It's not completely useless, but the US military's existing transport aircraft are not exactly pushing the boundaries of fuel consumption. A regular 777 freighter will get quite a bit further. Ultimately the military don't care about the cost, have many refuelling options, and are relying on much shorter range aircraft in other aspects of any conflict. Plus unlike other areas of aviation, if you solve a range problem with a bigger fuel tank, you don't get beaten to death by the bean counters.
That's quite different from an airline, where a 20% saving in their largest expense against a 3% margin in a price competitive industry is game changing
That has been true, but the US military is now pivoting to confront China in the Western Pacific theater. This means an increased emphasis on fuel efficiency to boost unrefueled range.
Why then? Stealth can't be that good. Cost seems impossibly unlikely at a development stage, but are they somehow lower cost to manufacture? Seems unlikely.
I am welcome to alternatives, but the announcement included:
“Blended wing body aircraft have the potential to significantly reduce fuel demand and increase global reach,” said Secretary of the Air Force Frank Kendall. “Moving forces and cargo quickly, efficiently, and over long distance is a critical capability to enable national security strategy.”
It could be cleverly written to suggest it is about fuel efficiency and range, but that these straightforward and public explanations aren't the real reason. Totally possible, but what are they then? I know I don't know enough to second guess the public statements of the Secretary of the Air Force and the plain reading is that the first sentence is directly related to the second.
But we all know that's not how it works. Both sentences are just always true, they aren't necessarily related. I don't know what else it would mean though.
I could imagine that it makes a real impact to a bomber. I have read that WW2 planes essentially were loaded to the maximum allowable weight between the fuel + ammunition. If you can cut down the fuel for same range, that allows for more ammo.
That was, arguably, the consequence of poor accuracy and low bomb yields - those planes had to drop a lot of ordnance for there to be a chance something actually lands on the intended target. I recall reading somewhere that a single modern guided bomb would achieve the effect that, during WW2, required 100 to 1000 bombers.
That's quite different from an airline, where a 20% saving in their largest expense against a 3% margin in a price competitive industry is game changing