Narrative:

From approximately XA37Z to XA40Z at 5000 ft talking to approach control; I think we were right around the shoreline for a right downwind to runway 19R at sna. I was slowing; so my throttles were at idle and we were level at 5000 ft. I had flaps 1 degree and was about 190-200 KTS. We got an RA to 'descend; descend.' I immediately pushed the nose over to a 1500-2000 ft rate of descent; leveling off at 4500 ft. We did not get a TA prior to the RA. We did not get any traffic alert from the controller. The first indication of traffic was an RA. After leveling at 4500 ft; we informed the controller that we got an RA from an aircraft that was at 5400 ft. I don't know if the other aircraft was descending or level; in ATC control or not. The copilot said that he did get a visual on a king air after we got the RA. We then asked ATC if they wanted us to climb back up to 5000 ft. He said yes; and we did so. Approach control handed us off to the tower at sna. We are now on right downwind to base for runway 19R. My first officer is looking out his side window toward the landing runway and at his approach plate. I was looking outside and ahead of the aircraft when all of a sudden; a large orange balloon with what looked like blue writing on it and a rope hanging from the bottom; filled the windshield. It scared the hell out of me! I yelled and ducked. It looked like it hit us or came so close that the air flow carried it over the top of the cockpit. My first officer saw it out of the corner of his eye and saw the large shadow that was cast over the cockpit. He immediately notified the tower controller. This balloon event scared me so much that I was still shaking when we arrived at the gate.

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Original NASA ASRS Text

Title: A320 ARR TO SNA WITH SCT AT 5000 FT EXPERIENCED TCAS RA WITH UNREPORTED TFC; THEN; ON TWR FREQ; EXPERIENCED CONFLICT WITH UNREPORTED BALLOON.

Narrative: FROM APPROX XA37Z TO XA40Z AT 5000 FT TALKING TO APCH CTL; I THINK WE WERE RIGHT AROUND THE SHORELINE FOR A R DOWNWIND TO RWY 19R AT SNA. I WAS SLOWING; SO MY THROTTLES WERE AT IDLE AND WE WERE LEVEL AT 5000 FT. I HAD FLAPS 1 DEG AND WAS ABOUT 190-200 KTS. WE GOT AN RA TO 'DSND; DSND.' I IMMEDIATELY PUSHED THE NOSE OVER TO A 1500-2000 FT RATE OF DSCNT; LEVELING OFF AT 4500 FT. WE DID NOT GET A TA PRIOR TO THE RA. WE DID NOT GET ANY TFC ALERT FROM THE CTLR. THE FIRST INDICATION OF TFC WAS AN RA. AFTER LEVELING AT 4500 FT; WE INFORMED THE CTLR THAT WE GOT AN RA FROM AN ACFT THAT WAS AT 5400 FT. I DON'T KNOW IF THE OTHER ACFT WAS DSNDING OR LEVEL; IN ATC CTL OR NOT. THE COPLT SAID THAT HE DID GET A VISUAL ON A KING AIR AFTER WE GOT THE RA. WE THEN ASKED ATC IF THEY WANTED US TO CLB BACK UP TO 5000 FT. HE SAID YES; AND WE DID SO. APCH CTL HANDED US OFF TO THE TWR AT SNA. WE ARE NOW ON R DOWNWIND TO BASE FOR RWY 19R. MY FO IS LOOKING OUT HIS SIDE WINDOW TOWARD THE LNDG RWY AND AT HIS APCH PLATE. I WAS LOOKING OUTSIDE AND AHEAD OF THE ACFT WHEN ALL OF A SUDDEN; A LARGE ORANGE BALLOON WITH WHAT LOOKED LIKE BLUE WRITING ON IT AND A ROPE HANGING FROM THE BOTTOM; FILLED THE WINDSHIELD. IT SCARED THE HELL OUT OF ME! I YELLED AND DUCKED. IT LOOKED LIKE IT HIT US OR CAME SO CLOSE THAT THE AIR FLOW CARRIED IT OVER THE TOP OF THE COCKPIT. MY FO SAW IT OUT OF THE CORNER OF HIS EYE AND SAW THE LARGE SHADOW THAT WAS CAST OVER THE COCKPIT. HE IMMEDIATELY NOTIFIED THE TWR CTLR. THIS BALLOON EVENT SCARED ME SO MUCH THAT I WAS STILL SHAKING WHEN WE ARRIVED AT THE GATE.

Data retrieved from NASA's ASRS site as of May 2009 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.