LOUISVILLE, Ky. (WDRB) -- Disappointing news for this year's Thunder Over Louisville Air show.

The Kentucky Derby Festival says the United States Air Force Thunderbirds will only be able to have two jets in the show. They will not be performing an hour-long aerobatic demonstration with six jets as scheduled.

That's because the FAA re-evaluated approval due to "obstacles" in the area.

KDF CEO Mike Berry says it's a disappointment, but added: "We appreciate the commitment that they made because I guess if they wanted to they could have said, 'hey we're not coming at all ... but that's not the case.

The Thunderbirds 15-person crew will still make public appearances.

The Golden Knights Paratroopers, the Kentucky Air National Guard's C-130, and the U.S. Marines Harrier demonstration will still be a part of the show.

The FAA released this statement:

The Federal Aviation Administration (FAA) determined that an aerobatic box that is 4,000 feet long by 1,800 feet wide, up to an altitude of 16,000 feet will provide a safe environment for Thunder Over Louisville spectators and airshow performers.   Aerobatic pilots will remain in the airbox, and avoid the new bridge construction that is about ½ nautical mile east of the eastern end of the aerobatic box, the K&I Railroad bridge,  which is west of the box,  and the 2nd Street/Clark Memorial Bridge, which is east of the box. Also, aerobatic aircraft maneuvers will directed away from spectators, who will be a minimum of 1,000 feet from the edges of the aerobatic box.   
Category I aerobatic aircraft, which includes high performance jets, require aerobatic boxes that generally are 3,000 feet wide. The Thunderbirds, Blue Angels, and Canadian Snowbirds require a length of 12,000 feet (2 nautical miles.)

The FAA closely reviews all airshow applications to ensure that the proposed operation can be conducted safely. 

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