Factbox: Lockheed's Skunk Works behind many U.S. military aircraft

Following are some facts about the Lockheed division, whose Skunk Works name is a registered trademark, and some of the weapons it has or is developing:

* Got its start in 1943 when Kelly Johnson and his engineers designed the first fighter jet for the U.S. military in a rented circus tent next to a manufacturing plant, whose strong odors permeated the place. Under orders to keep silent about their work, even when they answered the phone, an engineer responded to a phone call one day by referencing a stinky place called the "Skonk Works" featured in the popular Li'l Abner comic strip.

* While focused mainly on aircraft, it has developed other weapons, including the Joint Air-to-Surface Standoff Missile that entered service in 2009, and nuclear fusion energy that grabbed headlines several weeks ago.

* In the 1950s, developed and built the U-2, a spy plane that flies at 80,000 feet and was fielded within eight months.

* In the 1960s, developed the SR-71 "Blackbird," a long-range spy plane that was in use from 1964 to 1998. Designed to operate at three times the speed of sound, it still holds the world record for the fastest air-breathing manned aircraft.

* After the downing of U-2 pilot Gary Powers in the Soviet Union in 1960, developed D-21, the first high altitude unmanned spy plane, which carried out four operational missions over China from 1969 to 1971.

* In the early 1980s, developed the F-117 Nighthawk, the first operational stealth fighter. Sixty-four aircraft were used in combat, beginning with the U.S. invasion of Panama in 1989. The aircraft were retired in 2008.

* In the 1990s, developed the precursors for the F-22 stealth fighter and the F-35 Joint Strike Fighter.

* Developed the RQ-170 Sentinel, a tailless, stealthy unmanned aircraft, one of which went down in Iran in December 2011. The Air Force has acknowledged the plane's existence but few details have been released.

CURRENT PROJECTS

* Teamed with Boeing Co to bid for a huge U.S. Air Force contract to build a new long-range strike bomber.

* Developing proposal for a long delayed competition to build an unmanned plane for use on U.S. Navy carriers.

* Working with Aerojet Rocketdyne, a unit of GenCorp, on a new High Speed Strike Weapon (HSSW), a hypersonic missile that could be used on future bombers and fighters.

* Testing bonds for composite materials used in aircraft, which could reduce use of fasteners that add weight and cost.

* Seeking launch customer for new hybrid airship that could be used to deliver 20 tons or more of oil and mining equipment to remote areas, for far less cost than using helicopters, and about the same as current land-based methods.

* Working on SR-72, a hypersonic, unmanned plane that would fly twice as fast as the Blackbird.

(Reporting by Andrea Shalal; Editing by Howard Goller)