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A hovercraft doesn’t fly not because the wing in ground effect but because it doesn’t have 6 degrees of freedom which constitutes flying. A sub or a torpedo ca
by dogma1138 6y ago
A hovercraft doesn’t fly not because the wing in ground effect but because it doesn’t have 6 degrees of freedom which constitutes flying.
A sub or a torpedo can fly through the water just like an airplane or a missile do through air.
- SideburnsOfDoom 6y agoDoes an ekranoplan "fly" then ?
- dogma1138 6y agoCan it move in 6 degrees of freedom?
- SideburnsOfDoom 6y agoI have no idea what that means, that's why I asked.
- dogma1138 6y agohttps://en.wikipedia.org/wiki/Six_degrees_of_freedom https://en.wikipedia.org/wiki/Six_degrees_of_freedom If not it isn't really flying. I don't know if it moves around with forces in 6DOF or not either.
- SideburnsOfDoom 6y agoUp to a max altitude of 7 meters (at best), sure, an Ekranoplan has got all the degrees of freedom that other aircraft have, Which as was pointed out here https://news.ycombinator.com/item?id=24629545 https://news.ycombinator.com/item?id=24629545 , is not 6 Imho no, an Ekranoplan does not fly freely. Nothing to do with a bogus DOF count though
- barumi 6y ago> 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.
- treetoppin 6y agoI guess I'm confused. If an aircraft can't go backwards or do a loop, does that mean it's not flying? Because as far as I know, every fixed wing aircraft is incapable of going in reverse, and most can't do a loop. Not trying to pick on your defenition of flight based on degrees of freedom, but that doesn't seem to match any definition of flight I've run across.
- bfuclusion 6y agoThe only reason an Ekranoplan can't fly higher is it's wings don't generate enough lift out of ground effect. Load a 747 up high enough, and it too wouldn't be able to get out of ground effect, but I'd still say it was flying.
- SideburnsOfDoom 6y agoYou can't just say that "because it's a 747, it can fly": 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.
- _Microft 6y agoWhere did you get this idea of flying? I wondered if I had a misconception there but any source I could quickly find on the web disagrees with the "can move with six degrees of freedom" definition and uses a definition like "doesn't touch ground or sea while moving through the air" instead. (Wikipedia on "Flight" / "Ekranoplan" / "Ground-effect vehicle", Merriam Webster on the word "Flight", and search for "what is flight" if that's not enough).
- karmakaze 6y agoFlight is typically 4DOF: (throttle, pitch, roll, yaw). There is no horizontal or vertical 'strafing' ability.
- KineticLensman 6y agoThe platform can move in the vertical and horizontal, e.g by exploiting a crosswind.
- robotresearcher 6y agoHelicopters and hummingbirds fly. And flies, they fly too. And there are a lot more flies flying than planes.