Narrative:

I was cleared to land runway 28L, left downwind at pattern altitude (1000 ft). The other aircraft was cleared to takeoff runway 10L, right turn. Wind was reported calm, runways 28 in use on ATIS. I don't know why runway 10 was in use. The other aircraft was advised that I was downwind for runway 28L landing and acknowledged, then turned right crosswind, across my path, which would have been ok given our speed and distance. Then he turned right downwind at pattern altitude right into me. I had to take evasive action to miss him. 1) we should not have been using opposite runways at the same time. 2) the tower should have had him extend his upwind until safe to turn. 3) I don't think the other aircraft was cleared for a right downwind departure, but even if he was he should have had the sense not to turn until above pattern altitude, especially when he knew I was there.

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Original NASA ASRS Text

Title: NMAC WITH OPPOSITE DIRECTION SAME ALT TFC IN TFC PATTERN AT MOD. TA GIVEN. TFC SIGHTED. EVASIVE ACTION TURN.

Narrative: I WAS CLRED TO LAND RWY 28L, L DOWNWIND AT PATTERN ALT (1000 FT). THE OTHER ACFT WAS CLRED TO TKOF RWY 10L, R TURN. WIND WAS RPTED CALM, RWYS 28 IN USE ON ATIS. I DON'T KNOW WHY RWY 10 WAS IN USE. THE OTHER ACFT WAS ADVISED THAT I WAS DOWNWIND FOR RWY 28L LNDG AND ACKNOWLEDGED, THEN TURNED R XWIND, ACROSS MY PATH, WHICH WOULD HAVE BEEN OK GIVEN OUR SPD AND DISTANCE. THEN HE TURNED R DOWNWIND AT PATTERN ALT RIGHT INTO ME. I HAD TO TAKE EVASIVE ACTION TO MISS HIM. 1) WE SHOULD NOT HAVE BEEN USING OPPOSITE RWYS AT THE SAME TIME. 2) THE TWR SHOULD HAVE HAD HIM EXTEND HIS UPWIND UNTIL SAFE TO TURN. 3) I DON'T THINK THE OTHER ACFT WAS CLRED FOR A R DOWNWIND DEP, BUT EVEN IF HE WAS HE SHOULD HAVE HAD THE SENSE NOT TO TURN UNTIL ABOVE PATTERN ALT, ESPECIALLY WHEN HE KNEW I WAS THERE.

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.