Ron and Harry and that flying car

[kennyg1864]

No: HPFGUIDX 187096

(apologies if this has been discussed before, but I couldn't find it on a search)

After watching CoS with my young already-a-HP-fan daughter (who shares Harry's and JKR's birthday!), I went back to a few passages in the book.

And it occurred to me...

How did Ron and Harry get onto the Hogwarts grounds??

We know from GoF that DD placed charms around the entrances.  We also know that even in the first three books that the students are safe at Hogwarts.  And of course, no one can Apparate into Hogwarts.

1. Maybe DD's charms are keyed to students and staff?  But even if they are, it seems that everyone has to enter via the front gate or via the boat docks (except for the Marauder Map's entrances, but those are all underground).  AFAIK no one (even staff) flies in via broomstick.  It would be inconsistent to prohibit Apparition but not broomsticks.

2. Side question: By the time of HBP, are DD's charms enhanced, or are they the same as they've always been?  IIRC even the Marauder's Map's entrances are sealed off, although I don't remember if it's only sealed off to "outsiders".

Still, we're left with the notion that a flying car can traverse DD's perimeter.  So why can two students come in via Ford Anglia, but no one can saunter in from Hogsmeade (or elsewhere) by broomstick or Apparition, but only via the front gates?

Maybe DD already knew from the headcount of students coming off the Hogwarts Express that Ron and Harry weren't on the train.  And maybe he deduced (from the Evening Prophet) that Ron and Harry were the likely drivers.  And maybe he had a special Anglia-sized hole in the perimeter charm.

But that's a lot of maybes.

'tis odd that JKR didn't address this with a throwaway line like "Professor Dumbledore's charm detected your approach, and he allowed you onto the grounds, else you'd have likely bounced onto the front steps of Honeydukes!"

kennyg1864