Narrative:

Got to B737 aircraft X for our flight to ZZZZ. Had write-up on standby ADI. Maintenance worked on part, unable to fix (this is the new integrated standby ADI, all-in-one unit). No parts in ZZZ. Had 1 in ZZZ1 and ZZZ2, but not at crew base. This is a common failure type item and I cannot believe we don't have several in ZZZ. Maintenance and I both said no way, but if this situation exists on a common type part, I wonder if it also exists across the rest of the parts inventory, point being there will be pressure on both maintenance and pilots to accept degraded aircraft for 'on-time' pressure. We took the delay and inconvenienced numerous passenger, including out of country connecting passenger who had to overnight due to insufficient parts.

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Original NASA ASRS Text

Title: B737-700 TRIP WAS DELAYED IN ORDER TO REPLACE AN SAI. REPLACEMENT PARTS WERE UNAVAILABLE AT THE LARGEST STATION WHERE THIS ACFT IS OPERATED.

Narrative: GOT TO B737 ACFT X FOR OUR FLT TO ZZZZ. HAD WRITE-UP ON STANDBY ADI. MAINT WORKED ON PART, UNABLE TO FIX (THIS IS THE NEW INTEGRATED STANDBY ADI, ALL-IN-ONE UNIT). NO PARTS IN ZZZ. HAD 1 IN ZZZ1 AND ZZZ2, BUT NOT AT CREW BASE. THIS IS A COMMON FAILURE TYPE ITEM AND I CANNOT BELIEVE WE DON'T HAVE SEVERAL IN ZZZ. MAINT AND I BOTH SAID NO WAY, BUT IF THIS SIT EXISTS ON A COMMON TYPE PART, I WONDER IF IT ALSO EXISTS ACROSS THE REST OF THE PARTS INVENTORY, POINT BEING THERE WILL BE PRESSURE ON BOTH MAINT AND PLTS TO ACCEPT DEGRADED ACFT FOR 'ON-TIME' PRESSURE. WE TOOK THE DELAY AND INCONVENIENCED NUMEROUS PAX, INCLUDING OUT OF COUNTRY CONNECTING PAX WHO HAD TO OVERNIGHT DUE TO INSUFFICIENT PARTS.

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.