Boeing has flown the X-48B Blended Wing Body technology demonstrator at NASA Dryden in California. The company did not immediately announce the 21 July flight because its quarterly earnings release - including an extra $500 million in R&D expenses for the 787 - got in the way.
The company might also be a little concerned that, as has happened more than once before, someone will look at the BWB and see Boeing's next airliner. Now who would do a thing like that?
It's only a model...
McDonnell Douglas began working on the BWB before it became part of Boeing in 1997, and its original design concept was an 800-passenger airliner capable of flying more than 7,000nm. A radio-control model was flown by Stanford University in 1997, when service entry in 2010 was seen as doable.
Work continued under Boeing, looking at different sizes of both passenger and cargo aircraft. In each case, the flying-wing aircraft's efficiency figures were way better than conventional tube-and-wing designs. But the commercial folks in Seattle were always wary of the BWB and the project ended up within Boeing's Phantom Works research organisation, its focus shifted towards a military tanker/transport.
Plenty fuel for thought
There were several reasons for the shift. First, there remain genuine concerns about passengers accepting the windowless cabin and the rectangular pressure vessel being producible. Then there were the perceptions that the BWB would compete for precious resources with other Boeing commercial programmes, including 747 and 777 derivatives.
So Boeing began insisting the BWB was a military project. With its huge internal volume, the aircraft would make a great airlifter and the flying wing could carry not one but two or three refuelling booms, making it an unrivalled tanker. It was the defence-oriented Phantom Works that designed the subscale X-48B to investigate the low-speed handling and complex flight controls, with the UK's Cranfield Aerospace building the two unmanned demonstrators.
Then, earlier this year, I was surprised to hear George Muellner, head of advanced systems for Boeing's defence business, say he believed the launch customer for a BWB would be a commercial freight operator. Not surprised by the interest - FedEx has made no secret of its studies of a BWB freighter - but that the commercial market had again come to the fore.
Muellner went as far as saying Boeing was working with a couple of customers and had defined a commercial BWB freighter with one of them. Of course, he meant "potential customers" (to a defence company a customer is always a customer even if they never buy anything). He also made clear any launch depended on customer financing and Boeing's willingness to invest, and any aircraft would take 10 years to develop.
But, predictably, Muellner's remarks provoked a testy reaction from the commercial folks in Seattle, who pointed out that Boeing already has a couple of very nice commercial freighters, thank you, in the 777F and 747-8F.
All this highlights a couple of things. One, that it is very hard to do research into enabling the next generation of aircraft without calling into question the viability of the current generation. Two, that the BWB is not going to go away. The Cambridge-MIT Institute's Silent Aircraft Initiative has made a compelling case that the BWB is the most environmentally friendly configuration out there.
And Boeing knows it.