Boeing has shown airlines a blueprint for the world's longest-range passenger jet, adding spice to a long-awaited revamp of its 777 wide-body jet.
Boeing last week launched a race against Airbus for sales of the newest long-haul jets by announcing it had begun selling an upgraded aircraft family code-named 777X.
First seen in the 1990s, the 777 cornered the market for large twin-engine aircraft able to fly routes previously only possible with four engines, earning it the nickname "mini-jumbo."
Analysts say the 777 is Boeing's most profitable plane, thanks largely to the 777-300ER, a 365-seat version that began operations in 2004.
Most of the industry's attention is now focused on a future 400-seat version known as the 777-9X, which is Boeing's response to a growing challenge from the largest version of Europe's newest aircraft, the Airbus A350-1000.
But talks between Boeing and potential buyers have also generated interest in a 777-8X that would be a successor to the 777-200LR, the industry's current distance champion, with a range of more than 9300 nautical miles (17,200 km), people briefed on the talks said.
The 777-8X, boasting a range of 9500 nautical miles (17,600 km), would be designed for some of the world's longest trips such as from the Middle East to South America. It could potentially make flights from Australia's east coast to London non-stop.
"They are offering an ultra-long range aircraft in the 777-8X," said an industry source briefed on the plans. "It'll be the longest range aircraft in the business."
Boeing declined to comment on specifics, but spokeswoman Karen Crabtree said the company is working with customers to fine tune the details.
Experts say ultra-long range planes deliver mixed benefits to airlines and so far the market for them remains a niche, overshadowed by the juggernauts designed for trunk routes.
That is because when modern aircraft fly the longest 15-hour flights, the first few hours are spent mostly burning the fuel needed to carry even more fuel for the rest of the flight.
These aircraft "carry more fuel to carry more fuel," said consultant Richard Aboulafia of Virginia-based Teal Group.
"They need a very big wing with lots of (fuel storage) capacity, which means lots of structure and weight."
Fuel is not the only source of extra weight. The long journey times also mean loading extra meals and a reserve crew, so that the fuel burned per hour - a measure of efficiency - can end up greater than if the plane simply stopped en route.
Airlines must balance this against any extra revenue they can charge for a direct flight and the ability to eliminate the fuel wasted in climbing and descending twice, as well as en-route landing fees and other costs linked to a stopover.
Proof that ultra-long haul is not for everyone is contained in a quick comparison of sales for comparable existing models.
Boeing has sold 59 of its 777-200LR endurance jet, which entered service in 2007, compared with 687 of the shorter-range but highly popular 777-300ER.
Air India has announced plans to sell five 777-200LR's and one industry source said some or all could end up being acquired by the government for VIP transport. Air India declined comment.
Before the 777-200LR, the industry's previous long-distance record-holder, the Airbus A340-500, was capable of flying 9000 nautical miles (13,480km) on polar routes yet notched up fewer than 40 sales.
Production was halted in 2011, driven also by a wider slowdown in sales for all but the largest four-engine aircraft.
Reflecting thinner demand for super-long haul, the 777-8X is expected to take a backseat to the 777-9X, which is seen as the main weapon in an all-out defence of Boeing's mini-jumbo franchise. The main model is slated to enter service at the end of the decade.
Nonetheless, recent public presentations suggest Boeing is confident the significantly enlarged wing and more powerful engines designed for the main 777-9X model will give airlines the flexibility to use the 777-8X spin-off more efficiently.
Randy Tinseth, vice president of Boeing marketing, told financiers in January the 777X would have "significantly lower operating cost" and greater payload and range ability. Airbus says its 350-seater is the right size and costs less to run.
As both sides trot out competing claims, the 777 vs A350 contest is likely to spark a fierce debate on technology - just as the industry digests the lessons of recent technical troubles on the 787 Dreamliner and, before that, the A380 superjumbo.
Boeing is expected to argue that its decision to keep the 777's metal fuselage and focus on new carbon-fiber wings will marry increased performance with a proven record of reliability.
Airbus argues its A350-1000, the largest variant of its A350 family, will be cheaper to run because the whole plane, not just the wings, will be mainly built of lightweight carbon fibre.
Ironically, the two rivals are taking roughly opposite positions at the smaller end of the market for wide-bodied jets, where Boeing is pushing a possible all-composite stretched version of its 787 Dreamliner against the traditional A330, an older plane marketed on reliability and availability.
Both the 777 and A330 are important cash cows, helping to produce the funds needed to pay for ground-breaking developments such as the 787 and A350.
MIDDLE EAST ORDERS
Meanwhile, Gulf airline giants Emirates and Qatar Airways are warning that Boeing must avoid the mistakes of the 787 Dreamliner with the new 777s, which cost customers millions of dollars when its batteries failed.
These fast-growing Gulf carriers are expected to be among the first and possibly biggest customers for Boeing's latest offering.
"For sure they have changed, I hope they have," Emirates' President Tim Clark said, when asked whether the Dreamliner crisis has changed Boeing's approach and thinking.
"Boeing came out of the ashes of the Sonic Cruiser years ago and came up with the Dreamliner, which was a leap of faith by any stretch. They were just beginning to stabilise when things went wrong again," said Clark.
Emirates is not a customer of the Dreamliner but is the largest 777 operator with up to 175 jets that will need replacing soon.
Qatar Airways, which grounded all its five Dreamliner aircraft, would receive compensation from Boeing, its chief executive Akbar al Baker said.
"Everyone takes risks but Boeing took a very big risk because they went from ground zero to 100 in one leap instead of going in stages," Qatar Airways' outspoken chief Baker said on board its first 787 flight from Dubai to Doha last week, after the battery fix was installed.
Apart from Qatar Airways, fast-growing Gulf airline Etihad Airways has 41 Dreamliners on order.
"We put together a permanent and comprehensive fix for the issue and we are confident of the 787 safety," Boeing's Middle East President Jeff Johnson said when asked about assurances to its Gulf customers.
US regulators formally lifted flight restrictions on the 787 last month and allowed the redesigned lithium-ion battery system to be installed in airlines.
Ethiopian Airlines became the first carrier last month to resume flying the revamped Dreamliner followed by All Nippon Airways and Qatar Airways.
Eight airlines currently own Dreamliners including United Airlines, ANA, JAL, Air India Ltd, LATAM Airlines Group and LOT Polish Airlines.
Under questioning from aviation authorities last month, Boeing said it would more rigorously challenge its test assumptions in the future, and that its analysis of the problem could change as more facts become known.
"Things will not be so easy for them in the US now. Boeing has to learn from that too as a lot of the 787 was self-certified," said Emirates' Clark.
Clark said the plane maker has a lot to learn from the Dreamliner crisis.
"Perhaps Boeing was not quite ready for it all (the 787). But the crisis helped them learn a lot about design, metallurgy."
The US company may also rethink its overseas manufacturing.
"They placed their faith in supplies from overseas manufacturers and expected them to be as good as they wanted. That is something they will be less inclined to do now," said Clark.
The industry is learning from the Dreamliner experience and is also pushing harder on areas such as aircraft propulsion, engine technology, batteries and others.
"Like in every new product there will be continuous improvement," said Baker.
"Boeing has a permanent solution now but as new processes are developed, so will new batteries. It may not be the lithium-ion batteries later, it may be something else. I'm sure Boeing will look for improvements in the batteries."
The halt to Dreamliner flights has cost Boeing an estimated $600 million and forced it to halt deliveries.
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