Narrative:

Upon reaching the ZZZ civic center, I contacted ZZZ tower and requested landing. I was told to proceed direct toward ZZZ tower and and report 1 mi out. When I reported 1 mi out, I was instructed to cross the airport at or above 500' and cross behind the small aircraft X on final approach to runway 28L. At that time, I informed ZZZ tower that I had no visibility sighting of the small aircraft X. He informed me the small aircraft X was just touching down on the numbers of runway 28L. I told him I now had a visual sighting. ZZZ tower requested I expedite my crossing behind the small aircraft. At this time a flight nurse seated on the left side of the helicopter and I saw a single engine small aircraft Y at our altitude and in 9 O'clock position and less than 1/4 mi and flying runway 28 heading. I made an evasive left turn and descent to avoid the aircraft. The tower at the same time notified me of the conflicting traffic and requested I pass behind the small aircraft Y. ZZZ tower informed the small aircraft Y pilot that he had not been cleared for the low approach to runway 28L. After landing I called ZZZ tower and asked about the incident. My question was, had I missed a traffic report to me about aircraft operating in traffic pattern? He informed me I had not been told about the small aircraft Y. Small aircraft Y had just departed runway 28L and had requested a low approach to runway 28. The tower told the small aircraft Y pilot that they would accommodate his request and that the tower would call his left base turn. The small aircraft Y made the approach west/O tower permission. The tower controller said that they would be talking to tower supervisor about the small aircraft Y pilot's actions. The WX at ZZZ reported to FSS was: sky obscured, 25000' broken, 3 mi with fog and haze. Temperature 61 degrees F, dew point 45 degrees, wind calm, altimeter 2999', haze obscuring 3/10 of sky.

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Original NASA ASRS Text

Title: CLOSE PROX GA SMA HELICOPTER AND GA SMA IN ZZZ ATA.

Narrative: UPON REACHING THE ZZZ CIVIC CENTER, I CONTACTED ZZZ TWR AND REQUESTED LNDG. I WAS TOLD TO PROCEED DIRECT TOWARD ZZZ TWR AND AND RPT 1 MI OUT. WHEN I RPTED 1 MI OUT, I WAS INSTRUCTED TO CROSS THE ARPT AT OR ABOVE 500' AND CROSS BEHIND THE SMA X ON FINAL APCH TO RWY 28L. AT THAT TIME, I INFORMED ZZZ TWR THAT I HAD NO VIS SIGHTING OF THE SMA X. HE INFORMED ME THE SMA X WAS JUST TOUCHING DOWN ON THE NUMBERS OF RWY 28L. I TOLD HIM I NOW HAD A VISUAL SIGHTING. ZZZ TWR REQUESTED I EXPEDITE MY XING BEHIND THE SMA. AT THIS TIME A FLT NURSE SEATED ON THE LEFT SIDE OF THE HELI AND I SAW A SINGLE ENG SMA Y AT OUR ALT AND IN 9 O'CLOCK POS AND LESS THAN 1/4 MI AND FLYING RWY 28 HDG. I MADE AN EVASIVE LEFT TURN AND DSCNT TO AVOID THE ACFT. THE TWR AT THE SAME TIME NOTIFIED ME OF THE CONFLICTING TFC AND REQUESTED I PASS BEHIND THE SMA Y. ZZZ TWR INFORMED THE SMA Y PLT THAT HE HAD NOT BEEN CLRED FOR THE LOW APCH TO RWY 28L. AFTER LNDG I CALLED ZZZ TWR AND ASKED ABOUT THE INCIDENT. MY QUESTION WAS, HAD I MISSED A TFC RPT TO ME ABOUT ACFT OPERATING IN TFC PATTERN? HE INFORMED ME I HAD NOT BEEN TOLD ABOUT THE SMA Y. SMA Y HAD JUST DEPARTED RWY 28L AND HAD REQUESTED A LOW APCH TO RWY 28. THE TWR TOLD THE SMA Y PLT THAT THEY WOULD ACCOMMODATE HIS REQUEST AND THAT THE TWR WOULD CALL HIS LEFT BASE TURN. THE SMA Y MADE THE APCH W/O TWR PERMISSION. THE TWR CTLR SAID THAT THEY WOULD BE TALKING TO TWR SUPVR ABOUT THE SMA Y PLT'S ACTIONS. THE WX AT ZZZ RPTED TO FSS WAS: SKY OBSCURED, 25000' BROKEN, 3 MI WITH FOG AND HAZE. TEMP 61 DEGS F, DEW POINT 45 DEGS, WIND CALM, ALTIMETER 2999', HAZE OBSCURING 3/10 OF SKY.

Data retrieved from NASA's ASRS site as of August 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.