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|
Attributes | |
ACN | 1496967 |
Time | |
Date | 201711 |
Local Time Of Day | 1801-2400 |
Place | |
Locale Reference | ZZZ.Airport |
State Reference | US |
Environment | |
Flight Conditions | VMC |
Light | Night |
Aircraft 1 | |
Make Model Name | EMB ERJ 170/175 ER/LR |
Operating Under FAR Part | Part 121 |
Flight Phase | Climb |
Flight Plan | IFR |
Component | |
Aircraft Component | Pneumatic System |
Person 1 | |
Function | Captain Pilot Not Flying |
Qualification | Flight Crew Air Transport Pilot (ATP) |
Events | |
Anomaly | Aircraft Equipment Problem Less Severe |
Narrative:
I was a captain involved in an air return to [departure airport]. My decision to return was due to several compounding factors. While climbing through approximately FL220; 'bleed 2 fail' presented on the EICAS. It is of note that bleed 1 had previously been deferred and was not operational for this flight. The APU was selected off after takeoff and cannot supply bleed air above 15;000 ft. This left the aircraft temporarily without a bleed source for the ecs (environmental control system) system. The aircraft cabin climb rate increased from its normal 300-400 fpm climb to approximately 1000 fpm. In the moment; with ATC approval; we elected [to] level off; then began a descent; then slowed the airplane down and took a vector. During this time; the first officer flew the plane and operated the radios while I ran the QRH for bleed 2 fail. After running the QRH; we were able to clear the bleed 2 fail message. The QRH states that if the message clears; to continue with normal operations. If bleed 1 had not already been deferred and this bleed 2 were the only issue to factor in; all would be copacetic for continuing. However; on top of at least one; if not two compromised bleed sources; a look at the ecs synoptic page revealed that the crossbleed valve (although no EICAS message was indicating its failure) remained closed and thusly pack 1 was off. Both pack 1 and the xbleed button on the overhead panel were pressed in (non-illuminated). This added to my concerns as proper operation of the xbleed valve was a crucial stipulation of our existing bleed 1 MEL procedure. At this point; I phone patched with dispatch and maintenance control to broaden our circle; then made the decision to return to [departure airport] and conducted the tasks required for an air return.further compounding the situation was that earlier in the day; with this same airplane (and same deferred bleed 1); we also encountered mechanical issues with the bleed 2 system as well. We were operating our 1st of 4 legs to start our day. We conducted an ecs off takeoff into icing conditions (engine & wing) with the APU on for takeoff. Shortly after takeoff we were alerted via EICAS caution of a bleed 2 overpress. We ran the QRH and the caution cleared. Based on our results from following the QRH; it stated to continue with normal operations; so we continued. Once in [destination]; as directed by the mechanical irregularities action chart - inflight; we contacted maintenance control and placed an entry in the logbook. Maintenance control initially wanted to defer bleed 2 but we reminded them that bleed 1 was already deferred. They elected to send a mechanic to the airplane to run some static engine runs/tests. Bleed system 2 passed the requisite testing and we were cleared by maintenance control and conducted [the next flight] after a delay. This leg (2nd of 4) went by uneventfully.below is a list of the compounding factors that contributed to our decision to return to [departure airport] rather than completing the flight as planned:1. Bleed 2 fail on climb2. Previous mechanical issues that day with bleed 23. Bleed 1 already inoperative per MEL4. Confusing and/or undesired state of crossbleed valve after bleed 2 fail event5. APU bleed limited to 15;000' (fuel requirements made this a prohibitive option to rely on APU bleed for backup ecs bleed source)6. Mountainous terrain at night potentially limiting our options for descent if further necessary7. Loss of anti-icing capability in the event of bleed 1 & 2 failure
Original NASA ASRS Text
Title: EMB-175 Captain reported they were dispatched with pneumatic bleed Number 1 deferred inoperative and decided to return to departure airport after experiencing loss of pneumatic bleed Number 2.
Narrative: I was a Captain involved in an air return to [departure airport]. My decision to return was due to several compounding factors. While climbing through approximately FL220; 'BLEED 2 FAIL' presented on the EICAS. It is of note that Bleed 1 had previously been deferred and was not operational for this flight. The APU was selected off after takeoff and cannot supply bleed air above 15;000 ft. This left the aircraft temporarily without a bleed source for the ECS (Environmental Control System) system. The aircraft cabin climb rate increased from its normal 300-400 fpm climb to approximately 1000 fpm. In the moment; with ATC approval; we elected [to] level off; then began a descent; then slowed the airplane down and took a vector. During this time; the First Officer flew the plane and operated the radios while I ran the QRH for BLEED 2 FAIL. After running the QRH; we were able to clear the BLEED 2 FAIL message. The QRH states that if the message clears; to continue with normal operations. If Bleed 1 had not already been deferred and this BLEED 2 were the only issue to factor in; all would be copacetic for continuing. However; on top of at least one; if not two compromised bleed sources; a look at the ECS synoptic page revealed that the crossbleed valve (although no EICAS message was indicating its failure) remained closed and thusly PACK 1 was off. Both PACK 1 and the XBLEED button on the overhead panel were pressed in (non-illuminated). This added to my concerns as proper operation of the XBLEED valve was a crucial stipulation of our existing BLEED 1 MEL procedure. At this point; I phone patched with Dispatch and Maintenance Control to broaden our circle; then made the decision to return to [departure airport] and conducted the tasks required for an air return.Further compounding the situation was that earlier in the day; with this same airplane (and same deferred Bleed 1); we also encountered mechanical issues with the BLEED 2 system as well. We were operating our 1st of 4 legs to start our day. We conducted an ECS Off takeoff into icing conditions (ENG & Wing) with the APU on for takeoff. Shortly after takeoff we were alerted via EICAS Caution of a BLEED 2 OVERPRESS. We ran the QRH and the caution cleared. Based on our results from following the QRH; it stated to continue with normal operations; so we continued. Once in [destination]; as directed by the Mechanical Irregularities Action Chart - Inflight; we contacted Maintenance Control and placed an entry in the logbook. Maintenance Control initially wanted to defer BLEED 2 but we reminded them that BLEED 1 was already deferred. They elected to send a mechanic to the airplane to run some static engine runs/tests. Bleed System 2 passed the requisite testing and we were cleared by Maintenance Control and conducted [the next flight] after a delay. This leg (2nd of 4) went by uneventfully.Below is a list of the compounding factors that contributed to our decision to return to [departure airport] rather than completing the flight as planned:1. Bleed 2 Fail on climb2. Previous mechanical issues that day with Bleed 23. Bleed 1 already inoperative per MEL4. Confusing and/or undesired state of Crossbleed valve after Bleed 2 fail event5. APU Bleed limited to 15;000' (fuel requirements made this a prohibitive option to rely on APU Bleed for backup ECS Bleed source)6. Mountainous terrain at night potentially limiting our options for descent if further necessary7. Loss of anti-icing capability in the event of BLEED 1 & 2 failure
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.