Also, why is the BBC feeling a need to put quotes around "fly" in the article? If a person is, like, lifting off from the ground, and moving through the air in a controlled fashion driven by jet engines, isn't that pretty exactly flying, without quotes?
The BBC is fastidious about quoting. It's a good thing. They don't report that 'man killed by a speeding car' - instead they report 'man "killed by a speeding car"' because they're quoting their source that told them what happened, not telling you what happened themselves because they weren't there and don't know that.
It depends, are they reaching a height where the Wing-in-ground effect is negligible? If they have to stay below that, then no, not really flying. Unless you'd say that a hovercraft or ekranoplan also flies.
Or they could just be staying low because it might be insanely dangerous if the operator loses control at even slight altitude.
A sub or a torpedo can fly through the water just like an airplane or a missile do through air.
If not it isn't really flying. I don't know if it moves around with forces in 6DOF or not either.
Imho no, an Ekranoplan does not fly freely. Nothing to do with a bogus DOF count though
It seems that you don't understand the implication of the DOF count. Flying means moving freely through the air. That, colloquially, means 6degree of freedom movement through space. It means looping a, it means barrel rolls, it means it can run circles and go backwards and move upside down. You know, flying.
Ekranoplans fly as much as an hovercraft does, which mean they don't. Case in point: they are unable to do 6dof movement. An ekranoplan doesn't do barrel rolls for example.
A 747 with no fuel can't take off and fly.
A 747 with so much load that it never takes off at all, can't fly.
And IMHO, a 747 with just so much load that it can barely take off but can't get out of ground effect, also can't fly. It's borderline, but not really.
It's an academic distinction though. Give the 747 a while, and it will burn enough fuel to lighten and ascend.
The wing-in-ground effect. It’s a dumb little joke.