What was found
ETOPS SIGNIFICANT SYS - ATB - ON T/O RUN, ABOVE 100 KTS, CAPT'S IAS WENT ROD/INOP/UNRELIABLE. TRANSFERED CONTROL. BOTH F/O & ISIS ACCURATE. CAPTS ALTIMETER OK CHANGED AIRDATA TO "CAPT ON 3" - DISPLAY OK. OK TO CONT IAW MEL 34-10-1B. PLACARDED AND ENTERED ON LIDS. DMI 41137 T/S FOUND NR1 ADIRU INOP. SWAPPED NR1 AND NR2 ADIRU. PLACARDED NR2 ADIRU INOP. NR1 ADIRU GROUND OPS CHECK OK IAW AMM 34-12-34. OPEN