Flying in WAS Some questions

[bluesqueak]

Snow wrote:
> 
> (2) If the castle is protected from anyone flying into the grounds 
> (via Dumbledore and Harry flying into Hogwarts for the final 
showdown 
> on the tower), how did the Ford Anglia manage to get through the 
> magical defenses in COS?
> 
Pip!Squeak:
One very simple solution is that Dumbledore added to the defenses 
when Hogwarts started to develop that safe, tranquil air most noted 
in the East End of London during the height of the Blitz {g}.

So in Books 1 and 2 there might be no defenses against brooms. 
People can fly in. Why not? It's a normal mode of wizarding 
transport, much more visible than apparition. Allowing apparition 
would mean a thief could go straight to DD's office, say, and nick 
all the valuables. But you can see someone coming in on a 
broomstick. Really, it's the equivalent of someone driving a car in -
 why should they think to stop it in normal times? There's probably 
some standing request to check in at the office and not fly over the 
quidditch pitch in case you crash into a student, and that's it. 

But sometime during Books 3 to 6 Hogwarts is made a no-fly-zone - no 
crossing the walls on a broomstick. Sometime during these books 
(maybe after the QWC episode, or maybe during PoA) Dumbledore has 
protected the castle against aerial entry.
 
Changing the spells during PoA makes most sense; blocking flying 
means there's no way into the castle except the entryways Dumbledore 
knows about. 

Pip!Squeak
"Where do you think I would have been all these years, if I had not 
known how to act?" - Severus Snape