Narrative:

Aircraft was climbing from FL290 to FL350. Leaving FL300-FL310, pilot reported executing 'a hard RA' for traffic. Aircraft descended back to approximately FL285. Only traffic anywhere nearby was 4 O'clock position at 20 NM or 12 O'clock position at 25 NM, at FL270 climbing to FL290 and FL330 respective. Pilot then reclbed to FL310, and received another 'hard RA.' upon further questioning, pilot reported traffic less than 200 ft above the first time, less than 400 ft the second time. Pilot reported RA occurred both times while climbing through FL300-FL310. Only possible anomaly was aircraft was directly over a radar site (jot). There was zero traffic, primary or otherwise, near aircraft. (Aircraft deviated approximately 3000 ft from assigned altitude.)

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Original NASA ASRS Text

Title: FLC OF A B737 DSNDED DURING CLB DUE TO TCASII RA. AFTER THE RA HAPPENED A SECOND TIME IN THE SAME ALT AREA, TOGETHER WITH ARTCC CTLR SHOWING NO TFC IN CLOSE PROX TO THEIR ACFT, FLC CONCLUDED THAT THE RA WAS A FALSE WARNING.

Narrative: ACFT WAS CLBING FROM FL290 TO FL350. LEAVING FL300-FL310, PLT RPTED EXECUTING 'A HARD RA' FOR TFC. ACFT DSNDED BACK TO APPROX FL285. ONLY TFC ANYWHERE NEARBY WAS 4 O'CLOCK POS AT 20 NM OR 12 O'CLOCK POS AT 25 NM, AT FL270 CLBING TO FL290 AND FL330 RESPECTIVE. PLT THEN RECLBED TO FL310, AND RECEIVED ANOTHER 'HARD RA.' UPON FURTHER QUESTIONING, PLT RPTED TFC LESS THAN 200 FT ABOVE THE FIRST TIME, LESS THAN 400 FT THE SECOND TIME. PLT RPTED RA OCCURRED BOTH TIMES WHILE CLBING THROUGH FL300-FL310. ONLY POSSIBLE ANOMALY WAS ACFT WAS DIRECTLY OVER A RADAR SITE (JOT). THERE WAS ZERO TFC, PRIMARY OR OTHERWISE, NEAR ACFT. (ACFT DEVIATED APPROX 3000 FT FROM ASSIGNED ALT.)

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.