distance is longer, winds are stronger
It would be nice to fly Great Circles but politics and geography may say otherwise. Lots of nice people have to say yes and to date the yesfulness has not being encouraging when it comes to making the sky free.
Will the B777 fly on route L888 or what? Let's say it does to the extent that the authorities permit YSSY DCT BIDRU DCT KCA DCT EGLL the route cannot be shorter than 9200nm.
Apart from the legal niceties, what quid pro quo would be expected by the likes of Indonesia, China and the CIS to permit this? And what sort of lobbying would go on behind the scenes by, ahem, companies that have vested interests in the non-success of the venture?
Suppose that on the grounds of driftdown for one thing the B777 (initially at least) is restricted to flying south of the Himalayas. The route on airways is 4122nm to overfly VTBD and 5628nm through Iran and Turkey. It would be a victory for the less than pro-US, pro-Boeing camp (if such a thing exists in this world of universal bonhomie and brotherly goodwill).
Somewhere in between then, 9450nm or 10880 statute miles? Coincidentally about the same distance as YSSY DCT RJAA DCT EGLL.
M0.83 against a 35kt HW all the way is 21hr 30mins. M0.84 against a 20kt HW all the way is 20hr 30mins. Knowing something of the winds I'd favour the upper figure of the two.
Head Winds never balance out Tail Winds. It's the first law of flying and despite the fact that farmers have produced a butter mountain and a wine lake it can only get worse. Some looney in the Common Market is handing out subsidies to start up wind farms!