Soon after aircraft were invented, pilots realised that they could be used as part of a flying circus to entertain people or impress others in what was termed aerobatics. Manoeuvres that had no practical purpose were flown for artistic reasons or to draw gasps from onlookers. In due course some of these manoeuvres were found to allow aircraft to gain tactical advantage during aerial combat or "dog-fights" between two or more fighter aircraft. The word presumably derives from the term used by human gymnasts - acrobatics - to describe exercises designed to impress or build muscle strength.
The French aerobatic team - the Patrouille de France.|
Most aerobatic manoeuvres involve rotation of the aircraft about its fuselage - rolling - or the following of geometric patterns in the sky (most famously the loop). Formation aerobatics are usually flown by teams of up to sixteen aircraft, although economic considerations mean that most teams habitually fly between four and ten aircraft. Some are state funded to reflect pride in the armed forces whilst others are commercially sponsored. Coloured smoke trails may be emitted to emphasise the patterns flown and/or the colours of a national flag. Usually each team will use aircraft similar to one another finished in a special and dramatic colour scheme, thus emphasising their entertainment function. A few aircraft designs such as the Pitts Special and Sukhoi Su-29 have been optimised for aerobatic purposes, but trainer aircraft are normally employed. Famous teams include the Black Arrows, Blue Angels, Diables Rouges, Frecce Tricolori, Halcones, Patrouille de France, Patrouille Suisse, Red Arrows, Red Pelicans, Rothmans, Roulettes, Royal Jordanian Falcons, the USAF Thunderbirds and the Yellowjacks.
The practice of formation flying might have been inspired by the migration of flocks of birds, swans or geese. Certainly most aerobatic teams include a V-formation in their routines. Teams fly V-formations out of practicality - they can't fly directly behind another aircraft, or they'd get caught in the wake vortices or engine exhaust. Aircraft will always fly slightly below the aircraft in front, if they have to follow exactly in line.
Stearmans of the UK Utterly Butterly display team.|
Aerobatics may be taught to military pilots as a means of developing precise flying skills and may occasionally have value in a military context. Test pilots might attempt aerobatic manoeuvres in an aircraft designed for less adventurous purposes, simply in order to improve a manufacturer's understanding of its capacity to fly. Discovering how an airframe reacts to the stresses implied by sharp turns may be expected to assist companies or air forces in writing manuals for safe operations over the longer term. A safe operational envelope may be described setting out the limits within which future service pilots should endeavour to fly. Unfortunately some aerobatic manoeuvres end in accidents and these can result in fatalities amongst flight crew and onlookers. You are most likely to witness aerobatics at a public airshow.