Editing Wave drag (section)

=== Reduction of drag ===

A number of new techniques developed during and just after [[World War II]] were able to dramatically reduce the magnitude of wave drag, and by the early 1950s the latest [[fighter aircraft]] could reach [[supersonic]] speeds.

These techniques were quickly put to use by aircraft designers. One common solution to the problem of wave drag was to use a [[swept wing]], which had actually been developed before World War II and used on some German wartime designs. Sweeping the wing makes it appear thinner and longer in the direction of the airflow, making a conventional teardrop wing shape closer to that of the [[Nose cone design#Von Kármán|von Kármán ogive]], while still remaining useful at lower speeds where curvature and thickness are important.

The wing need not be swept when it is possible to build a wing that is extremely thin.  This solution was used on a number of designs, beginning with the [[Bell X-1]], the first manned aircraft to fly at the speed of sound.  The downside to this approach is that the wing is so thin it is no longer possible to use it for storage of fuel or landing gear.  Such wings are very common on missiles, although, in that field, they are often referred to as "fins".

Fuselage shaping was similarly changed with the introduction of the [[Area rule|Whitcomb area rule]].  Whitcomb had been working on testing various airframe shapes for transonic drag when, after watching a presentation by [[Adolf Busemann]] in 1952, he realized that the Sears-Haack body had to apply to the entire aircraft, not just the fuselage.  This meant that the fuselage needed to be made narrower where it joined the wings, so that the cross-section of the entire aircraft matched the Sears-Haack body.

[[File:Convair 990 on ramp EC92-05275-30.jpg|thumb|right|The [[Convair 990]] had particularly obvious [[Anti-shock body|anti-shock bodies]]; modern airliners usually have more subtle shaping for area ruling.]]
Application of the area rule can also be seen in the use of [[anti-shock body|anti-shock bodies]] on [[transonic]] aircraft, including some [[jet airliner]]s. Anti-shock bodies, which are pods along the trailing edges of the wings, serve the same role as the narrow waist fuselage design of other transonic aircraft.