I liked Beagle's comment....
It can but should it?
With over 10K on type I feel it's time to make a comment.
This is a very interesting thread and believe me some of the takeaways will be written into SOPs.
London to a brick the skipper was young...at least by BA standards...let me guess...early 40's. Now why do I say that?
Quite simply because that is what I would have done 10 years ago.
Would I do it today? In short NO. The a/c can do it but should it. Simple answer is NO.
This case is a classic text book example of limits.
Years ago I was taught to understand where you had toolboxes, spares and some engineering talent. If you had them in proximity then return. If not then push the envelope.
In this case general knowledge and a few questions would have been in order. LAX...what have we got...CX,QF and BA with the Rollers...spare engine...spare bits??...quick call. What else have we got? Seattle, Vancouver, Chicago, Toronto, JFK...no 400's with Rollers. Logical answer is go back.
The 400's are getting on in years just as were the 1011's when I started. So...you have the book which says one thing, you have the commercial pressure and above all you have your own rear end.
Ten years ago the tea and biscuit factor would have had an influence. Now it does not.
In short, the Old Girl can do it but common sense says don't push her to prove she can.
Beagle is right on the money. The operation was safe and theoretically justified but was it philosophically correct?
Would I have done it. NO esp[ecially heading for HKG. But then I can sit through a tea and bikkies and afford to get fired...unlike most of my brethren.