUT 30 PERCENT IN THE PAST YR. MOSTLY HELI OPS WHICH TEND TO DIVIDE OUR ATTN. HOW TO PREVENT THIS FROM HAPPENING AGAIN? IT'S TIME TO STOP THIS OPPOSITE DIRECTION PRACTICE VFR APCHS. OR AT LEAST HAVE THEM BREAK OFF THE APCH ON 2 MI FINAL. IT MIGHT HAVE HELPED IF THE INSTRUCTOR IN SMA X WAS LOOKING OUT THE WINDOW.

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.