Lockheed's famous Advanced Development Programmes division, better known as 'Skunk Works', celebrates its 60th anniversary today, 17 June. The Skunk Works, for many years headed by Clarence L 'Kelly' Johnson, was responsible for many of America's most secret and technologically advanced aircraft.
The organisation produced America's first genuinely operational jet fighter, in the space of only 143 days, and subsequently designed and developed the F-104 Starfighter (America's first Mach 2 fighter), the U-2 and SR-71 spyplanes, and the F-117 Stealth Fighter. These latter three types all entered operational service before their existence had been admitted!
More recently, the Skunk Works spearheaded the development of Lockheed's Advanced Tactical Fighter contender, the YF-22, now in production as the F/A-22 Raptor.