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F-35 Joint Strike Fighter (JSF) Lightning II Program


According to the DOT&E, weight growth was a significant risk for all three variants of the F-35 JSF. Aircraft weight was not a key performance parameter, but weight would impact the aircraft's ability to satisfy key performance requirements. No variant of the F-35 JSF design exceeded the weight at which key performance parameters predictions are breached. However, the STOVL design remained consistently above target weight projections. The JPO was aggressively pursuing weight reduction initiatives. Additional aircraft weight reductions were required, particularly in the case of the STOVL variant, to satisfy all key performance parameters and preserve sufficient weight reserve for post SDD block upgrades.

Weight issues and significant fundamental configuration changes forced the conclusion that the air vehicle design was insufficiently mature to satisfy all criteria for an upcoming Air System Critical Design Review. Thus, a new culture emerged that involved establishment of new indicators of progress, directed by clearly identified goals for the 2004-2005 time frame. Expect the Exceptional became much more than a Guiding Principle, it was a daily operating principle.

The F-35 JSF Program SDD schedule was aggressive and aircraft weight reduction efforts eroded a significant portion of available development time. The first flight of the US Air Force conventional takeoff and landing variant was scheduled for 2005, followed by the STOVL variant. The schedule was very challenging. The F-35 JSF Program should remain event driven with continued weight reduction efforts and design optimization before producing SDD test aircraft. The decisions the JPO faced at this point in the program were significant drivers to cost and performance limitations through the life cycle of an aircraft.

In 2004, DoD extended the JSF program schedule to address problems discovered during systems integration and the preliminary design review. Design efforts revealed significant airframe weight problems that affected the aircraft's ability to meet key performance requirements. Software development and integration also posed a significant development challenge. Program officials delayed the critical design reviews, first flights of development aircraft, and the low-rate initial production decision to allow more time to mitigate design risk and gather more knowledge before continuing to make major investments. As a result, the initial operational capability date was delayed.

As of late 2004 there was uncertainty about the number and mix of variants the services planned to purchase would also affect JSF's acquisition plans. While the Air Force had announced its intention to acquire the short takeoff and vertical landing variant, it had yet to announce when or how many it expected to buy or how this purchase would affect the quantity of the conventional takeoff and landing variant it plans to buy. In December 2004, Air Combat Command officials indicated that the Air Force was considering buying about 250 short takeoff and landing JSFs and about 1,300 conventional takeoff and landing JSFs. However, these numbers were not official.

The number and mix of JSF variants that the Navy and Marine Corps intend to purchase, and their related procurement costs, remained undetermined. However, as of late 2004 the Navy had not indicated to the developer the exact mix of the carrier and short takeoff and vertical landing variants it intended to purchase.

The cost estimate to fully develop the JSF had increased by over 80 percent from 1996 to 2004. DoD expected that by using a joint development program for the three variants instead of three separate programs, JSF development costs could be cut by about 40 percent. However, cost increases had nearly eroded all of the estimated savings. Development costs were originally estimated at $24.8 billion. By the 2001 system development decision, the costs had increased by $9.6 billion largely because of a 36-month schedule extension to allow more time to mature the mission systems and a more mature cost estimate.

The program successfully completed a DAB review on 17 June 2004. However, there continued to be some concerns with Congressional funding, as represented by the House Armed Services Committee decision to reduce funding to the program pending the IRT report and the JSF program office response.

In November 2004 Defense Department's Acting Undersecretary for Acquisition, Technology and Logistics Michael Wynne approved program changes to fix a weight problem plaguing one version of the plane. He also authorized a transition production contract for the F136 engine, made by General Electric and Rolls-Royce Group. This review was focused on the cost and schedule implications of the re-baseline effort, contractor performance to date on STOVL weight reduction, and the program's response to the IRT report on the program.

By 2004, costs increased an additional $10.4 billion to $44.8 billion. The program office cited several reasons, including efforts to achieve greater international commonality, optimize engine interchangeability, refine the estimating methodology, and extend the schedule for unexpected design work. Almost half of this increase, $4.9 billion, was a result of an approximately 18-month delay for unexpected design work caused by increased aircraft weight that degraded the aircraft's key performance capabilities.

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