Narrative:

Cruising in clouds at FL340 with thunderstorms approximately 5 miles south produced heavy amounts of st elmo's fire. We lost some flight instruments (a/south; aoa); automation (FD; autoplt; autothrottle) and aircraft systems (rudder rotation; elevator feel; flap asymmetry; etc) and smelled electrical smoke. We declared emergency and started deviation towards ZZZ. After approximately 5 mins of flying standby -- all systems returned slowly. The emergency was cancelled and flight completed.

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Original NASA ASRS Text

Title: B757 FLT CREW ENCOUNTERS WX; AUTO FLT SYSTEMS FAIL; FUMES IN COCKPIT. DECLARES AN EMER.

Narrative: CRUISING IN CLOUDS AT FL340 WITH TSTMS APPROX 5 MILES S PRODUCED HVY AMOUNTS OF ST ELMO'S FIRE. WE LOST SOME FLT INSTRUMENTS (A/S; AOA); AUTOMATION (FD; AUTOPLT; AUTOTHROTTLE) AND ACFT SYSTEMS (RUDDER ROTATION; ELEVATOR FEEL; FLAP ASYMMETRY; ETC) AND SMELLED ELECTRICAL SMOKE. WE DECLARED EMER AND STARTED DEVIATION TOWARDS ZZZ. AFTER APPROX 5 MINS OF FLYING STANDBY -- ALL SYSTEMS RETURNED SLOWLY. THE EMER WAS CANCELLED AND FLT COMPLETED.

Data retrieved from NASA's ASRS site as of January 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.