Questions on Shuttle entry/landing

[ar81]

When you are in orbit, you find yourself that the closest pass could be 500km from Canaveral base.
Aligning that is awful for it takes lots of fuel, even if you are at 90 degrees from Canaveral to maximize efficiency of
fuel usage.

With such misalignment AutoFCS ends up crashing the ship.
I have noticed that distance of closest pass seem to vary in time like a sine function.  It means that it may never pass
closer than 500 km, because in every pass your orbit seem to move about 1000km.

1.How do real astronauts align orbit with base for deorbit and entry?

2.what is the proper distance for deorbit burn?
I heard that deorbit at the opposite of the planet works for a cold reentry, but due to thermodynamic properties it is
not good for shuttle, because you have low but continued heat exposure which would melt the hull once on the
ground.

If you are too close, the entry angle would be too steep and it would fry the ship.
So it seems there must be an optimal distance to start entry.

3.What is the proper altitude for deorbit?  Being too high orbit, or highly elliptical orbit would fry your ship.
I have fried some DGIVs that way when attempting to return from the moon without lowering my orbit.

4.Entry seems to start when you have a minimum of dynamic pressure.  When does it end?

[Pagir]

In fact, just wait: a future orbit will bring you just above the Cape. It will be far less
But in fact, it is useless to wait: the "real" (and virtual) shuttle can (by banking the spaceship), correct any
crossrange shorter than 1 500km during atmospheric reentry! This is to have at least two orbit in a row to make a
reentry.

I suggest you practive with the automatic system of the 3.9.4 shuttles before trying manual reentry!

Pagir

[ar81]

Yeah, 3.9.4 comes with AutoFCS, which starts deorbit in the opposite side of the planet.  And it crashes the ship if the
base is not aligned by 500 km.