Question: Lockheed Martin F-35 Lightning II development started in 1992 with the origins of the Joint Strike Fighter program and is set to culminate in full production in 2018, unlike the F-22 Raptor, is intended to be available for export, the Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft, developed for which organization?

Context paragraphs:
Boeing X-32: The Boeing X-32 was a concept demonstrator aircraft in the Joint Strike Fighter contest.  It lost to the Lockheed Martin X-35 demonstrator which was further developed into the Lockheed Martin F-35 Lightning II.

Joint Strike Fighter program: Joint Strike Fighter (JSF) is a development and acquisition program intended to replace a wide range of existing fighter, strike, and ground attack aircraft for the United States, the United Kingdom, Turkey, Italy, Canada, Australia, the Netherlands and their allies.  After a competition between the Boeing X-32 and the Lockheed Martin X-35, a final design was chosen based on the X-35.  This is the F-35 Lightning II, which will replace various tactical aircraft, including the US F-16, A-10, F/A-18A-D, AV-8B and British Harrier GR7, GR9s and Tornado GR4.  The projected average annual cost of this program is $12.5 billion with an estimated program life-cycle cost of $1.1 trillion.

Lockheed YF-22: The Lockheed/Boeing/General Dynamics YF-22 was an American single-seat, twin-engine fighter aircraft technology demonstrator designed for the United States Air Force (USAF).  The design was a finalist in the USAF's Advanced Tactical Fighter competition, and two prototypes were built for the demonstration/validation phase of the competition.  The YF-22 won the contest against the Northrop YF-23, and entered production as the Lockheed Martin F-22 Raptor.  The YF-22 has similar aerodynamic layout and configuration as the F-22, but with differences in the position and design of the cockpit, tail fins and wings, and in internal structural layout.

BAE Systems Replica: Replica was a design study for an envisioned military aircraft with stealth capabilities, developed by British defense manufacturer BAE Systems.  It was ultimately not pursued as the British government chose to proceed with involvement in the American Joint Strike Fighter program instead, which ultimately led to the Lockheed Martin F-35 Lightning II.

Lockheed Martin F-35 Lightning II development: Lockheed Martin F-35 Lightning II development started in 1992 with the origins of the Joint Strike Fighter program and is set to culminate in full production in 2018.  The X-35 first flew on 24 October 2000 and the F-35A on 15 December 2006.  The F-35 was developed to replace most US fighter jets with variants of one design common to all branches of the military.  It was developed in cooperation with a number of foreign partners, and unlike the F-22 Raptor, is intended to be available for export.  Three variants were designed: the F-35A (conventional take off and landing, CTOL), the F-35B (short-take off and vertical-landing, STOVL), and the F-35C (carrier-based CATOBAR, CV).  Despite being intended to share most of their parts to reduce costs and improve maintenance logistics, by 2017 the design commonality was only 20%.  The program received considerable criticism for cost overruns during development and for the total projected cost of the program over the lifetime of the jets.  By 2017 the program was expected over its lifetime (until 2070) to cost $406.5 billion for acquisition of the jets and $1.1 trillion for operations and maintenance.  A number of design deficiencies were alleged, such as carrying a small internal payload, inferior performance to the aircraft being replaced particularly the F-16, and the lack of safety in relying on a single engine, and flaws were noted such as vulnerability of the fuel tank to fire and the propensity for transonic roll-off (TRO or "wing drop").  The possible obsolescence of stealth technology was also criticized.

Lockheed Martin F-22 Raptor: The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF).  The result of the USAF's Advanced Tactical Fighter program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities.  The prime contractor, Lockheed Martin, built most of the F-22's airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.

Lockheed Martin X-35: The Lockheed Martin X-35 was a concept demonstrator aircraft (CDA) developed by Lockheed Martin for the Joint Strike Fighter program.  The X-35 was declared winner over the competing Boeing X-32 and a developed, armed version went on to enter production in the early 21st century as the F-35 Lightning II.

Skunk Works: Skunk Works is an official pseudonym for Lockheed Martin's Advanced Development Programs (ADP), formerly called Lockheed Advanced Development Projects.  It is responsible for a number of famous aircraft designs, including the U-2, the Lockheed SR-71 Blackbird, the Lockheed F-117 Nighthawk, Lockheed Martin F-22 Raptor, and the Lockheed Martin F-35 Lightning II, which will be used in the air forces of several countries.  Its name was taken from the moonshine factory in the comic strip "Li'l Abner".  The designation "skunk works" or "skunkworks" is widely used in business, engineering, and technical fields to describe a group within an organization given a high degree of autonomy and unhampered by bureaucracy, with the task of working on advanced or secret projects.

Lockheed Martin F-35 Lightning II: The Lockheed Martin F-35 Lightning II is a family of single-seat, single-engine, all-weather stealth multirole fighters.  The fifth-generation combat aircraft is designed to perform ground attack and air superiority missions.  It has three main models: the F-35A conventional takeoff and landing (CTOL) variant, the F-35B short take-off and vertical-landing (STOVL) variant, and the F-35C carrier-based Catapult Assisted Take-Off But Arrested Recovery (CATOBAR) variant.  On 31 July 2015, the United States Marines declared ready for deployment the first squadron of F-35B fighters after intensive testing.  On 2 August 2016, the U.S. Air Force declared its first squadron of F-35A fighters combat-ready.

Lockheed Martin F-35 Lightning II procurement: Lockheed Martin F-35 Lightning II procurement is the planned selection and purchase of the Lockheed Martin F-35 Lightning II, also known as the Joint Strike Fighter (JSF) by various countries.

Supporting paragraphs: Lockheed Martin F-35 Lightning II development Lockheed Martin F-22 Raptor
Answer: United States Air Force (USAF)