Narrative:

At FL250 en route from ZZZ area to ZZZ1; began to encounter light turbulence in light cloud. Without warning; a lightning bolt struck the aircraft and concurrently encountered severe turbulence. All EFIS screens went blank; static in cockpit so loud that intercom to backseater unusable; generator fell off line; landing gear unsafe lights on; VHF comrdo's overcome by static; autoplt unusable. Engine operated normally. Standby EFIS came back on line after a short time; but main primary flight display was giving only partial information; being attitude; heading; but no air data. We were unsure if navigation instrumentation was operating correctly. ATC called and stated our altitude had deviated significantly; and the standby EFIS indicated we were several hundred ft off assigned altitude. ATC requested we call a phone number. It appeared that we had hit a severe turbulent updraft. We informed ATC we were struck by lightning and requested descent. Came out of cloud into clear conditions. The electronic instrumentation began to come back on line after reboot. However; the generator would not stay on line and the landing gear unsafe light remained illuminated. We decided to divert to ZZZ2. Gear came down normally and landing uneventful. Upon inspection of aircraft; evidence of lightning strike was evident. Removed gen control unit and it looked like someone had taken a torch to it. Aircraft was repaired over a 2-DAY period and returned to svcability.

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Original NASA ASRS Text

Title: PLT AND PAX ABOARD HIGH PERFORMANCE TURBINE HOMEBUILT EXPERIENCE LIGHTNING STRIKE THAT DISABLES MUCH OF THE NAVIGATION EQUIPMENT DUE TO DESTRUCTION OF THE GENERATOR CONTROL UNIT.

Narrative: AT FL250 ENRTE FROM ZZZ AREA TO ZZZ1; BEGAN TO ENCOUNTER LIGHT TURB IN LIGHT CLOUD. WITHOUT WARNING; A LIGHTNING BOLT STRUCK THE ACFT AND CONCURRENTLY ENCOUNTERED SEVERE TURB. ALL EFIS SCREENS WENT BLANK; STATIC IN COCKPIT SO LOUD THAT INTERCOM TO BACKSEATER UNUSABLE; GENERATOR FELL OFF LINE; LNDG GEAR UNSAFE LIGHTS ON; VHF COMRDO'S OVERCOME BY STATIC; AUTOPLT UNUSABLE. ENG OPERATED NORMALLY. STANDBY EFIS CAME BACK ON LINE AFTER A SHORT TIME; BUT MAIN PRIMARY FLT DISPLAY WAS GIVING ONLY PARTIAL INFO; BEING ATTITUDE; HDG; BUT NO AIR DATA. WE WERE UNSURE IF NAV INSTRUMENTATION WAS OPERATING CORRECTLY. ATC CALLED AND STATED OUR ALT HAD DEVIATED SIGNIFICANTLY; AND THE STANDBY EFIS INDICATED WE WERE SEVERAL HUNDRED FT OFF ASSIGNED ALT. ATC REQUESTED WE CALL A PHONE NUMBER. IT APPEARED THAT WE HAD HIT A SEVERE TURBULENT UPDRAFT. WE INFORMED ATC WE WERE STRUCK BY LIGHTNING AND REQUESTED DSCNT. CAME OUT OF CLOUD INTO CLR CONDITIONS. THE ELECTRONIC INSTRUMENTATION BEGAN TO COME BACK ON LINE AFTER REBOOT. HOWEVER; THE GENERATOR WOULD NOT STAY ON LINE AND THE LNDG GEAR UNSAFE LIGHT REMAINED ILLUMINATED. WE DECIDED TO DIVERT TO ZZZ2. GEAR CAME DOWN NORMALLY AND LNDG UNEVENTFUL. UPON INSPECTION OF ACFT; EVIDENCE OF LIGHTNING STRIKE WAS EVIDENT. REMOVED GEN CTL UNIT AND IT LOOKED LIKE SOMEONE HAD TAKEN A TORCH TO IT. ACFT WAS REPAIRED OVER A 2-DAY PERIOD AND RETURNED TO SVCABILITY.

Data retrieved from NASA's ASRS site as of May 2009 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.