By Tom Symonds
Transport Correspondent, BBC News, Everett, Washington State
It takes thousands of people to design and build a new airliner.
Crowds were allowed up close to the new plane
And they came - also in their thousands - to the ceremony that launched Boeing's 787 Dreamliner.
It was a flashy show, staged in the vast factory where the new plane is being built. At its climax the giant hangar doors opened and there, in the sunlight, was their plane.
As Boeing's staff surrounded the Dreamliner, their hands went up to touch its skin. After all, that is what is different about this airliner: instead of metal, its outside is an advanced carbon fibre and plastic mix.
It allows Boeing to design new aerodynamic shapes to improve the plane's efficiency. The wings, for instance, have a twist at their tips.
And carbon fibre is lighter than aluminium too - so less fuel is needed.
As a result, airlines are flooding Boeing with orders for 787s: 677 at last count. And many of these customers are talking about the 787's green credentials.
From Sonic Cruiser to Dreamliner
There's no doubt that this plane is Boeing's great hope for the future.
Its development started in 2001, when Boeing bosses began trying to work out what the next big thing would be in the aviation industry.
They asked airlines if they wanted faster planes or more fuel-efficient ones. Of course, the airlines said both.
Boeing began designing a futuristic new airliner, the Sonic Cruiser, with a double tailplane, Concorde-style wings, and engines built into the fuselage. The Sonic Cruiser would fly close to the speed of sound.
Not quite as fast as Concorde, but very valuable for airlines who want to sell efficient business travel to time-starved executives.
But Sonic Cruiser never got off the ground: partly because of the slump in aviation following 9/11, which left airlines desperate for planes that were cheap to operate. Speed simply became less important.
Instead, the technology for the Sonic Cruiser was turned into a new aircraft, the 787 Dreamliner.
But amid the excitement the Dreamliner is generating, there are some advising a little caution.
While even environmentalists welcome the attempts to make planes greener, they don't think the 787 is going to do much to reduce the impact of aviation on climate change.
Boeing's future could depend on the Dreamliner's success
They believe that fuel-efficient planes are simply going to allow airlines to carry the same number of passengers, more cheaply. And that allows them to cut ticket prices - which in turn will encourage more of us to fly.
Result: the airlines buy more planes anyway.
And some air travel experts believe carbon-fibre composites - in the quantities being used by Boeing - are far from tried and tested.
Phillip Butterworth Hayes, editor of trade publication Jane's Aircraft Component Manufacturers, believes the company is pushing the limits:
"They've got some very sophisticated systems on board," he says. "It's 50% composite materials - no-one has ever done anything like that on this sort of aircraft of this size.
DIFFERENT MODELS OF 787
The first will carry between 210 and 250 passengers up to about 9,400 miles (15,125km).
The second will carry between 250 and 290 passengers up to about 9,800 miles (15,770km)
The third will fly between 290 and 330 passengers on shorter routes, up to about 3,500 miles (5,600km)
"Secondly they are giving a lot of power to their subcontractors - design, development and integrating those sophisticated system, again something Boeing's never done.
"And thirdly, there's the timescale from rollout to delivering to the first airline customers. That's very tough."
But there are good reasons why it is worth Boeing's while to persevere.
The improved materials have other benefits: because carbon fibre doesn't rust, extra moisture can be added to the cabin air supply - reducing the "drying-out" effect that passengers often experience from the air conditioning in long-haul passenger jets.
The air supply will also be pressurised at a lower altitude.
And the strength of the shell allows for bigger windows. Boeing research suggests long haul passengers feel better when they can see the horizon.
All of which gives Boeing a boost in the battle with its European rival Airbus. The Toulouse-based company has a "Dreamliner" of its own - the A350, with its ultra-wide body.
But the A350 is not selling anything like as fast as Boeing's new baby.
So for now, the older hand in the aircraft game has the upper hand.