A view of a Van Gogh-inspired hot air balloon being inflated during the Philippine International Hot Air Balloon Fiesta at Clark Freeport Zone in Pampanga province, north of Manila February 12, 2015. According to the organizer, a total of 32 hot air balloons are part of the four-day event. (Photo by Erik De Castro/Reuters)

In this photo provided by Andreas Langreiter via Global-Newsroom, Hannes Arch of Austria performs during the finals of the first stage of the Red Bull Air Race World Championship in Abu Dhabi, United Arab Emirates, Saturday, February 14, 2015. (Photo by Andreas Langreiter/AP Photo/Global-Newsroom)

Hot air balloons take part in the 38th International Balloon Festival of Chateau-d'oex, Switzerland, 23 January 2016. For nine days balloonists from 15 countries take part in the ballooning event in the Swiss mountain resort famous for ideal flight conditions due to an exceptional microclimate. The festival takes place from 23 to 31 January. (Photo by Cyril Zingaro/EPA)

A man photographs the main engines of the space shuttle orbiter Discovery on display at the Udvar-Hazy Smithsonian National Air and Space Annex Museum in Chantilly, Virginia August 28, 2015. Shuttle Discovery had 27 years of service and flew 39 times before being retired in 2011. (Photo by Gary Cameron/Reuters)

A plane carrying a wing walker crashed at an air show and exploded into flames Saturday, killing the pilot and stunt walker, authorities said. The crash of the 450 HP Stearman happened at around 12:45 p.m. at the Vectren Air Show near Dayton in front of thousands of horrified spectators. No one else was hurt.

Photo: A wing walker performs at the Vectren Air Show just before crashing, Saturday, June 22, 2013, in Dayton, Ohio. The crash killed the pilot and the stunt walker instantly, authorities said. (Photo by Thanh V. Tran/AP Photo)

A military AWAC aircraft lands at the British RAF Akrotiri airbase on March 20, 2011 in Cyprus. Defence analysts said the sovereign military airfield at Akrotiri could be used by the RAF to help enforce a no-fly zone over Libya against Col Gaddafi’s offensive against outgunned Libyan rebels. (Photo by Matt Cardy/Getty Images)

A Polish MiG-29 flies beneath dark skies at the annual RNAS Yeovilton Air Day on July 9, 2011 in Yeovil, England. The annual air day at RNAS Yeovilton in Somerset, attracts over 35,000 people to what is one of the biggest air shows in the region and gives visitors the chance to see a host of aircraft as well as a number of historic and classic cars. (Photo by Matt Cardy/Getty Images)