I know the differences between old cockpits and new glass cockpits.

But how come a DC-9 pilot can use his DC-9 rating on an MD-90 and a 737-200 pilot uses his universial 737 rating on a newest 737-900?

Why does a DC-10 pilot need a new type rating for the MD-10?

Or why do they let DC-9 pilots and 737-200 pilots fly on MD-90 and 737-900 without new type ratings?

"For you"....?
Oh - they just tried to trick you in Long Beach -
Be happy -you now published another question on Y!A -

They probably used a different yardstick -
Was a rainy day when they measured the MD-11, it did shrink because of water -
Or they made a mistake when converting from metric measures...

Visual illusion because the MD-11 is longer - makes the fuselage proportion appear narrower
"Narrower" is easier to write than "more narrow" -

Instead of "anonymous blue face", I recommend you adopt a new name - "Hawkeye" maybe...?

You don't. Navigational planning is all done in 2 dimensions, exactly as if you were traveling on the surface.
The only factors from movement in the 3rd dimension that is accounted for is the difference is speed when climbing vs speed in cruise and the effects of the thinner air on true airspeed.

Every aviation chart I've ever used was a flat, 2 dimensional piece of paper

Back in the day, you needed to have a flight engineer for aircraft over a certain weight or complexity. It came from the days of flying boats and four engine bombers where the number of engine and systems controls were simply too much for pilots to handle.

Twin engine aircraft like the DC-3 and Convair 240 didn't need flight engineers because they were simple enough... and when the 737 and DC-9 came out they didn't need flight engineers either... but three and four engine airliners still needed them even though they were much more simple than a DC-6 or Constellation.

As aircraft became more automated WRT to systems with thing like EICAS to alert crew of problems, flight engineers were no longer needed.

I don't know about the DC-10, but the 727 certainly needed a flight engineer to do things like balance fuel loads by cross feeding, manually synchronize and tie generator busses together, control pressurization, and monitor optical cargo smoke detectors.

Israel is very conservative about overflight permits, from anywhere! It does not matter where the aircraft is from or who it belongs to, if you are not on a scheduled service to an Israeli destination, with a damned good reason to be going there, then there is no way you will get one.

Flights originating from Arab countries are barred from Israeli Airspace.

Private flight overflying Israel is not permitted, it is far easier to get permission to overfly Saudi Arabia than Israel.

It is nothing to do with any policies of the departure country, it is Israel's rules, which they are free to make.