An air carrier widebody transport suffered multiple instrument failures.

Attributes
ACN	260083
Time
Date	199312
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : sfo
State Reference	CA
Altitude	msl bound lower : 32000 msl bound upper : 32000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zoa
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 3 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	climbout : intermediate altitude cruise other
Route In Use	enroute : other oceanic enroute : pacific
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 7900 flight time type : 500
ASRS Report	260083
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	none taken : unable other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

After takeoff from sfo, lost #1 automatic throttle followed by #1 central air data computer. Lost all instruments corresponding to #1 air data computer. First officer flying. First officer's instruments ok. Captain selected input from other air data computer for his instruments. First officer assigned to fly while captain and flight engineer worked on problem. #1 ONS out, would not come out of dr. Subsequently lost #2 mach trim in addition to #1 being out and #1 mach feel also out. Decision made to return to sfo. Notified center and began return to sfo. Reviewed fuel dump procedures/time, and when given permission by center, began fuel dump. Notified company who then called us back requesting we go to lax for parts. Stopped fuel dump, assessed fuel remaining and went to lax. Landed without incident. Having flown medium large transport's for many yrs, this was the first time I was involved in an abnormal procedure with a 3 person crew. I strongly feel the 3 person crew works extremely well. With 1 person assigned to fly while the other 2 crew members worked on the problem, there was never any question or diversion. The plane was always under control. The captain did an excellent job of assessing the situation and supervising. Also, having 2 people review the checklist provides for greater checks and balances, without diverting attention from the PF.

Original NASA ASRS Text

Title: AN ACR WDB SUFFERED MULTIPLE INST FAILURES.

Narrative: AFTER TKOF FROM SFO, LOST #1 AUTO THROTTLE FOLLOWED BY #1 CENTRAL AIR DATA COMPUTER. LOST ALL INSTS CORRESPONDING TO #1 AIR DATA COMPUTER. FO FLYING. FO'S INSTS OK. CAPT SELECTED INPUT FROM OTHER AIR DATA COMPUTER FOR HIS INSTS. FO ASSIGNED TO FLY WHILE CAPT AND FE WORKED ON PROB. #1 ONS OUT, WOULD NOT COME OUT OF DR. SUBSEQUENTLY LOST #2 MACH TRIM IN ADDITION TO #1 BEING OUT AND #1 MACH FEEL ALSO OUT. DECISION MADE TO RETURN TO SFO. NOTIFIED CTR AND BEGAN RETURN TO SFO. REVIEWED FUEL DUMP PROCS/TIME, AND WHEN GIVEN PERMISSION BY CTR, BEGAN FUEL DUMP. NOTIFIED COMPANY WHO THEN CALLED US BACK REQUESTING WE GO TO LAX FOR PARTS. STOPPED FUEL DUMP, ASSESSED FUEL REMAINING AND WENT TO LAX. LANDED WITHOUT INCIDENT. HAVING FLOWN MLG'S FOR MANY YRS, THIS WAS THE FIRST TIME I WAS INVOLVED IN AN ABNORMAL PROC WITH A 3 PERSON CREW. I STRONGLY FEEL THE 3 PERSON CREW WORKS EXTREMELY WELL. WITH 1 PERSON ASSIGNED TO FLY WHILE THE OTHER 2 CREW MEMBERS WORKED ON THE PROB, THERE WAS NEVER ANY QUESTION OR DIVERSION. THE PLANE WAS ALWAYS UNDER CTL. THE CAPT DID AN EXCELLENT JOB OF ASSESSING THE SIT AND SUPERVISING. ALSO, HAVING 2 PEOPLE REVIEW THE CHKLIST PROVIDES FOR GREATER CHKS AND BALS, WITHOUT DIVERTING ATTN FROM THE PF.

Data retrieved from NASA's ASRS site as of July 2007 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.