How large would spinos wings need to be for it to fly?

[Lynx]

You all have likely heard of the ridiculous flying Spinosaurus theory. A joke started by a group of people that slapped pterosaur wings onto Spinosaurus in order to make fun of the Quad vs Bipedal argument. To put it short, instead of finding arms, the paleontologists describing Spinos arms found wings.  It would assault creatures from the air to hunt while also being adapted for swimming, kind of like an Albatross or Puffin.

However, this made me curious. In all seriousness, how large would Spinosauruses wings have to be for it to fly? Would it be able to soar through the air, or just barely glide above the ground? Could Spinosaurus take off from the water to air, or would it have to swim to shore?

[stargatedalek]

Something that heavy would soar better than it would glide or burst flight, which is rather exactly the reason such animals have trouble flying to begin with. It's less a matter of required wing size to stay aloft and more sheer ability to move fast enough to get off the ground.

If we assume Spinosaurus was able to sprint fast enough to get into the air, it would need extremely sturdy wings, more like a bird than a pterosaur, and probably each about as long as its body. This is more relative to planes than birds, and moving any slower than a plane might just result in Spinosaurus dropping from the sky anyway, wing size aside.

[andrewsaurus rex]

it's FAR too heavy to fly.  Even giving it giant wings wouldn't help as it would need to fly very fast for its wings to create enough lift to keep it aloft, even if it were gliding off of cliffs, which would help solve the take off problem. 

A small aircraft, which weighs much less than a Spinosaurus, has a stall speed of around 125mph, which means below that speed the wings are not creating enough lift to keep the play airborne.  So a gliding Spinosaurus  would need to go at least that fast, probably faster because it's heavier and less aerodynamic in form than an airplane.

I'm not even going to mention flapping to stay aloft.  No chance it could fly that way no matter how big and efficient its wings.

The largest flying creatures that ever existed maxed out around 200 pounds, none were several tons.

[Lynx]

Could a juvenile spinosaurus fly, perhaps?