Hi Cathy , you can go online to the United Air Charter website and book online you then also get a 10% discount.
Bk on the day minimum 4 people to make it viable
On the day is fine subject to 4 people booking to make it viable
We booked around 2 weeks ahead of time but others seemed to just show up on the day - and had to take their turn to get on. As flights are very weather dependent - its best to book for the first day of your stay so that if there are weather related cancellations of flights you still have the chance to re-book for another time before leaving the area
We booked six months in advance as part of a complete package, but when we got there we upgraded to a longer flight and there was plenty of availability. I think you can arrange it when you get there, as it will always be dependent on the weather, so there's no guarantees either way.
I booked six months in advance, when I made my other trip reservations. Generally, winds/turbulence are less likely during morning flight hours. So if you want to be assured of a morning flight, I would book at least a month in advance. I also suggest that you request a seat next to the pilot for at least one in your group for best pictures.
We booked about 3 weeks in advance, but it seemed to me that there was plenty of space throughout the day. Really depends if you're going in low or high season.
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