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|
Attributes | |
ACN | 1662336 |
Time | |
Date | 201907 |
Local Time Of Day | 0601-1200 |
Place | |
Locale Reference | ZZZ.Airport |
State Reference | US |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Make Model Name | EMB ERJ 145 ER/LR |
Operating Under FAR Part | Part 121 |
Flight Phase | Parked Taxi |
Flight Plan | IFR |
Component | |
Aircraft Component | Engine Air Pneumatic Ducting |
Person 1 | |
Function | Captain Pilot Flying |
Qualification | Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine |
Events | |
Anomaly | Aircraft Equipment Problem Less Severe Deviation - Procedural MEL Deviation - Procedural Published Material / Policy Deviation - Procedural Maintenance |
Narrative:
The aircraft that was brought to us had a maintenance write up just previous to our flight for a bleed 1 leak during taxi; it was cleared with a 'performed ops (operation) reset of bleed sys (system) per mx (maintenance) control'. Upon taxiing out we experienced the same bleed leak issue. Maintenance control initially wanted us to MEL the #1 pack. Since the flight deck temperature had already reached 35C with both packs cooling the aircraft. I felt it unwise to accept the aircraft with just the number #2 pack providing cooling (the #2 pack predominantly provides cool air to the cabin).after returning to the gate and de-planing the passengers we did an engine run and taxi in order to troubleshoot the issue. The engine run was performed with bleed #1 selected off and no issues were noted at that time. Contract maintenance initially deferred the bleed system via MEL 36-xx-xx-X; securing the lh engine bleed air system closed. At the recommendation of the contract mechanic; we attempted to perform an engine run at the gate with both the engines. On the first attempt to start engine #2 (which we typically start first) the APU automatically shut itself down (there are multiple write-ups in the maintenance logbooks for this APU issue) midway through the engine start sequence; this caused an aborted start of the #2 engine due to a hot start condition. I entered the APU discrepancy in the aircraft logbook and we restarted the APU per maintenance control's request; dry motored engine #2 and restarted it in accordance with the QRH. Engine #2 started normally on the second attempt with the APU operating normally. We then started engine #1; everything indicated normal and no bleed #1 leak was noted. Still at the gate; with the maintenance paperwork being completed; we encountered another bleed leak warning. Only this time; no engines were running (just the APU) and pack #1 was selected in the off position. Maintenance control instructed the contract mechanic to undo the previously performed bleed #1 MEL. The corrective action was noted as 'found leak to be caused by pack 1. Bleed valve secured open MEL cleared. Placard removed' he was then instructed to MEL pack #1 instead. I feel that the pack #1 MEL did not make sense as pack #1 had been de-selected prior to the last bleed #1 leak warning (each warning we encountered resulted in a master warning; EICAS message and the leak inscription on the bleed selector illuminating). Maintenance control mentioned that this was part of the 'trouble shooting'; which did not sit well with me. I felt uneasy with maintenance control's multiple application of MEL's as a trouble shooting solution; particularly when the choice was made to MEL a system that was not operable when the final bleed leak occurred. To my knowledge; no inspection was ever made or noted in the maintenance log for any additional damage that may have occurred as a result of the bleed leak. Considering how catastrophic a bleed leak could be in-flight and with all above mentioned factors; both my first officer and I felt the safest course of action was to refuse the aircraft.
Original NASA ASRS Text
Title: ERJ145 Captain reported multiple MEL's and aircraft system failures at gate forced flight crew to refuse aircraft.
Narrative: The aircraft that was brought to us had a maintenance write up just previous to our flight for a Bleed 1 Leak during taxi; it was cleared with a 'performed ops (operation) reset of bleed sys (system) per mx (Maintenance) control'. Upon taxiing out we experienced the same bleed leak issue. Maintenance Control initially wanted us to MEL the #1 Pack. Since the flight deck temperature had already reached 35C with both packs cooling the aircraft. I felt it unwise to accept the aircraft with just the number #2 pack providing cooling (the #2 pack predominantly provides cool air to the cabin).After returning to the gate and de-planing the passengers we did an engine run and taxi in order to troubleshoot the issue. The engine run was performed with Bleed #1 selected off and no issues were noted at that time. Contract Maintenance initially deferred the bleed system via MEL 36-XX-XX-X; securing the LH engine bleed air system closed. At the recommendation of the Contract Mechanic; we attempted to perform an engine run at the gate with both the engines. On the first attempt to start engine #2 (which we typically start first) the APU automatically shut itself down (there are multiple write-ups in the maintenance logbooks for this APU issue) midway through the engine start sequence; this caused an aborted start of the #2 engine due to a hot start condition. I entered the APU discrepancy in the aircraft logbook and we restarted the APU per Maintenance Control's request; dry motored engine #2 and restarted it in accordance with the QRH. Engine #2 started normally on the second attempt with the APU operating normally. We then started engine #1; everything indicated normal and no bleed #1 leak was noted. Still at the gate; with the maintenance paperwork being completed; we encountered another bleed leak warning. Only this time; no engines were running (just the APU) and Pack #1 was selected in the off position. Maintenance Control instructed the Contract Mechanic to undo the previously performed Bleed #1 MEL. The corrective action was noted as 'Found leak to be caused by Pack 1. Bleed Valve secured open MEL cleared. Placard Removed' He was then instructed to MEL Pack #1 instead. I feel that the Pack #1 MEL did not make sense as Pack #1 had been de-selected prior to the last Bleed #1 leak Warning (Each warning we encountered resulted in a Master Warning; EICAS message and the LEAK inscription on the Bleed Selector illuminating). Maintenance Control mentioned that this was part of the 'trouble shooting'; which did not sit well with me. I felt uneasy with Maintenance Control's multiple application of MEL's as a trouble shooting solution; particularly when the choice was made to MEL a system that was not operable when the final bleed leak occurred. To my knowledge; no inspection was ever made or noted in the maintenance log for any additional damage that may have occurred as a result of the bleed leak. Considering how catastrophic a bleed leak could be in-flight and with all above mentioned factors; both my First Officer and I felt the safest course of action was to refuse the aircraft.
Data retrieved from NASA's ASRS site 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.