Narrative:

Upon taking off; I noticed that we had an avionics; electrical; and avionics vent lights on the cwp. At that time communication between the captain; tower and departure were unable to take place due to the nature of the equipment malfunctions. I also noticed that the captains EFIS screens were blank; his instruments were not functional and the mfd was also not functioning. I informed ATC of the problems and that we would be returning. My ehsi froze and stopped accurately reporting the heading so I briefly resorted to using the magnetic compass to turn to an assigned heading. The autopilot disconnected in the midst of everything else that was happening simultaneously. I assumed both pilot flying and pilot monitoring duties as the captain ran the checklist and tried to communicate with his radios. We lost our transponder along with everything else and it was when ATC informed us of the transponder failure that I realized that we had climbed through our assigned altitude. We quickly corrected the altitude and returned; on short final we received the hydraulic look down cwp warning and realized that the accumulator read 0 psi. The captain performed the memory items and we continued to land.it is unknown why the electrical system and hydraulic system malfunctioned. I initially climbed through the assigned altitude because of the high workload that I instantly found myself dealing with.

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Original NASA ASRS Text

Title: SF340 flight crew experienced an altitude deviation while they troubleshot multiple electrical failures on departure followed by a HYD CWP Master Caution as they returned to their departure airport.

Narrative: Upon taking off; I noticed that we had an avionics; electrical; and avionics vent lights on the CWP. At that time communication between the Captain; Tower and Departure were unable to take place due to the nature of the equipment malfunctions. I also noticed that the Captains EFIS screens were blank; his instruments were not functional and the MFD was also not functioning. I informed ATC of the problems and that we would be returning. My EHSI froze and stopped accurately reporting the heading so I briefly resorted to using the magnetic compass to turn to an assigned heading. The autopilot disconnected in the midst of everything else that was happening simultaneously. I assumed both pilot flying and pilot monitoring duties as the Captain ran the checklist and tried to communicate with his radios. We lost our transponder along with everything else and it was when ATC informed us of the transponder failure that I realized that we had climbed through our assigned altitude. We quickly corrected the altitude and returned; on short final we received the HYD look down CWP warning and realized that the accumulator read 0 PSI. The Captain performed the memory items and we continued to land.It is unknown why the electrical system and hydraulic system malfunctioned. I initially climbed through the assigned altitude because of the high workload that I instantly found myself dealing with.

Data retrieved from NASA's ASRS site as of April 2012 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.