AN ACR B737 FLC HAS SEVERAL PWR INTERRUPTIONS WHILE ON GND PWR. THEY DO MANAGE TO ALIGN THE INERTIAL REF SYS AND DO NOT BELIEVE THAT THE PWR PROBS AFFECTED THESE SYS. HOWEVER; ONCE AIRBORNE; THE FLC EXPERIENCES A SERIES OF FAILURES OF IRS DRIVEN SYS AND HAVE TO RETURN.

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AT THE BOARDING GATE; THE GND PWR FLUCTUATED SEVERAL TIMES WHILE THE APU WAS STARTING AND THE IRS'S WERE ALIGNED. I TURNED OFF THE GND PWR AND ALLOWED THE APU TO FINISH STARTING; WHICH I PLACED ON THE ACFT BUSSES. WE CHKED THE ALIGNMENT AND HAD NO PROBS WITH ANY PERCEIVABLE SYS MALFUNCTIONS. IN POS ON THE RWY; ON THE TKOF STATUS PAGE IT SAID: POS ENT. THIS PROMPT LED US TO CHK THE 'POS REF' PAGE; WHICH SHOWED LAST AND CURRENT POS. THESE DIGITS AFTER A CLOSE CHK BY THE FO AND I AGREED. THIS TELLS ME THAT THE IRS'S ARE ALIGNED. AFTER TKOF ON A HDG OF S FROM RWY 8; THE FO'S ADI FAILED; AND MINE DID NOT. AFTER TURNING FURTHER SW WE DID NOT HAVE EITHER ADI OR HDG INFO. WE WERE IMC AT THIS POINT AND DECIDED TO CLB TO OUR ASSIGNED ALT OF 15000 FT. I SELECTED ATT ON THE IRS'S WHICH RESTORED OUR ADI'S. THE FO HAD BEEN USING THE STANDBY ADI. INSTEAD OF TYPING IN THE HDG ON THE FMC OR IRS'S I ASKED FOR A NO GYRO VECTOR TO VMC CONDITIONS WHICH WE FOLLOWED WITH THE HELP OF ABQ TWR TO A VISUAL APCH TO RWY 8 AT ABQ. I NOTICED THROUGHOUT THIS THAT OUR NAV RADIOS WERE INOP. I HAD TUNED ZUNI VOR ON BOTH SIDES AND DID NOT GET A WARNING RED FLAG ON OUR RMI'S. THE NEEDLES WERE PARKED AT THE 9 O'CLOCK POS. THIS SAME SCENARIO WITH THE RMI'S WHEN ABQ WAS TUNED OCCURRED. WE LANDED WITH NO FURTHER FAILURES OR PROBS. I TAXIED TO THE GATE STILL NOTING THE RMI'S WHICH WERE STILL TUNED TO ABQ AND STILL INDICATING 'FAILED.' AT THE GATE I DID A FULL ALIGNMENT AND ALL OF THESE SUBSEQUENT FAILURES DISAPPEARED. ALL SYS OPERATING NORMALLY. WE OBTAINED A NEW RELEASE AND WX. FLEW TO PHX WITH NO FURTHER PROBS. SUPPLEMENTAL INFO FROM ACN 387297: THE PROB WAS RPTED TO MAINT IN PHX WHO FOUND THE SYS WORKING OK.