airfoil technology
piston aero engines
jet engines
slotted wings and wing additions
development of swept wings
Horten flying wings
Northrop flying wing
forward-swept wings
delta wings
variable-sweep wings
supercritical airfoil
the monoplane
variable pitch propellers
metal skinned aircraft
retractable landing gear
NACA engine cowling
stealth technology
aviation fuel
aerial refuelling
aircraft noise reduction
V 2 missile technology
early X Planes
X15 and hypersonics
Nord Gerfault X-plane
lifting bodies
VTOL and STOL Aircraft
Soviet composite Aircraft
technology of landing
technology of navigation
development of autopilots
aircraft simulators
advanced aircraft materials
Unmanned Aerial Vehicles
Nuclear powered aircraft
the area rule
air defence

The Area Rule: Richard Whitcomb Concept

Raul Colon
PO Box 29754
Rio Piedras, Puerto Rico 00929

This is the story of a brilliant young engineer who would radically change the way aircraft were to be designed in the future. A story about a radical new idea in aircraft development: the Area Rule Concept. More importantly, this is the story of a man and a concept that combined, would revolutionise the aircraft designs forever. Richard T. Whitcomb was born in the small town of Evanston, Illinois on February 21st, 1921. Since early in his childhood, Whitcomb was influenced by his paternal grandfather who had known the great American inventor Thomas A. Edison. He would sit with his grandfather for hours and hear him tell story after story about the great inventor’s life. Such was the influence of Mr. Edison in young Whitcomb life that he decided to study mechanical engineering right after high school. He enrolled at Worcester Polytechnic Institute. He proceeded to graduate with honours with a degree in the complex field of mechanical engineering. In the summer of 1943 Whitcomb was hired to perform data gathering tests on the famous National Advisory Committee for Aeronautics, Langley Aeronautical Laboratory at Hampton, Virginia. Young Whitcomb did not know it at the time, but his work at the prestigious laboratory would eventually lead him to become one of America’s premier aerodynamic engineers. His innovating designs would launch a new era in America’s aircraft design.

The late 1940s saw Langley’s wind tunnels used extensively on high speed research. Test pilot Chuck Yeager broke the sound barrier in 1947 with a Bell X-I test aircraft, first tested on Langley’s wind tunnel facility. His accomplishment ushered in the era of supersonic flight, it also pushed speed as a dominating factor in a combat aircraft’s design. It was at this time that Whitcomb was assigned to the Laboratory’s secret eight foot transonic wind tunnel. Within a few years of labouring there, young Whitcomb developed a reputation as an innovating thinker, a man that thought “outside the box” when it came to the aircraft’s aerodynamic characteristics. In the early part of 1950, Whitcomb submerged himself in drag aerodynamic research. He soon realized that the physics of airflow changed violently as it expands from subsonic to supersonic speeds. By late 1950, after extensive research, Whitcomb developed a theory that directly related to the wing structure design as it related to the aircraft’s overall drag profile. The wing area, he proclaimed, should be reduced in an effort to smooth the expanding airflow and mitigate the formation of shock waves that produced a high drag profile. To better explain his concept, Whitcomb studied extensively the design of artillery shells and machine guns bullets. Their smooth distribution, of what is known as the Cross Sectional Area in order to reduce the drag profile at supersonic speeds, appealed to him. Whitcomb came away from this unorthodox study with a clear vision: in order to reduce the drag profile of an aircraft, the plane needed to maintain a smooth distribution of area in the proximities of the wing structure, thus reducing the drag profile of the aircraft. The fuselage structure would have to be reduced accordingly, thus giving the airframe a “coke bottle” shape. This breakthrough idea will later be known as the Area Rule Concept.

As with many new theories, the Area Rule Concept encountered its fair amount of skepticism in aerodynamics engineering circles. As a result, Whitcomb’s research began to encounter a barrage of obstacles from colleagues and upper management, fortunately for him and the US Air Force, Adolph Busemann stepped in. Busemann, a well respected German aerodynamicist who was also working at NACA at the time, gave its full support to the newly presented area rule concept. With this impressive backing, Whitcomb was once again free to pursue his idea. He carried out a number of wind tunnel experiments during the fall of 1952 that validated his theory. Indeed, much of the collected data from these tests showed that the large drag profile encountered near Mach 1 operational speed was reduced almost 60 percent when the airframe was sufficiently reduced in the neighborhood of the wing structure. Although impressive as they were, these results were not immediately embraced by the US aircraft industries. With his research testing almost stopped by outside interference, Whitcomb again received unexpected help. This time in the form of Convair’s YF-102 supersonic fighter. The 102 design aircraft applied a delta wing configuration in an effort to reduce the plane’s drag profile at supersonic speeds. Initial testing of the completed sample plane demonstrated that although designed to fly at speeds above Mach 1, the aircraft simply could not achieve its intended threshold because the transonic drag profile was too great for even the powerful Pratt & Whitney J-57 turbojet engine to overcome. It was at this moment that Whitcomb’s concept raised to prominence. Convair’s engineers began to research ways to improve the aircraft’s drag profile. Their research, lead them directly to NACA and Whitcomb. They meet with Whitcomb and, after careful examination of the area rule concept’s wind tunnel data, the engineers modified the original 102 airframe with an area rule fuselage. The new aircraft, YF-102Amade its maiden flight on the morning of December 20th, 1954. The aircraft out-performed all expectations. The area rule concept had increased the fighter top speed by an astonishing 25 percent. The US Air Force was so impressed with new aircraft speed and characteristics, that they placed an order for 870 102As.

The success of Whitcomb’s concept also meant that it would become classified material. It remained a classified project until September 1955. Two months later, with his work in the public light, Whitcomb was awarded the prestigious Collier Trophy.

Skunk Works, Ben R. Rich & Leo Janos; Back Bay Books 1994
Alpha, Bravo, Delta Guide to the U.S. Air Force, Walter J. Boyne; Penguin Group 2003
U.S. Air Force: A Complete History, Lieutenant Colonel Dick Allan Daso USAF (Ret); The Air Force Historical Foundation 2006