Originally Posted by
pixitha
asked this on another thread but it was misplaced...
Not knowing the technical details myself, why can't UA (or any airline) replace the 747 with a 777? (using existing aircraft, not 77X or anything in the pipeline)
They can, on most routes, if they're willing to accept the reduced capacity.
A few routes you still need four engines, but UA doesn't fly any of those. (SYD-SCL or SYD-JNB though, for instance.)