Why arent airplanes designed more like hang gliders?

Yes, so why arent large passenger planes designed like navy transport aircraft?

Seems like a more stable design...and folks would get a better view.
Note how the wings are angled slightly towards the ground.

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It is advantageous from a safety standpoint to have gushing fuel (on a really bad day) falling below (not through and around) the cabin.

"Note how the wings are angled slightly towards the ground."

That anhedral diminishes the "Dutch Roll" effect of highly-swept wings. If you visualize swept wings in slipping or sideways flight (imagine being directly upwind in the photo above) you can see that the leading swept wing presents more span and creates more lift. Canting swept wings downward reduces excessive rolling forces when the nose slews to one side (in turbulence, with rudder application, or during asymmetrical thrust/engine failure).

High-wing airplanes require less dihedral (upward canted wing) effect, which couples roll with yaw in the same direction left or right- So it's typical for high&swept-wing airplanes to have a lot of anhedral built in.

 

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I didnt get half the buzzwords there, but heres another question.

Wouldnt the ideal engine configuration be two jets on either side of the tail?

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If one of them blows up, it seems to me that the plane would be easier to control with one functional engine close to the body, instead of out on a wing???

 

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"I didnt get half the buzzwords there"

Dihedral- mounting the wings higher at the tips than at the root

Anhedral- mounting them the other way (sloping downward spanwise)

"Wouldnt the ideal engine configuration be two jets on either side of the tail?

If one of them blows up, it seems to me that the plane would be easier to control with one functional engine close to the body, instead of out on a wing???"

Exactly: That layout has advantages when one engine fails: Less asymmetrical forces slewing the nose toward the bad engine. On the negative side, close-mounted engines are closer to critical control runs (cables and hydraulics) than engines on wing pylons.

Rear engines also have the structural disadvantage of putting heavy stuff at the rear, which requires relatively longer forward fuselage, and larger tail surfaces to balance things out. The best place for heavy things structurally is near the center (and center of mass) of the aircraft: When things pitch, roll, or yaw suddenly, it takes less structure to keep them where they belong if they're in close- just as it's easier to shake something heavy in your hand close to your chest, rather than way out at arm's length.

 

Seems that high wings usually tilt down...and low wings tilt up.

Is this a universal rule, or only on heavy craft?

 

It's fairly universal- with wings up high, there is an inherent dihedral effect (swing the nose left, wings tend to bank left, even with wings mounted flat). This is called "pendulum effect". Hang gliders have a lot of that (many of them too much IMO). Having the alternative happen (nose left- wings roll right) would be distinctly unpleasant, like riding a motorcycle that flings you over the top in every turn.

Inherently banking into a turn is a good thing for planes to do. But swept-wing airplanes (if not for Ann Hedral's steadying help) can overbank in response to yaw (yaw means left/right swinging of the nose, like when an airplane gestures "NO!"). Rolling hard in the direction of yaw can be too much of a good thing- banking the correct way, but too much. When I experience unintended left and right yawing and rolling in an airplane, I also tend to gesture "NO!" That's why many swept-wing and high-wing airplanes have droopy wings, so that they don't misbehave by wanting to roll too much into turns.

Airplanes flown by military and airline folks are very carefully designed to co-ordinate roll and yaw, because those poor sods aren't very good at using their hands and feet at the same time (they have trouble remembering that bank is left/right on the stick/wheel, and yaw is poking your left/right foot in). Airplanes designed for more adept fliers don't need all these fancy aerodynamic tricks- my Citabria dances gracefully through the air mostly because I'm masterfully finessing the controls. Today's big air-buses and bomb-haulers are designed to barge around the sky without any help from the button-pushers "at the controls". The big birds are so stable that they don't really need pilots- those people are just paid to put on uniforms and sit up front, looking smart for PR purposes.

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