wich way up does a bird fly?
488706
Which ever way it is facing. Unless there is a strong head wind.
1182585
Technically, depending upon the type of airplane and speed of the head wind, a plane can "hover".  As long as air moves over the surface of the wing fast enough to create enough lift to make the airplane fly, it will fly--it just may not have very much forward speed.\nWhy does an airplane fly?  The Bernoulli principle.  Air flowing around the wing does so at two different speeds due to the shape of the airfoil.  It flows around and over the top more quickly than along the flat bottom of the wing.  This creates higher pressure on the bottom pushing up.  As long as there is enough push to overcome gravity (or weight), the plane will fly. You might ask, then without moving forward and in no wind, how does a helicopter fly?  Well, its airfoils are always moving through the air as long as it is running--the rotors are its wings.
1086852
It is hard-wired into their brains but the younger birds start out by following their parents south and if birds are taken out of the wild at a young age and have never migrated a small glider type plane can be flown the the birds will follow so it can be learned too.
406562
a bird, because it would be awesome to fly!!
1141613
It depends on the distance the bird is from the person. The bird could be at 60 degrees from him, and be just a few inches above him.
532167
The fly get's very close to the ceiling, then put's up it's two front legs.  These legs grasp the ceiling and the fly does a "handstand" and flips over.
580440
Birds. Just to fly they'd need more brain power.
746359
Why does a bird fly?  A fish swim?
886536
If only birds really could fly in vacuums, but this is physics class world, not real world, so...\n\nIn the x direction the fish has a velocity of 18 m/s\nThis won't change according to Newton's laws.\n\nWe are interested in knowing how fast the fish is going when it hits the ground....I assume the bird dropped it.\n\nWhen the bird is carrying it it has 0 velocity in the y direction.\n\nWe know the height it falls from and the acceleration so we can use the equation below to find the final velocity in the y direction\n\nv = sqrt[V^2 + 2hg]  where V is the initial velocity in the y direction so\n\nv = sqrt[2*5.4*9.81]\nv = 10.293 m/s\n\nWe use the pythagorean theorem to add the vectors \n\nspeed = sqrt[18^2 + 10.293^2]\nspeed = 20.735 m/s
512347
Generally it's called a V formation, and it's usually geese (Canada geese are common geese that you'd see). Ducks also fly this way, although I usually see them in pairs.\nBirds fly this way because it's more aerodynamic. The bird in front is essentially plowing the way through for the rest of them. The ones behind fly in its "wake". They take turns being the lead bird since that's the hardest position to be in.
964669
If it has wings it's a "fly"\nIf it doesn't it's  "grounded"!!! \nThat was a cute question. I'd never thought of that....LOL ;o)
284704
a bird can not fly to great heights with out wind. when someone reaches a high level of achievement then the person or persons who have aided them in this accomplishment are said to be "the wind beneath my (the achievers) wings"
1031888
Flys don't move with the lift.  If the fly is in the air when the lift starts moving up, the fly must also move up -- or it will end up on the floor.  If the fly is perched somewhere on the lift wall, then it will gain momentum with the lift.  If the fly releases itself from the wall, it first has no problems because it is traveling at the same momentum as the lift, but it immediately starts to lose the momentum and must again fly in the same direction as the lift.\n\nTHE FLY IS NOT HELD IN PLACE BY THE AIR IN THE LIFT.
117781
Certainly possible in theory. I doubt if anyone has ever done it in practice.\n\n\nRemember that a plane stays up in the air because of the speed that the air moves over its wings, not beceuse of how fast the plane moves relative to the ground. If a plane turns into the wind it can generate the same lift while travelling slower relative to the ground. With a strong enough headwind it is quite possible for a plane to remain stationary and airborne\n\nBut as I said, this is only theoretically possible. I've seen light planes do this and hang-gliders and birds do it all the time. But it would be incredibly dangeorus for a 'passenger flight'. If the wind were to drop, even for amoment, the plane would immediately stall and fall from the sky. It's fairly easy for a light plane or glider to recover from such a stall, but a large commercial passenger craft would find it much harder. There's a good chance it would crash.
803574
It means to travel through the air.  A bird does this by the "lift" of the air under its wings.  Planes use the same method, but must be moving fast enough and so are propelled by engines.\n\nIcarus flew with wings made from bird feathers that were held together by wax.  He flew too close to the sun and.... well... if you don't know it, you can guess the rest of the story.\n\nTo fly an also mean to be free.  Let yourself FLY!  Unhindered and with reckless abandon.\n\nSue
64483
Mamals (teradactyles) used to fly with leatherlike wings so it would seem that humans could also.  However human arm and chest muscles are not very suitable for flight.  As in the term pigeon or chicken breasted, birds have muscular chests that fascilitate a powerful downward pull on the wings.  Coonsider the shape of a turkey breast and the thick breastmeat there.  Still, the only way a turkey can soar with the eagles, is in their talons.  We would tire too easily, even with very light fake wings.
1176488
Well, ounce for ounce, the bird's skeletal frame is extremely strong and light.  But what allows it to fly is a combination of things.  First of all the birds' muscles are totally different than that of a humans' which can be trained to do short sprints or long distance running or both. The birds' primary movement is flying and depending on the bird, they can fly long distance or fly quickly.  Most can not be a jack of all trades and fly long distance like a wild geese and be as quick as a sparrow.  \n\nSecondly what allows a bird to fly is a totally different internal organs compared to a bird.  Many birds have several pairs of lung like features that allows them to utilize oxygen extremely efficiently.  Also a birds digestive system is made so that it craps every 30 minutes or so after food intake.  This allows to minimize the body weight thereby allowing it to fly easier.\n\nThe feathers which are stream lined are what actually allows a bird to fly, but I would say that is just one aspect of WHY it can fly.    Take the ostrich.  It can not fly at all.  Take the Toucan.  It has streamlined feathers but it can not fly all too well either.\n\nHope that helps.