An air show (or airshow, air fair, air tattoo) is a public event where aircraft are exhibited. They often include aerobatics demonstrations, without they are called "static air shows" with aircraft parked on the ground. The largest air show measured by number of exhibitors and size of exhibit space is Le Bourget, followed by Farnborough, with the Dubai Airshow and Singapore Airshow both claiming third place. The largest air show or fly-in by number of participating aircraft is EAA AirVenture Oshkosh, with approximately 10,000 aircraft participating annually. The biggest military airshow in the world is the Royal International Air Tattoo, at RAF Fairford in England. Outline Some airshows are held as a business venture or as a trade event where aircraft, avionics and other services are promoted to potential customers. Many air shows are held in support of local, national or military charities. Military air firms often organise air shows at military airfields as a public relations exercise to thank the local community, promote military careers and raise the profile of the military. Air "seasons" vary around the world. The United States enjoys a long season that generally runs from March to November, covering the spring, summer, and fall seasons. Other countries often have much shorter seasons. In Japan air shows are generally events held at Japan Air Self-Defense Force bases regularly throughout the year. The European season usually starts in late April or Early May and is usually over by mid October. The Middle East, Australia, and New Zealand hold their events between January and March. However, for many acts, the "off-season" does not mean a period of inactivity; pilots and performers use this time for maintenance and practice. The type of displays seen at shows are constrained by a number of factors, including the weather and visibility. Most aviation authorities now publish rules and guidance on minimum display heights and criteria for differing conditions. In addition to the weather, pilots and organizers must also consider local airspace restrictions. Most exhibitors will plan "full," "rolling" and "flat" display for varying weather and airspace conditions. The types of shows vary greatly. Some are large scale military events with large flying displays and ground exhibitions while others held at small local airstrips can often feature just one or two hours of flying with just a few stalls on the ground. Air displays can be held during day or night with the