Aerobatic Flying:Admixture of Freewill and Adrenaline
Aerobatics is the amalgamation of two words i.e. Aerial and Acrobatics. Aerobatic is the practice of flying maneuvers that involves flying an aircraft at ridiculous angles that are not used in normal flight. Aerobatics are performed in airplanes and gliders for training, entertainment, and sport. Additionally, some helicopters, such as Westland Lynx are capable of performing loops and rolls. Aerobatics flying gives freedom to adrenaline junkies to test their limits and also test their aircraft structural strength. Every loops or spin takes a toll on a pilot’s body. The fitness level required is higher than what is needed to do a normal flight. The loss of consciousness because of positive g-load factor or burst blood vessels due to negative g-load factors result from sustained high load factors demand pilots to be more physically strong. Military pilots provided with” g-suits” that help them keep blood in their heads during positive load factors, whereas aerobatics pilots in competition use muscle tensing and reclined seats .A pilot’s tolerance to g-loads increases with practice. The maneuvers can be performed solo or as a team. The Red Arrows officially known as the Royal Air Force Aerobatic Team is the most famous acrobatics team in the world performing for more than 50 years.
An aerobatics aircraft must have high tensile strength to bear that high g load factor. It must be very stable and responsive to make that death defying stunt look smooth. In order to get aerobatic certification in United States, an aircraft must be able to withstand g-load factors from minus 3 to 6 without any risk of permanent deformation. The aerobatic aircrafts which take part in competition are able to pull off up to 12 g load factor. Aerobatic maneuvers flown in a jet-powered aircraft are limited in scope as they cannot take advantage of the gyroscopic forces that a propeller driven aircraft can exploit. Jet-powered aircraft also tend to fly much faster, which increases the size of the figures and the length of time the pilot have to withstand increased g-forces. Jet aerobatic teams often fly in formations, which further restricts the maneuvers that can be safely flown.
Some of the popular aerobatic maneuvers are:
A loop is one of the most practiced and most enjoyable aerobatic maneuvers, but high skill is required to perform it safely and perfectly. The pilot must enter the loop with ideal speed and angle in order to demonstrate smooth maneuver. If the pull-up is made too abruptly, the aircraft is prone to high-speed stall and won’t be able complete the top of the loop. If the pull-up is too gradual, or if inadequate speed is there, the aircraft will run out of speed and fall inverted out of the maneuver.
A smooth but non circular loop requires a g-load factor of 3 to 3.5, whereas a competition-quality circular loop may require a g-load factor of 6.
Snap Roll/Flick Roll
In England, it also known as a flick rolls. A snap roll uses the same control inputs as the spin but the controls are applied with power on in snap roll and at speed well above the un-accelerated stall speed. The resulting differential lift produces a rapid roll that can be very difficult to stop at a precise point. A certified aerobatic aircraft can perform 3 or more consecutive snap rolls, both upright and inverted, before the axis of the roll changes excessively and the roll degenerates into a power spin.
Hammerhead Stall/ Stall Turn
In the hammerhead stall (English name is stall turn) the aircraft is pitched straight up with power on until its nose is pointing straight up and just before the aircraft runs out of airspeed, full rudder is applied to rotate the nose to either right or left and the rotation is stopped when the aircraft is heading straight down.
Aileron Roll/Barrel Roll
The most pleasant to eye rolling maneuver is the aileron roll. It is also known as the barrel roll. It is performed through the coordinated use of the rudder and ailerons. It begins with a climbing steep turn to a 90-degree bank, allowing the nose to fall below the horizon by reducing elevator pressure as the roll continues to inverted flight and then recovering by increasing the elevator pressure back to upright flight. The nose will trace out a sort of circle around a point on the horizon.
The legendary Spanish aerobatic pilot Colonel Jose Luis de Aresti Aguirre developed a shorthand notation (method) to measure difficulty level for aerobatic maneuvers. First published in 1961, Aresti symbols have become universally accepted to outline aerobatic routines for both air shows and contests. Each figure in Aresti’s dictionary includes a difficulty level or “K” factor by which judges’ score in contests.
The FAI World Aerobatic Championships (WAC) is a competition in sport aviation organized by the Fédération Aéronautique Internationale, the world air sports federation.