DAYTON, Ohio (AP) - The U.S. Air Force's grounding of its Thunderbirds jet demonstration team has put the popular flight event's appearance at this summer's Dayton Air Show in jeopardy.

The Air Force announced Friday it planned to ground the Thunderbirds if a federal budget deal wasn't reached. The team will cease air support to public events April 1 unless something happens to get the budget back on track.

Democratic President Barack Obama and congressional Republicans, led by U.S. House Speaker John Boehner of Ohio, were unable to reach a deal Friday. Boehner's district borders Dayton.

The Thunderbirds were scheduled to appear at the Vectren Dayton Air Show on June 22-23. The show's executive director told the Dayton Daily News (http://bit.ly/13tFxqB ) he remains hopeful the Thunderbirds will be able to appear since pilots are still expected to continue to fly this month to keep up their cockpit skills.

"The show is going to go on regardless," said director Terry Grevious. "We've had a number of years where we haven't had a jet team."

Grevious said toughly every four years the air show takes place without either the Air Force's Thunderbirds or the U.S. Navy's Blue Angels.

Uncertainty this year over whether the jet teams would be flying has prompted several air shows around the country to cancel, however, including one in Indianapolis.

The Air Force said flying hours normally set aside for its demonstration acts, including the Thunderbirds and the F-22 Raptor, are being reserved for national readiness activities. The service projects automatic budget cuts will mean the reduction of 203,000 flying hours, a fifth of the total.

The order involving public events also applies to Air Force Reserve and Air National Guard aircraft, the newspaper reported. That means no flyovers at funerals, military graduations, heritage flights, sporting and other events, the service said. Stationary displays of aircraft could continue.

Events that remain scheduled at the air show include first-time Dayton appearances by a MiG-17F, a "high-subsonic jet aircraft" used by the North Vietnamese, and a North American F-86 Sabre jet that entered U. S. Air Force service in 1949.

Others named earlier to the show's lineup include the Birmingham, Ala.-based AeroShell Aerobatic Team. The show also will feature a jet-powered school bus and the flying B-29 Superfortress known as "FIFI."