Narrative:

Before departure; among other mechanical items; flight was delayed due to left CDU (control display unit) failure. Weak APU also flamed out/shutdown on its own at gate. They repaired CDU; left and right CDU swap tried during trouble-shooting. About 1 hour after departure in cruise flight; left CDU (the only one available if on standby electrical power) failed again. No inputs possible; no route/altitude/speed changes; ACARS functions or satcom control. No QRH procedure or instrument switching of cdus were available. Manual-allowed circuit breaker pulled to cool and reset; but no functions at all after reset. Through first officer's (first officer) CDU satcom; contacted dispatch; maintenance control; and chief pilot. Discussed options and learned of similar problem on the previous flight. Operations manual chart of required equipment missing 767-300s column; all other 757 and 767 models require 2 cdus. Decision was made that safest course of action was to return to ZZZ. Completed diversion planning. As a precaution; I [advised ATC]. To reduce weight below maximum landing weight since jet is unable to jettison fuel from wing tanks; and center fuel tank was empty; we descended to 10;000 feet; extended speedbrakes [and] lowered landing gear; which doubled fuel flow. Landing was made below maximum limit weight. Due to higher than normal speeds; and lengthy taxi; brake temp monitoring light was on at gate. Also one engine thrust reverser was inoperative. Abnormal landing distance was calculated. Completed recovery guide and maintenance write ups.

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Original NASA ASRS Text

Title: B767 Captain reported display unit issues after takeoff requiring a return to the departure airport.

Narrative: Before departure; among other mechanical items; flight was delayed due to left CDU (Control Display Unit) failure. Weak APU also flamed out/shutdown on its own at gate. They repaired CDU; left and right CDU swap tried during trouble-shooting. About 1 hour after departure in cruise flight; left CDU (the only one available if on standby electrical power) failed again. No inputs possible; no route/altitude/speed changes; ACARS functions or SATCOM control. No QRH procedure or instrument switching of CDUs were available. Manual-allowed circuit breaker pulled to cool and reset; but no functions at all after reset. Through F/O's (First Officer) CDU SATCOM; contacted Dispatch; Maintenance Control; and Chief Pilot. Discussed options and learned of similar problem on the previous flight. Operations Manual chart of required equipment missing 767-300s column; all other 757 and 767 models require 2 CDUs. Decision was made that safest course of action was to return to ZZZ. Completed diversion planning. As a precaution; I [advised ATC]. To reduce weight below maximum landing weight since jet is unable to jettison fuel from wing tanks; and center fuel tank was empty; we descended to 10;000 feet; extended speedbrakes [and] lowered landing gear; which doubled fuel flow. Landing was made below maximum limit weight. Due to higher than normal speeds; and lengthy taxi; brake temp monitoring light was on at gate. Also one engine thrust reverser was inoperative. Abnormal landing distance was calculated. Completed recovery guide and maintenance write ups.

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.