EMB ERJ 170/175 ER/LR
Flight Crew Commercial
Confusion; Human-Machine Interface
Aircraft Equipment Problem Critical
Air Traffic Control Issued New Clearance; Flight Crew Diverted; Flight Crew Landed As Precaution; General Declared Emergency; General Maintenance Action
Aircraft
Approximately 25-30 minutes after departing and through our climb passing through about FL340; we got a FUEL FEED 1 FAULT EICAS message. I pulled up the Fuel Synoptic page to look at the system. We noticed that the fuel was slightly imbalanced so we placed the Crossfeed Valve to 'LOW 2' to balance the fuel load. Oddly enough; there was no associated advisory EICAS message when we performed this task. We followed the 'IN-FLIGHT' procedure for the FUEL FEED 1 FAULT message and did notice that the 'motive flow' system was not green and that the AC Pump 1 was being used. The message did remove and we continued with normal operations and monitored the system as the QRH procedure directed. As a precaution; the Captain gave me the airplane and radios while he contacted Dispatch/Maintenance. Maybe 2 minutes after returning from the discussion; he noticed that on the Fuel Synoptic page that the 'motive flow' system for Engine 2 was also not green and that the AC Pump 2 was now in use; however there was no EICAS message for this either. For some reason; the DC Electric Pump was also modulating between green and white (On/Off). As a precaution; we placed both AC Pumps for both sides of the fuel system to the 'ON' position to be sure that fuel was being provided to our engines. The Captain again relinquished the airplane and radios to me while he contacted Dispatch/Maintenance. When he returned; he informed me that we were to divert. I kept control of the airplane while he communicated our plans to ATC; the Flight Attendants; and the passengers. ATC gave us direct to the VOR and then direct to the airport with a descent to FL330. We then again safely transferred the aircraft controls. While we were preparing for the arrival (getting ATIS; getting our charts; and setting up our landing data); I noticed it was quickly getting hot so I pulled up the ECS Synoptic page on my side and pointed out that both engine bleed valves were closed and that our PACK's were off. However; on EICAS 1 in the CABIN PRESSURIZATION window; normal indications were being shown. At that very moment; both the Captain and I were sensing symptoms of hypoxia (light headed and tingling extremities) and we both quickly donned our oxygen masks and proceeded with an emergency descent. We declared an emergency with ATC and said that we needed to execute an emergency descent; so the Controller cleared us down to 11;000 FT. The Captain performed the descent maneuver while I performed the Emergency/Rapid Descent QRH procedure. The peculiarity of the descent was that the Cabin Altitude remained in parameters so according to the QRH; there was no need to deploy the Passenger Oxygen masks. Once we got down to 11;000 FT; we were able to remove our masks and we proceeded with our normal operations. ATC gave us the approach to expect and we were able to continue setting the landing data; verify the requirements in the QRH (landing speeds/distances based on landing weight); brief the approach; and then complete both the Descent and Approach checklists. For whatever reason; we did regain our PACK's once we were below 10;000 FT. As the Captain flew the approach; I cycled through the various synoptic pages to monitor all systems in the event of any other malfunctions i.e. with flap and/or gear extension. At this time we did notice also that on the Electric Synoptic page that AC BUS 2; TRU 2; and DC BUS 2 were all amber. After touching down; all indications were normal; i.e. spoilers and thrust reverser's. Exiting the runway; we received an ENG 1 and ENG 2 NO DISPATCH message as well as a CRG FIRE PROT FAULT message. We started the APU on the taxi in but left both engines running all the way to the gate. We shut down both engines and the APU Generator successfully powered AC BUS 1 and its associated components.
The reporter states that maintenance discovered a scorched electrical card in the power distribution assembly and replaced it allowing the aircraft to be returned to service.
EMB170 First Officer experiences fuel system and pressurization anomalies at FL340. The crew elects to descend and divert when the ECS Synoptic page indicates that both packs are off although the EICAS cabin pressure indicates normal. At lower altitude the Pack's appear to recover on their own but electrical anomalies begin to appear. After landing a CARGO FIRE PROT FAULT message is displayed.