Narrative:

We were cruising at FL430 in VMC conditions. We suddenly lost all electrical power and cabin pressurization. The memory item is to don oxygen masks and perform an immediate descent. We began accomplishing both of these. With a loss of electrical power; the phenom starts dutch rolling right away. As the pilot flying; my attention was primarily focused on getting the aircraft down and controlling the roll. I had been unable to turn on my mask mic right away; and assumed the non-flying pilot was communicating with ATC and squawking 7700. It turns out that he was unable to speak to ATC. I think we probably descended to about 25;000 feet before either of us talked to ATC. Once I made contact with center; we requested priority handling and received excellent assistance.once I had the aircraft under control and we were at a lower altitude; the sic informed me that he could not communicate. At that point I gave him the flight controls while I got my mask mic working and I contacted ATC. The loss of electrical power prevented the non-flying pilot to communicate outside the aircraft. My focus was on controlling the dutch roll while descending at up to 8000 FPM. As my mask mic was not yet working; I was unaware that the sic had not spoken to ATC.ATC responded right away; gave us clearance to 10;000 feet and assisted us getting on the ground.we (company) should probably practice this event; or at least discuss it during recurrent. It was very confusing; and we were quite task saturated.

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Original NASA ASRS Text

Title: EMB-505 flight crew reported total loss of electrical power caused multiple systems failures resulting in a diversion and landing.

Narrative: We were cruising at FL430 in VMC conditions. We suddenly lost all electrical power and cabin pressurization. The memory item is to don oxygen masks and perform an immediate descent. We began accomplishing both of these. With a loss of electrical power; the Phenom starts Dutch Rolling right away. As the Pilot Flying; my attention was primarily focused on getting the aircraft down and controlling the roll. I had been unable to turn on my mask mic right away; and assumed the Non-Flying Pilot was communicating with ATC and squawking 7700. It turns out that he was unable to speak to ATC. I think we probably descended to about 25;000 feet before either of us talked to ATC. Once I made contact with Center; we requested priority handling and received excellent assistance.Once I had the aircraft under control and we were at a lower altitude; the SIC informed me that he could not communicate. At that point I gave him the flight controls while I got my mask mic working and I contacted ATC. The loss of electrical power prevented the non-flying pilot to communicate outside the aircraft. My focus was on controlling the dutch roll while descending at up to 8000 FPM. As my mask mic was not yet working; I was unaware that the SIC had not spoken to ATC.ATC responded right away; gave us clearance to 10;000 feet and assisted us getting on the ground.We (Company) should probably practice this event; or at least discuss it during recurrent. It was very confusing; and we were quite task saturated.

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.