Anti-shock body

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NASA Convair 990 with antishock bodies on the rear of the wings.

An anti-shock body (also known as Whitcomb body or Küchemann carrot) is a pod positioned on the leading edge or trailing edge of an aircraft's aerodynamic surfaces to reduce wave drag at transonic speeds (Mach 0.8–1.0).

Wing trailing edge[edit]

Antishock body serving as flap track fairing under the left wing of a 747-100

Most jet airliners have a cruising speed between Mach 0.8 and 0.85. For aircraft operating in the transonic regime (Mach 0.8-1.0), wave drag can be minimized by having a cross-sectional area which changes smoothly along the length of the aircraft. This is known as the area rule, and is the operating principle behind the design of anti-shock bodies. Reducing wave drag improves fuel economy.

Anti-shock bodies, apparently developed in TsAGI and serving dual purpose as undercarriage bogie fairings, were first applied to Tupolev Tu-16 ''Badger'', that flew for the first time in April 1952, and were to remain a unique feature of the company's products up to and including the Tu-154.

In the West the theory was developed in the early 1950s by Richard Whitcomb at NASA, and Dietrich Küchemann at the British Royal Aircraft Establishment, leading to their appearance on aircraft such as the Convair 990 and the Handley Page Victor B.2 bomber.

Modern jet aircraft use supercritical airfoils which decrease wave drag significantly. Further optimization can be achieved through careful design of wing body fairings, engine nacelles, flap track fairings, and tip tanks. Due to the prevalence of supercritical airfoils, other design features with the sole purpose of minimizing wave drag (such as the anti-shock bodies on the Convair 990) are rare in modern aircraft.

Leading edge root[edit]

Anti-shock body on the tail of a Hawker Sea Hawk

On the Hawker Sea Hawk, the first prototypes experienced high tail drag when approaching transonic speeds. To resolve this, an anti-shock body was subsequently fitted to the leading edge of the junction between tail fin and stabiliser.


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