ACR CLBS ABOVE ASSIGNED ALT WHEN DISTR BY TCASII RA.

Narrative

WHILE CLBING THROUGH FL260 FTW CENTER INFORMED US TO LEVEL AT FL270 IN 1 MIN OR LESS FOR TFC. AT FL269 WHILE LEVELING FOR FL270 THE CAPT INQUIRED THE COPLT ABOUT A TFC PROX SYMBOL APCHING FROM 11 O'CLOCK. ATC ISSUED A TFC RPT; HOWEVER THE ALT PORTION OF THE RPT WAS BLOCKED BY THE TCASII AUDIO WARNING 'TFC; TFC.' WHILE LEVELING AT FL270 WE RECEIVED A RA WARNING. FOCUS SHIFTED FROM THE ALTIMETER TO THE IVSI TO EXECUTE THE RA COMMAND. INTERPRETATION WAS DELAYED BY THE KNOWLEDGE OF TFC BELOW; A DELAY IN THE APPEARANCE OF THE IVSI'S ADVISORY LIGHTS; THE SUNS WASHOUT AFFECT OF THE IVSI LIGHTS WHEN THEY DID APPEAR; AND THE RA'S RELATIVE ALT SEPARATION OF 09+ WHEN WE WERE 100 FT LOW OF ASSIGNED ALT. WE CONTINUED OUR CURRENT STEADY STATE FLT CONDITIONS (SLIGHT CLB) DURING INTERPRETATION; THEN FOLLOWED THE TCASII LEVEL COMMAND. THE ACFT BALLOONED ABOVE THE ASSIGNED ALT DURING THE MANEUVER. ATC INQUIRED ABOUT OUR ALT AFTER WE MADE THE NECESSARY CORRECTION. SUPPLEMENTAL INFO FROM ACN 197104. INTERPRETATION WAS DELAYED BY THE KNOWLEDGE OF TFC BELOW AND WHAT SEEMED TO BE A DELAY IN THE IVSI TCASII LIGHTS APPEARING. THE TCASII COMMAND WAS FOLLOWED. AT THE SAME TIME; I SPOTTED THE OTHER ACFT VISUALLY; AND DETERMINED HE WAS NOT A HAZARD.