Narrative:

Refusal for flight. This aircraft has safety concerns associated with its maintenance history. Specifically; the most recent log history shows the following: 1) IRU 2 position deviation '7.4 miles'. Note: the A320 flight manual specifies the maximum acceptable deviation is 5.0 NM. 2) 2 write up showing elac [elevator aileron computer] #2 faults and FMGC faults. I consulted with maintenance control regarding the current log information as well as previous log history going back some two weeks. Moreover; I had personally experienced failures with this aircraft on a previous flight. I explained to maintenance control that a previous maintenance control controller told me that elac 2 was faulting due to incorrect navigation data. It is also my understanding that the IRU/elac 2 problem can also be tied to the FMGC. I pointed out that a week ago a crew experienced both fmgcs locking up on a 10-mile final and that they lost all navigation; weight and cg data. I also pointed out to maintenance control that the original navigation problems appear to have begun occurring about three weeks ago with reports of the aircraft dropping out of the navigation mode and into heading mode. Several other reports similar in nature were subsequently made. These reports showed large map shifts and faulty irus. Additional messages in the mcdu scratch pad include 'check IRS 2 & 3' and 'IR3 check FM position'. Additionally; I personally experienced these navigation malfunctions two weeks ago during a coast to coast flight. Over den the aircraft dropped out of the navigation mode and into heading mode. There was a map shift and the map display on the captain's and first officer's pfd showed a slight disagreement. We also received a scratch pad message indicating a disagreement between IRS 1 and 2. After checking the positions enroute it was apparent that the #2 IRU was off by 4.5 NM and the # 1 was off by over 3 NM. The longer we flew the more these values went out of tolerance. Upon landing the #2 IRU was off by 6.2 NM and the #1 IRU was off by 4.8 NM. When we selected the cfds [centralized fault display system] enroute; it was showing elac #2 faults. Note: we did not get any elac ECAM messages. I refused this aircraft today for safety reasons; all of which were explained in detail to the dispatcher; maintenance control; two flight duty managers and followed up with subsequent discussions with flight managers at my home base. All of the above managers and pilots agreed with my position. I was assured by them that I followed proper protocol and my reasoning amply justified the refusal. Our passenger's safety is paramount. There seem to be new policies geared toward delaying overdue maintenance and coercing pilots into accepting aircraft with known safety related issues. It is disturbing that our company has allowed this aircraft to fly around for this long of a time period; treating repeat write-ups of interdependent systems with 'quick fix' system tests; essentially ignoring the complexity and severity of the problem. There is no excuse for not identifying and fixing this problem at its root cause; instead of using deferrals to keep the airplane flying. Obviously there is something very wrong to be causing the multitude of navigation deviations and the associated elac and FMGC issues. In my view; our company is putting both the crews and its passengers at unnecessary risk and are; in effect; covering up this maintenance issue with sign offs like; 'accomplished chronic review' and 'irus in tolerance' when our manuals state otherwise. This pencil whipping is another form of playing russian roulette with our safety. It would be one thing to lose all the navs and simply get radar vectors to fly an approach and land. Since the irus are tied to the elacs and fmgcs; however; a failure or disagreement of two irus could potentially put the aircraft into alternate law; and compromise rvsm airspace requirements. Again; let me point out the above crew experienced complete failureof both FMGC's on a 10 mile final just a week prior. The onerous log history and lack of creditable action speaks for itself.

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Original NASA ASRS Text

Title: An A320 Captain refused an aircraft with multiple chronic Navigation and Flight Control system AML write-ups that he felt were never adequately addressed by maintenance and improperly deferred.

Narrative: Refusal for Flight. This aircraft has safety concerns associated with its maintenance history. Specifically; the most recent log history shows the following: 1) IRU 2 position deviation '7.4 miles'. Note: the A320 Flight Manual specifies the maximum acceptable deviation is 5.0 NM. 2) 2 write up showing ELAC [ELevator Aileron Computer] #2 Faults and FMGC faults. I consulted with Maintenance Control regarding the current log information as well as previous log history going back some two weeks. Moreover; I had personally experienced failures with this aircraft on a previous flight. I explained to Maintenance Control that a previous Maintenance Control controller told me that ELAC 2 was faulting due to incorrect NAV data. It is also my understanding that the IRU/ELAC 2 problem can also be tied to the FMGC. I pointed out that a week ago a crew experienced both FMGCs locking up on a 10-mile final and that they lost ALL NAV; Weight and CG data. I also pointed out to Maintenance Control that the original NAV problems appear to have begun occurring about three weeks ago with reports of the aircraft dropping out of the NAV mode and into HDG mode. Several other reports similar in nature were subsequently made. These reports showed large map shifts and faulty IRUs. Additional messages in the MCDU scratch pad include 'check IRS 2 & 3' and 'IR3 Check FM Position'. Additionally; I personally experienced these Navigation malfunctions two weeks ago during a coast to coast flight. Over DEN the aircraft dropped out of the NAV mode and into HDG mode. There was a map shift and the map display on the Captain's and First Officer's PFD showed a slight disagreement. We also received a scratch pad message indicating a disagreement between IRS 1 and 2. After checking the positions enroute it was apparent that the #2 IRU was off by 4.5 NM and the # 1 was off by over 3 NM. The longer we flew the more these values went out of tolerance. Upon landing the #2 IRU was off by 6.2 NM and the #1 IRU was off by 4.8 NM. When we selected the CFDS [Centralized Fault Display System] enroute; it was showing ELAC #2 faults. Note: We did not get any ELAC ECAM messages. I refused this aircraft today for safety reasons; all of which were explained in detail to the dispatcher; Maintenance Control; two Flight Duty managers and followed up with subsequent discussions with Flight Managers at my home base. All of the above managers and pilots agreed with my position. I was assured by them that I followed proper protocol and my reasoning amply justified the refusal. Our passenger's safety is paramount. There seem to be new policies geared toward delaying overdue maintenance and coercing pilots into accepting aircraft with known safety related issues. It is disturbing that our company has allowed this aircraft to fly around for this long of a time period; treating repeat write-ups of interdependent systems with 'quick fix' system tests; essentially ignoring the complexity and severity of the problem. There is no excuse for NOT identifying and fixing this problem at its root cause; instead of using deferrals to keep the airplane flying. Obviously there is something very wrong to be causing the multitude of NAV deviations and the associated ELAC and FMGC issues. In my view; our company is putting both the crews and its passengers at unnecessary risk and are; in effect; covering up this maintenance issue with sign offs like; 'accomplished chronic review' and 'IRUs in tolerance' when our manuals state otherwise. This pencil whipping is another form of playing Russian roulette with our safety. It would be one thing to lose all the NAVs and simply get radar vectors to fly an approach and land. Since the IRUs are tied to the ELACs and FMGCs; however; a failure or disagreement of two IRUs could potentially put the aircraft into Alternate Law; and compromise RVSM airspace requirements. Again; let me point out the above crew experienced complete failureof both FMGC's on a 10 mile final just a week prior. The onerous log history and lack of creditable action speaks for itself.

Data retrieved from NASA's ASRS site as of April 2012 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.