Narrative:

The [flight] crew called from ZZZ and said that the #2 hydraulic system was reading 100 percent in the 'off' position; but reads correct pressure when in the 'on' position. I then deferred the #2 hydraulic accumulator as in the past. The aircraft flew one leg and when maintenance went to fix it; they found there was no # 2 accumulator installed.the accumulator had been removed based on an airworthiness directive (ad). The flight crew and I were unaware that they had been removed. And the MEL did not state it. We took the aircraft off-line and fixed the problem. That same day a note was put into the MEL stating the two accumulators had been removed from the aircraft.

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Original NASA ASRS Text

Title: A Line Mechanic reports he deferred the #2 Hydraulic System Accumulator on a company CRJ-CL65 aircraft under their MEL procedures after the flight crew reported incorrect pressure readings. Downline Maintenance reported #2 Hydraulic Accumulator had been previously removed per an Airworthiness Directive (AD); but their MEL had not been updated.

Narrative: The [flight] crew called from ZZZ and said that the #2 Hydraulic System was reading 100 percent in the 'OFF' position; but reads correct pressure when in the 'ON' position. I then deferred the #2 Hydraulic Accumulator as in the past. The aircraft flew one leg and when Maintenance went to fix it; they found there was no # 2 Accumulator installed.The Accumulator had been removed based on an Airworthiness Directive (AD). The flight crew and I were unaware that they had been removed. And the MEL did not state it. We took the aircraft off-line and fixed the problem. That same day a note was put into the MEL stating the two accumulators had been removed from the aircraft.

Data retrieved from NASA's ASRS site as of July 2013 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.