Narrative:

After reaching cruise from ZZZ-ZZZ1 the captain and I heard a clicking noise repeatedly for 10 or 15 seconds. We both found it odd and commented on the noise. Shortly after the noise the captain's eadi (electronic attitude director indicator) flickered and blanked out. The captain transferred control of the airplane to me and decided to call dispatch and maintenance. While on the phone with dispatch the captains eadi returned to operation; but was shortly followed by his ehsi (electronic horizontal situation indicator) flickering and going black. The ehsi remained inop the remainder of the flight. Shortly after this switch in screens failing the captain asked both first officers if we smell anything. I immediately smelled fumes and we dawned our oxygen masks. The captain gave dispatch a quick update and hung up the sat call. We informed center that we would like to return to ZZZ. They replied with a right hand turn to 270 and then direct. We then received an ACARS (aircraft communications and reporting system) from dispatch stating that ZZZ2 was closer if we wanted it. We all agreed that ZZZ2 was a better option and asked center for a course to ZZZ2. During the descent we realized that we would be doing an overweight landing; but that we could also jettison 12.5 thousand pounds of fuel to lessen the landing weight. We determined at this point that we needed to request priority handling and advised center. After receiving clearance we performed the jettison procedure between fl 320 and fl 240 approximately. The smoke fire fumes QRH (quick reference handbook) procedure was accomplished to the extent possible throughout the diversion by the pilot observing. The captain set me up for the ILS in ZZZ2 and gave me a briefing on the approach. We kept the speed around 320 knots until a ten mile final and then began to slow. We were stable at a flaps 30 approach speed of 163 knots by 1200 ft. An overweight landing was made at 357.0 thousand pounds. The touchdown was smooth. Autobrakes three were applied along with full reverse thrust to 80 kts. We decided to exit the runway where fire and rescue was waiting. They performed an inspection of the airplane and found no fire or imminent danger. We then taxiied to parking with one fire truck following for our hot brakes. The brakes reached 6 on the btms (brake temperature monitoring system). After arriving at parking we were chocked after warning the ground crew of the hot brakes. The brake was released after chocked and the fire team told they were safe to depart. Dispatch did a stand up job of coordinating with us during this emergency. Their promptness was unparalleled.

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Original NASA ASRS Text

Title: B767-300ER flight crew encountered flight instrument failure inflight.

Narrative: After reaching cruise from ZZZ-ZZZ1 the Captain and I heard a clicking noise repeatedly for 10 or 15 seconds. We both found it odd and commented on the noise. Shortly after the noise the Captain's EADI (Electronic Attitude Director Indicator) flickered and blanked out. The Captain transferred control of the airplane to me and decided to call Dispatch and Maintenance. While on the phone with Dispatch the Captains EADI returned to operation; but was shortly followed by his EHSI (Electronic Horizontal Situation Indicator) flickering and going black. The EHSI remained inop the remainder of the flight. Shortly after this switch in screens failing the Captain asked both First Officers if we smell anything. I immediately smelled fumes and we dawned our oxygen masks. The Captain gave Dispatch a quick update and hung up the sat call. We informed Center that we would like to return to ZZZ. They replied with a right hand turn to 270 and then direct. We then received an ACARS (Aircraft Communications And Reporting System) from dispatch stating that ZZZ2 was closer if we wanted it. We all agreed that ZZZ2 was a better option and asked Center for a course to ZZZ2. During the descent we realized that we would be doing an overweight landing; but that we could also jettison 12.5 thousand pounds of fuel to lessen the landing weight. We determined at this point that we needed to request priority handling and advised Center. After receiving clearance we performed the jettison procedure between FL 320 and FL 240 approximately. The smoke fire fumes QRH (Quick Reference Handbook) procedure was accomplished to the extent possible throughout the diversion by the pilot observing. The Captain set me up for the ILS in ZZZ2 and gave me a briefing on the approach. We kept the speed around 320 knots until a ten mile final and then began to slow. We were stable at a flaps 30 approach speed of 163 knots by 1200 ft. An overweight landing was made at 357.0 thousand pounds. The touchdown was smooth. Autobrakes three were applied along with full reverse thrust to 80 kts. We decided to exit the runway where fire and rescue was waiting. They performed an inspection of the airplane and found no fire or imminent danger. We then taxiied to parking with one fire truck following for our hot brakes. The brakes reached 6 on the BTMS (Brake Temperature Monitoring System). After arriving at parking we were chocked after warning the ground crew of the hot brakes. The brake was released after chocked and the fire team told they were safe to depart. Dispatch did a stand up job of coordinating with us during this emergency. Their promptness was unparalleled.

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.