Narrative:

The aircraft had not flown for 13 days and had been in a hangar on its next flight the takeoff was aborted due no a/south on first officer's instrument. Mechanics found a pitot line disconnected. Reconnected, leak check ok and aircraft departed. On climb out captain's ivsi read 7 also captain's altitude ALS and mach read low. On arrival in gig, mechanic found static hose disconnected from captain's ivsi, reconnected hose and signed off other problems as symptoms of same problem. I took the aircraft on next flight. After takeoff ivsi operated normally, however, captain's ALS, altitude, mach, standby altitude, TAS read low in eze found drain plug loose on lt tunnel lower 41. Retorqued and tested ok. Since they had found a problem and corrected it and lead check was ok, we took the aircraft back to gig. After takeoff we had the same problems only much more pronounced ALS 20 KTS off altimeter in excess of 2000 off. We checked the alternate static source but did not help. On inspection in rio, mechanic found captain mor/altitude static source valve lines leaking and static leak check ok. On next flight (gig-jfk) problem was fixed. Numerous times when I have a problem, whether a gyro losing power or a central air data computer not working, mechanics has the option of reseating the instrument, swapping with the other on the aircraft or cleaning a cannon plug and releasing the aircraft only to have the problem resurface. This can continue seemingly indefinitely. So long as mechanic is performed and signed off the air crew is legal to take the airplane. Legal, but is it safe. It's not easy to turn down an aircraft after being signed off as airworthy. Wonder if an airline in bankruptcy is more prone to careless errors and poor mechanics.

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Original NASA ASRS Text

Title: ACR WDG HAS SERIES OF FLT INSTRUMENT PROBLEMS AFTER EXTENDED MAINTENANCE ACTIVITY.

Narrative: THE ACFT HAD NOT FLOWN FOR 13 DAYS AND HAD BEEN IN A HANGAR ON ITS NEXT FLT THE TKOF WAS ABORTED DUE NO A/S ON FO'S INSTRUMENT. MECHS FOUND A PITOT LINE DISCONNECTED. RECONNECTED, LEAK CHK OK AND ACFT DEPARTED. ON CLBOUT CAPT'S IVSI READ 7 ALSO CAPT'S ALT ALS AND MACH READ LOW. ON ARR IN GIG, MECH FOUND STATIC HOSE DISCONNECTED FROM CAPT'S IVSI, RECONNECTED HOSE AND SIGNED OFF OTHER PROBS AS SYMPTOMS OF SAME PROB. I TOOK THE ACFT ON NEXT FLT. AFTER TKOF IVSI OPERATED NORMALLY, HOWEVER, CAPT'S ALS, ALT, MACH, STANDBY ALT, TAS READ LOW IN EZE FOUND DRAIN PLUG LOOSE ON LT TUNNEL LOWER 41. RETORQUED AND TESTED OK. SINCE THEY HAD FOUND A PROB AND CORRECTED IT AND LEAD CHK WAS OK, WE TOOK THE ACFT BACK TO GIG. AFTER TKOF WE HAD THE SAME PROBS ONLY MUCH MORE PRONOUNCED ALS 20 KTS OFF ALTIMETER IN EXCESS OF 2000 OFF. WE CHKED THE ALTERNATE STATIC SOURCE BUT DID NOT HELP. ON INSPECTION IN RIO, MECH FOUND CAPT MOR/ALT STATIC SOURCE VALVE LINES LEAKING AND STATIC LEAK CHK OK. ON NEXT FLT (GIG-JFK) PROB WAS FIXED. NUMEROUS TIMES WHEN I HAVE A PROB, WHETHER A GYRO LOSING PWR OR A CENTRAL AIR DATA COMPUTER NOT WORKING, MECHS HAS THE OPTION OF RESEATING THE INSTRUMENT, SWAPPING WITH THE OTHER ON THE ACFT OR CLEANING A CANNON PLUG AND RELEASING THE ACFT ONLY TO HAVE THE PROB RESURFACE. THIS CAN CONTINUE SEEMINGLY INDEFINITELY. SO LONG AS MECH IS PERFORMED AND SIGNED OFF THE AIR CREW IS LEGAL TO TAKE THE AIRPLANE. LEGAL, BUT IS IT SAFE. IT'S NOT EASY TO TURN DOWN AN ACFT AFTER BEING SIGNED OFF AS AIRWORTHY. WONDER IF AN AIRLINE IN BANKRUPTCY IS MORE PRONE TO CARELESS ERRORS AND POOR MECHS.

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.