B767 RELIEF PLT VACATING THE CAPT SEAT UPON CREW CHANGE HIT HIS HEAD ON THE OVERHEAD PANEL TURNING THE STAND BY PWR SWITCH OFF.

Narrative

I WAS RELIEF PLT IN CAPT'S SEAT. WE HAD NOTIFIED THE CAPT THAT HIS BREAK WAS OVER A FEW MINS EARLIER. MEANWHILE; WE CHKED IN WITH GANDER. WHEN THEY HAD RADAR CONTACT; WE WERE TOLD TO CLB FROM FL350 TO FL360. WE INITIATED THE CLB AND THE CAPT CALLED THAT HE WAS READY TO COME IN. WHEN I STOOD UP TO LET HIM IN; MY HEAD BUMPED THE OVERHEAD PANEL. WE DIDN'T SEE ANY SWITCHES MOVED AND I WENT BACK TO OPEN THE DOOR. AS I OPENED THE DOOR; THE FO SHOUTED THE AUTOPLT HAD JUST DROPPED OFF LINE AND ALL THE CAPT'S INSTS WERE OFF. THE CAPT QUICKLY GOT IN HIS SEAT; WHILE THE FO LEVELED THE ACFT AT FL360. WE'D LOST THE L RADIOS; L FLT INSTS; TXP; L EEC; L PACK; 1 UTILITY BUS; AND COULD FEEL A GRADUAL INCREASE IN CABIN ALT; BUT THE CABIN ALT GAUGE WAS NOW INOP AT ZERO. THE FO MENTIONED TO THE CAPT THAT I'D HIT MY HEAD ON THE PANEL; THE CAPT WAS SWITCHING OVER TO THE OTHER RADIO TO INITIATE A DSCNT; AND I RECHKED THE OVERHEAD PANEL AND SAW THAT THE STANDBY PWR SWITCH WAS OFF. I TURNED IT BACK TO 'AUTO' AND THE CABIN PRESSURE CTL CAME BACK AND WAS AT 7000-8000 FT. WE WERE ABLE TO CLR UP ALL THE OTHER PROBS EXCEPT THE L ENG EEC. WE RAN THE IRREGULAR PROC FOR THAT; CONTACTED MAINT AND DISPATCH; AND EXPLAINED WHAT HAPPENED TO THE FLT ATTENDANTS. WE CONTINUED WITH NO FURTHER PROBS.