The northern edge of Carowinds is around 5.7 nautical miles (34,800 feet) from the southern edge of the nearest runway. In a
recent (early last year) similar issue, the FAA recommended cutting some building proposals in the Miami airport flight path down from 1,000 feet to around 470 feet because the buildings were 5.7 miles (5 nautical miles) from the runway.
The
federal code seems to suggest that anything under 499 feet would be allowable at Carowinds without needing a waiver. A simplified presentation of the regulations can be found
here.
Objects are considered obstructions at the following heights (above ground level or above airport level, whichever is higher; in this case, Carowinds is at an elevation lower than the airport):
Within 3 nautical miles: 200 feet
3-4 nautical miles: 300 feet
4-5 nautical miles: 400 feet
Above 5 nautical miles: 499 feet
This is not to say that I think Carowinds will build a 400 foot tall coaster (I don't, at least not anytime soon), but I don't see how the FAA is an overwhelming barrier.
Anyway, I remember someone saying that there is a height limit at SFoG and that's why they don't have anything over 200 ft...Does anyone know if that's true, and if so..why? A bit off topic, sorry.
SFoG is around a mile from the end of the runway at Fulton County Airport, so anything over 200 feet there would be considered an obstruction and would have to be approved by the FAA.