There is a flaw with the argument about Boeing coming up with a whole new aircraft if the A3XX is a success, as I see it;
The A3XX is going ahead as we speak. It will have taken around 10 years from initial design to service entry. If Boeing decides to go ahead with the "787," Do you think airlines will sit around for 10 years and wait for it when they have a comparable aircraft that they could have much sooner?
Being second in the market can be very costly, as Boeing found out with the 737NG when United didn't wait for them and went with the A320.
If Boeing were thinking of a 787, what would the point of developing the 747X if it were to be superceeded by an all-new aircraft within a few years? The 747X will be cheaper
than the A3XX to develop, it will not be cheap
. As Avion pointed out, the 747X is based on a 30 year old platform. Some very significant changes will be required to make the aircraft compete with the A3XX.
Airlines would be very
reluctant to buy the B747X if there was even a hint that Boeing would bring out an all new aircraft in the future that would quickly make their expensive obsolete.
Financially for Boeing it would also not make sense, they would have to answer this very difficult question for their (probably angry) shareholders;
Why did you spend X million dollars developing the 747X, and then 5 years later spend X billion dollars developing the 787 to make the 747 and all the initial investment obsolete?
As for the above comments on the A340, I'm loathed to reply, but here it is anyway;
-The B777 is
wider than the A340, meaning 9 or 10 abreast seating insted of 8 abreast in the A340 - What an advantage!
-The B777 may
be cheaper to operate. Actual figures are not known until flight testing is complete, the airframe/engine combination may be better (like the 717) or worse (like the MD-11) than predicted. Even if the A340 does cost very slightly more to operate, so what? Airlines don't choose aircraft on operating costs alone or B757-300 sales would be past the 1000 mark!
- The A340-600 is not liked by Northwest F/As, an airline that has not ordered the A340 because they think they are experts in evacuation safety (they are not)
The A340 is slower than the B777 and can't fly as far, those are 2 actual disadvantages you didn't mention!
"the Europeans will order it, and thee 777X project will whip Airbus in the hiney again"
Egyptair, Emirates, Singapore Airlines, Lufthansa, Swissair, Virgin, Aerolineas Argentinas, Air Canada, China Eastern, ILFC - all of course European