How do I fly with the vultures?

Hint 1 of 5:

You need to be able to summon the vultures, and to be able to hang
onto them as they fly.

Hint 2 of 5:

You need the whistle from the cereal box in the General Store.

Hint 3 of 5:

You'll also need the magnet from the door on Canuk's hut.