Embraer 550 flight crew reported an electrical warning message during cruise flight resulting in aircraft flight control and autoflight malfunctions. The crew diverted to an alternate airport and landed; requiring a tow to the FBO ramp.
Synopsis
Embraer 550 flight crew reported an electrical warning message during cruise flight resulting in aircraft flight control and autoflight malfunctions. The crew diverted to an alternate airport and landed; requiring a tow to the FBO ramp.
Narrative
While enroute at 45;000 feet; approximately 1.5 hours into our flight; the 'BATT 2 DISCHARGING' CAS message illuminated. The PF selected the electrical synoptic page while the PNF began to run the associated electronic checklist.The PF assumed radios and after a brief discussion about diverting; chose ZZZ as the best option due to its proximity of 17 minutes flight time; its long runways; and firefighting capabilities. The PF communicated with air traffic control; and coordinated a turn and decent. The PNF followed the checklist.The PNF began configuring the FMS performance data for the landing and conducting the normal checklist. The crew then noticed the battery voltage on battery two was in fact dropping from 27.2v at the time of failure to 26.8v. The crew elected to request priority handling; as well as attempt to start the APU; even though the Batt 2 discharge checklist notes the APU may not be available for start.Upon attempting the APU start; the right hand DU and lower DU simultaneously failed; as well as the A/P and A/T. The aircraft also began an un-commanded roll to the right which the PF was able to stop it and return the aircraft to level flight. The crew then received multiple additional CAS messages.The PF & PNF prioritized each CAS message and ran the most appropriate checklist as presented to the crew. The most notable was 'STALL PROT ANTICIPATE' and 'BRAKE LH(RH) FAULT'. The associated checklist for each of these were accomplished; resulting in approach speeds being manually selected and entered for the approach by the PNF (~148 kts). The PF then asked ATC to have fire and rescue standing by. Upon turning final; the SFIS failed and went dark. The '>DC EMER BUS 2 OFF' CAS and 'FLIGHT CONTROL NO DISPATCH' also displayed during final approach and landing. Some of the relevant systems became inoperative including NAV/COM 2 necessitating a switch to COM 1 for further communication with ARFF and ATC.The brake fault checklist indicates that inboard or outboard brakes are available and after touchdown apply symmetric braking until reaching 20 kts using rudder and steering to maintain centerline. It also presented with a note that states: 'due to brake symmetry; the airplane may steer away sharply from the centerline.'With this knowledge; the PF brought the airplane to a stop under control in approximately 6000 feet; stopping just short of Taxiway T6 on Runway 36R causing the outboard brakes to rapidly heat. Once the aircraft came to a stop; the 'BRAKE OVERHEAT' CAS message displayed; prompting the crew to set the brakes and request wheel chocks be placed on the nose gear so that we could release the parking brake for cooling in accordance with the checklist.Without the ability to start the APU; the crew elected to power down the aircraft completely; as to not have emergency responders chock the aircraft with engines running.The crew then coordinated with Airport Rescue Firefighting Command; and Air Traffic Control to power down the aircraft and confirm there was not smoke or anything visibly wrong from the outside. The crew ran the appropriate shut down checklist and deplaned passengers out the main cabin door. The aircraft was then towed without incident to the FBO.
Second reporter narrative
While en-route at 45;000 feet; approximately 1.5 hours into our flight; the 'BATT 2 DISCHARGING' CAS message illuminated. The PF selected the electrical synoptic page while the PNF began to run the associated electronic checklist. The PF assumed radios and after a brief discussion about diverting; chose ZZZ as the best option due to its proximity of 17 minutes flight time; its long runways; and firefighting capabilities. The PF communicated with air traffic control; and coordinated a turn and decent. The PNF followed the checklist. The PNF began configuring the FMS performance data for the landing and conducting the normal checklist. The crew then noticed the battery voltage on battery two was in fact dropping from 27.2v at the time of failure to 26.8v. The crew elected to request priority handling; as well as attempt to start the APU; even though the Batt 2 discharge checklist notes the APU may not be available for start. Upon attempting the APU start; the right hand DU and lower DU simultaneously failed; as well as the A/P and A/T. The aircraft also began an un-commanded roll to the right which the PF was able to stop it and return the aircraft to level flight. The crew then received multiple additional CAS messages. The PF & PNF prioritized each CAS message and ran the most appropriate checklist as presented to the crew. The most notable was 'STALL PROT ANTICIPATE' and 'BRAKE LH(RH) FAULT'. The associated checklist for each of these were accomplished; resulting in approach speeds being manually selected and entered for the approach by the PNF (~148 kts). The PF then asked ATC to have fire and rescue standing by. Upon turning final; the SFIS failed and went dark. The '>DC BUS 2 OFF' CAS also displayed during final approach and landing and some of the relevant systems became inoperative including NAV/COM 2 necessitating a COM 1 for further communication with ARFF and ATC.The brake fault checklist indicates that inboard or outboard brakes are available and after touchdown apply symmetric braking until reaching 20 kts using rudder and steering to maintain centerline. It also presented with a note that states: 'due to brake symmetry; the airplane may steer away sharply from the centerline.'With this knowledge; the PF brought the airplane to a stop under control in approximately 6000 feet; stopping just short of Taxiway 1A on Runway XXR causing the outboard brakes to rapidly heat. Once the aircraft came to a stop; the 'BRAKE OVERHEAT' CAS message displayed; prompting the crew to set the brakes and request wheel chocks be placed on the nose gear so that we could release the parking brake for cooling in accordance with the checklist. Without the ability to start the APU; the crew elected to power down the aircraft completely; as to not have emergency responders chalk the aircraft with engines running. The crew then coordinated with Airport Rescue Firefighting Command; and Air Traffic Control to power down the aircraft and confirm there was not smoke or anything visibly wrong from the outside. The crew ran the appropriate shut down checklist and deplaned passengers out the main cabin door. The aircraft was then towed without incident to the FBO.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.