F-22 Raptor History
The Advanced Tactical Fighter (ATF) program had its origins in numerous US Air Force air combat studies carried out in the late 1970s and early 1980s, when intelligence revealed the Soviets' early flight testing of the Fulcrum and Flanker. From the observed geometry of the airframes it was clear that both types would have the vortex lift performance to challenge existing US aircraft such as the F-15 in turning dogfights. Hoever, both Soviet fighters would be handicapped by their geometry in both supersonic maneuver and low observability performance.
In 1981, the Air Force developed a requirement for an Advanced Tactical Fighter as a new air superiority fighter. It would take advantage of the new technologies in fighter design on the horizon including composite materials, lightweight alloys, advanced flight control systems, higher power propulsion systems and stealth technology. Air Force leaders believed these new technologies would make aircraft like the F-15 and F-16 obsolete by the early 21st century.
The requirement for the F-22 was identified through the process described in Air Force Instruction (AFI) 10-601, Mission Needs and Operational Requirements Document and Procedures. During the early 1980s, the Air Force assessed its tactical capabilities against projected threats and determined that a mission deficiency would exist in the near future that could jeopardize the ability of the United States to ensure that its forces had the freedom of action to conduct operations against opposing forces. The Advanced Tactical Fighter Statement of Operational Need (November 1984) detailed this need, and Congressional funding and approval were received in 1985.
The ATF was to be the successor to the F-15, a long range air superiority fighter with the performance to kill any other tactical aircraft and the operating radius to threaten targets deep inside the USSR while flying from bases in Western Europe. This was to be achieved by the use of a highly integrated airframe/systems/propulsion design exploiting advanced aerodynamics, engines and stealth technology, the latter to delay an opponent's initial firing opportunity for as long as possible, and thus capitalise on the large Radar Cross section (RCS) of the Fulcrum and Flanker.
Modern weapon systems have traditionally contained many more specifications and greater detailed Statements of Work [SOW] than those of the past. Contrast the Army Signal Corps SOW for the Wright Brothers' heavier-than-air flying machine in 1908 to the Air Force SOW for the Advanced Tactical Fighter in 1986. Requirements in the 1908 SOW (e.g., be easily taken apart for transport in Army wagons and be capable of being reassembled for operation in an hour, carry 350 pounds for 125 miles, and maintain 40 miles per hours in still air) and other contract conditions were specified on one page. The requirements section in the 1986 SOW for the Air Force Advanced Tactical Fighter was 85 pages long with 300 paragraphs of requirements.
Subsequent to studies, an RFP was issued in July 1986. In October 1986, the Phase I Demonstration/Validation (Dem/Val) program was initiated, and the F-22's operational requirements, or Key Performance Parameters, were established. These parameters were documented in the System Operational Requirements document in 1987 and supported a Milestone I decision. Two contractor teams, Northrop/McDonnell-Douglas and Lockheed/Boeing/General Dynamics were selected in October 1986 for the initial 50 month demonstration/validation phase flyoff between the YF-22 and YF-23, the original designations of the F/A-22. The rollout of the prototypes was initially scheduled for mid 1989, but ongoing slippages delayed this. Both ATF prototypes were approximately 10% larger than the F-15 and both carry approximately twice the internal fuel of an F-15C, while both have about 50% more wing area at about 30% greater combat weight. As such both aircraft clearly illustrate the long range air superiority mission which was originally envisaged for the aircraft, penetrating deep into Soviet airspace to destroy air defence aircraft and to disrupt Soviet offensive air operations.
The F-22 team conducted a 54-month demonstration/ validation (dem/val) program. The effort involved the design, construction and flight testing of two YF-22 prototype aircraft. Two prototype engines, the Pratt & Whitney YF119 and General Electric YF120, also were developed and tested during the program. The dem/val program was completed in December 1990. Much of that work was performed at Boeing in Seattle, Lockheed (now known as Lockheed Martin) facilities in Burbank, California, and at General Dynamics' Fort Worth, Texas, facilities (now known as Lockheed Martin Tactical Aircraft Systems). The prototypes were assembled in Lockheed's Palmdale, California, facility and made their maiden flight from there. Since that time Lockheed's program management and aircraft assembly operations have moved to Marietta, Georgia, for the EMD and production phases.
The System Operational Requirements document were updated on 1 March 1991. During the same time, the Advanced Tactical Fighter Full-Scale Development Environmental Assessment was prepared. Full-Scale Development has been subsequently redesignated as Engineering and Manufacturing Development (EMD).
In August 1991, the YF-22 was declared the winner. The F-22 passed milestone II in 1991. The System Operational Requirements document was validated by the Air Force and the Department of Defense (DoD) during the 1991 Advanced Tactical Fighter (ATF) Milestone II review. At that time, the Air Force planned to acquire 648 F-22 operational aircraft at a cost of $86.6 billion. After the Bottom Up Review, completed by DoD in September 1993, the planned quantity of F-22s was reduced to 442 at an estimated cost of $71.6 billion.
In August 1991, two contracts totaling $10.91 billion ($9.55 billion for the airframe and $1.36 billion for engines) were awarded for Engineering and Manufacturing Development (EMD) of the F-22 and F119 to the then Lockheed/Boeing/General Dynamics team and Pratt & Whitney. Contract changes, including three Congressional budget cuts and subsequent rephases of the schedule since had elevated the contract values to a total of $18.6 billion. Under terms of the contract, the F-22 team would complete the design of the aircraft, produce production tooling for the program, and build and test nine flightworthy and two ground-test aircraft.
As the result of a FY93 funding shortfall due to cost increases and a Congressional budget cut, and two additional budget cuts in FY94 and FY95, the F-22 EMD program schedule was rephased in early 1993 and again in mid 1994. The F-22 program was rescheduled due to funding shortages. The rescheduling resulted in an 1l-month delay in the first flight date (to 59 months from E&MD start, twice as long as average recent experience) and an 18-month delay in the planned Milestone III date. These delays were not be misconstrued as further reducing risks since resource shortages had not allowed known technical risks to be attacked as soon and as aggressively as they might have been. An important exception was in the area of software and processing, where the contractor has maintained the original schedule and staffing plans.
The Defense Science Board Task Force on Aircraft Assessment was convened to respond to direction received from Congress in the National Defense Authorization Act for FY93 (Public Law 102-484). The Task Force first met on 21 January 1993. OSD requested the report be provided on 25 February 1993. During this time the Task Force met seven times.
The Task Force viewed the area of highest technical risk in the F-22 program as the integrated avionics and its associated integration software. Other risk areas included low-observable materials and structures, engine durability, and weight and drag management. The Task Force believed that the critical risk areas had been clearly identified, were being addressed to the extent commensurate with their importance and were being adequately managed. Particular note was taken of the extensive avionics flying testbed program. The compounding of the technical challenges, potential adverse economic factors, and cost uncertainties, could pose serious risk to the program. The F-22 program was rescheduled in late 1992 for funding and other reasons. The first flight date was delayed 11 months.
The F-22 incorporated revolutionary advances in airframe, low-observable technology, maneuverability, engines, materials, and integrated avionics systems.
The F-22 E&MD program experienced difficulties typical of aircraft programs in E&MD. Airframe design refinements had negative impacts on weight and drag. In particular, "bumps" resulting from the repackaging of internal systems caused increased drag. However, there was still margin in currently estimated levels of weight and drag to meet the System Operational Requirement Document (SORD) and Approved Program Baseline (APB) performance goals. Lockheed Aircraft identified areas for additional fuel tankage as a hedge against possible increases in weight, drag and specific fuel consumption (SFC) at mission design points.
The F119 engine began ground testing in December 1992. Difficulties revealed in ground testing included performance shortfalls in the fan and turbine and high stresses in the second fan blade and low-pressure turbine blade. Lower-than-expected fan efficiency presented a risk in meeting subsonic SFC specifications. However, with identified planned improvements for several components, SFC was predicted to surpass specifications. Overall engine weight was below specification, but the nozzle was above its allocation. Also, because of the nozzle's aft location, this was noted as having potential implications for the aircraft's center of gravity (CG). Concern was expressed that the new materials technology associated with the nozzle may present durability problems.
The highest technical risk in the F-22 program stemmed from a new concept in aircraft avionics, a highly integrated avionics functionality expected to reduce pilot workload substantially and provide the pilot with unprecedented situation awareness. During the Dem/Val phase of this program, algorithms for data fusion and software development were examined, and a flying testbed was used to reduce the risk for some elements of the avionics. During E&MD a new computer processor was designed, considerable software was written and ground tested, and avionics system and software integration were accomplished on the flying testbed before integration into the F-22 aircraft. The newness of the concept (compared to the avionics architecture of what was flying at that time) and the extensiveness of the integration represented a technical risk that warranted continuing aggressive management attention.
Low-observable and other new composite materials presented another area of risk, as was the case in most advanced low observable aircraft. The radar radome, which was part of the aircraft's integrated forebody, required relatively risky materials/manufacturing concepts that delt with the offsetting requirements of radar detection range, aerodynamic performance, and radar crosssection.
The Preliminary Design Review (PDR), a major program milestone, was reached in the spring of 1993. Critical Design Review (CDR), the final major milestone before assembly began, was completed in 1995. The purpose of the review was to ensure that all performance and functional requirements had been incorporated into the design of the F-22, in order to verify that required development tasks involving detailed design had been completed and to confirm the program met all necessary criteria to proceed into the next development phase, fabrication and assembly.
Fabrication of the first part for the first flyable F-22 began on 8 December 1993, at Boeing's facilities in Kent, Washington. The first part was a forward boom keelson panel made of titanium. Assembly operations of the first flyable F-22 began on schedule at Lockheed Martin Tactical Aircraft Systems in June 1995. Boeing began assembly of the aft fuselage in October 1995, and assembly of the wings in January 1996. Assembly of forward fuselage began in Marietta in November 1995. LMTAS completed assembly of the mid fuselage in August 1996, and after shipment to Marietta mate operations began. The aft fuselage arrived in Marietta in mid-October 1996, and the wings in November. The first two Pratt & Whitney F119 engines were installed in the first aircraft in December 1996.
The FY96 budget request was reduced by the Department of Defense, which necessitated a third rephase of the F-22 program.
A Joint Estimate Team was chartered in June 1996 to review the F-22 program cost and schedule. JET concluded that the F-22 engineering and manufacturing development program would require additional time and funding to reduce risk before the F-22 enters production. JET estimated that the development cost would increase by about $1.45 billion. Also, JET concluded that F-22 production cost could grow by about $13 billion (from $48 billion to $61 billion) unless offset by various cost avoidance actions. As a result of the JET review the program was restructured, requiring an additional $2.2 billion be added to the EMD budget and 12 months be added to the schedule to ensure the achievement of a producible, affordable design prior to entering production. The program restructure allowed sourcing within F-22 program funds by deleting the three pre-production aircraft and slowing the production ramp. Potential for cost growth in production was contained within current budget estimate through cost reduction initiatives formalized in a government/industry memorandum of agreement. The Defense Acquisition Board principals reviewed the restructured program strategy and on 11 February 1997 the Defense Acquisition Executive issued an Acquisition Defense Memorandum approving the strategy.
The Quadrennial Defense Review Report, which was released in mid-May 1997, reduced the F-22 overall production quantity from 438 to 339, slowed the Low Rate Initial Production ramp from 70 to 58, and reduced the maximum production rate from 48 to 36 aircraft per year.
The F-22 EMD program marked a successful first flight on 7 September 1997. After its first flight, Aircraft 4001 was brought back to assembly line in the main production building at Lockheed Martin Aeronautical Systems where it underwent minor structural modifications that were required to achieve planned flight test envelope capability. These modifications were completed in November 1997. The aircraft, the first of nine flyable engineering and manufacturing development (EMD) F-22s to be built by the Lockheed Martin-Boeing-Pratt & Whitney contractor team, was delivered to the Air Force Flight Test Center at Edwards AFB, CA, on 5 February 1998 in the cargo hold of a Lockheed Martin C-5 transport.
Verification testing of the F-22's radar cross section (RCS) signature was performed using a full-scale replica of the F-22, built to production tolerances, that incorporating numerous production components and materials, including all major signature contributors. According to program officials, the model was the most detailed signature model ever built. The F-22 RCS full-scale pole model tests were essential to confirm both modeling data and component level characterization of the F-22's low observable design. These tests would confirm the operational signature of the F-22's design and give the team confidence in the fighter's low-observable features. F-22 RCS testing was performed at the Helendale Measurement Facility, a state-of-the-art RCS measurement facility operated by Lockheed Martin. During the initial phases of testing, the model was mounted upside-down, so engineers could get a good look at the bottom of the aircraft. Later, the model was flipped over so that the top of the aircraft could be examined. Additionally, near-field RCS measurements (i. e. close to the aircraft) were taken for correlation with data taken in the F-22 indoor RCS measurement facility at Lockheed Martin Aeronautical Systems in Marietta, Georgia.
Each calendar year, the Defense Department, along with the Air Force, establishes a set of specific goals that the F-22 program must meet to move to its next phase. Nine such DoD program criteria were established for 1999, including supercruise, flight at Mach 1.5 without fuel-guzzling afterburners, flight in excess of 60 degrees angle of attack, and the initial radar cross-section full-scale pole model testing.
In March 1999 the General Accounting Office (subsequently renamed the Government Accountability Office) reported that the F-22 program was projecting cost increases of $667 million in the aircraft's engineering, manufacturing and development program. At that time, the F-22 program team proposed $660 million in cost savings initiatives. The Air Force undertook several initiatives to control costs, including scrubbing development costs, using management reserve funding and deferring non-essential combat capability By the end of 1999, the program had realized $860 million in savings from those initiatives.
By mid-1999 the ambitious technical goals of the F-22, which included a series of new production processes as well as the most advanced avionics and electronics ever fielded on a US aircraft, had led to a series of delays in the F-22 development program. Juxtaposed with the Air Force's desired fielding schedule, this led to a program whose history had been marked by continual cost growth and whose acquisition profile would, even if examined in isolation, raised serious questions about the overall affordability and feasibility of the program.
The F-22 experienced several technical problems including: manufacturing problems with titanium castings, delamination of longerons, structural weaknesses in aft fuselage, anomalies in brakes, inertial reference system and environmental control system, nagging fuel leaks, problems with engine low pressure turbine blades, high pressure turbine blades, and engine combustors, and problems with excessive engine vibration. The Air Force reported that as of mid-1997 there were 97 issues limiting aircraft operations and 68 issues limiting ground maintenance.
Based on Air Force acquisition reports, the F-22, even without further cost growth, was projected to cost three times as much as the aircraft it replaced (the F-15). The unit cost of the six F-22's proposed to be procured with FY00 funds was $300 million per plane compared to a $55 million per plane cost for the F-15. To finance such an expensive program, DoD's modernization plan requires unprecedented levels of spending on tactical aircraft over the next 20 years. In fact, DoD's tactical aircraft modernization plan required twice the historical percentage of procurement dollars to buy roughly half the number of aircraft.
At the end of the Cold War, the House Appropriations Committee recommended termination of the F-22 (then called the Advanced Tactical Fighter) based in part on concerns over cost growth and unrealistic budgeting. Then, the Air Force told the Committee that F-22 development would cost $14 billion, a $900 million increase from the estimate provided six months earlier. Since then, the program experienced a decade of cost growth with the 1999 estimate for F-22 development exceeding $23 billion. In the first six months of 1999, the development cost increased another $700 million and the production cost of just the first 6 aircraft increased $300 million.
The F-22 program was budgeted for more than $23 billion from 2000 to 2006, and had a ''total cost to complete'' of $40 billion assuming the Air Force's then current schedule, cost estimates, and inventory objective of 339 remained static. Independent cost estimates developed within the Pentagon, the Congressional Budget Office, and the General Accounting Office all indicated that the Air Force production cost estimates were excessively optimistic. For example, the Cost Analysis Improvement Group within the Office of the Secretary of Defense, responsible for developing independent cost estimates for the Secretary, believed the F-22's total production costs were understated by at least $9 billion.
By mid-1999 the program had completed only five percent of the required testing. The advanced sensors and avionics (perhaps the highest risk elements of the program) had not been tested on the F-22 at all. Yet the FY00 budget proposed production funding for six aircraft. Overall, the Air Force's acquisition strategy required the purchase of over $13 billion worth of aircraft before completion of basic operational testing. The unit cost of these initial aircraft increased 40 percent between 1997 and 1999.
In the FY00 defense budget that began 1 October 1999, the Congress refused to approve a $1.8 billion Air Force request to buy the first six aircraft in the start of the 339-jet production program. Instead, the Congress mandated new testing milestones and approved a complicated package that allowed the Air Force to spend as much as $1.18 billion: $634 million to buy six more test aircraft, $275 million as a down-payment on the next batch of 10 aircraft, and, $300 million for liability coverage in case the program was canceled.
On 30 December 1999 the Air Force awarded contracts totaling more than $1.5 billion to Lockheed Martin Aeronautical Systems, Marietta, Georgia, and Pratt & Whitney, West Palm Beach, Florida, to build six F-22 Raptor production-representative test vehicles. The contract awards to the F-22's airframe manufacturer, Lockheed Martin, were valued at slightly more than $1.3 billion. These follow an earlier $195.5 million, advance buy contract to the company. A separate contract award of $180 million to Pratt & Whitney funded two F-119 engines for each of the six aircraft, for a total of 12 engines. The first of the F-22 PRTV aircraft was scheduled for delivery to the Air Force by March 2002 for force development evaluation activities at Nellis Air Force Base, Nevada. In a related effort the same day, the Air Force awarded the same two manufacturers separate, additional F-22 contracts totaling $277.1 million, to support the Lot 1 Advance Buy of l0 production F-22s. Lockheed Martin received $275.4 million, while Pratt & Whitney received $1.7 million. According to program officials, these contracts focused on activities preliminary to building actual aircraft, such as buying components, vendor start-up and other procurement costs.
The decision to enter low-rate initial production (LRIP) rested with the Defense Acquisition Board (DAB) chaired by the defense undersecretary for acquisition and technology. During 2000 the F-22 program faced the challenging task of completing 11 DAB criteria needed to satisfy an LRIP decision by 31 December 2000. Despite several delays, by the end of the year the program had completed eight of the criteria, to include: critical design review for the avionics Block 3.1 software, air vehicle final production readiness review, aircraft 4008 mate of the fuselage, wing and empennage, and the first half engine qualification test. Also completed were flight testing high angle of attack with weapons bay doors open, demonstrating missile separation for the AIM-9 and AIM-120, initiating fatigue testing, and completing static structural tests.
The Defense Acquisition Board (DAB) criteria for Initial Service Release of the Raptor's engine was to complete one half of 4,330 Total Accumulated Cycle (TAC) tests by December 2000. A TAC was a measure that takes the jet engine from one power setting to another and then back to the original setting. The Air Force and Pratt & Whitney team at the Air Force's Arnold Engineering Development Center (AEDC), Arnold Air Force Base, Tennessee completed 2,168 TACs on 31 October 2000.
On 5 January 2001 the program passed another milestone, with the first flight of an F-22 Raptor equipped with combat-capable avionics with Block 3.0 software. The remaining two criteria to be completed included first flight of Raptor 4006 and initiating radar cross-section flight testing. On 5 February 2001 Air Force officials announced the completion of the final two requirements, first flight of Raptor 4006 and initiating radar cross section testing, which cleared the way for an F-22 production decision.
Technical issues were not the biggest challenge for the F-22 program, affordability was and continued to be the primary factor. Air Force cost estimates indicated the program could exceed the Congressional cost cap of $37.6 billion for production of 333 aircraft if steps to reduce costs were not taken. There were three key elements in cost containment. First, production cost reduction goals for future lots were established. Second, an incentive program was developed that returned a portion of the cost savings to the primes and suppliers. Third, an investment pool was created to implement cost savings initiatives.
Establishing affordability goals for future lots was the first step. For production Lot 2, a group of major suppliers would be involved in goal-setting using the Lot 1 negotiated values as a starting point. In parallel with setting those goals, a partnership agreement between the government, primes, and suppliers would be established to ensure the parties agree to the concept of operations. Expansion to the rest of the supplier base was planned to occur by Lot 3. For suppliers, four levels of incentives would be established related to cost performance. Over the 2001-2005 period, $475 million in investment funds would be made available by the Air Force to implement affordability initiatives. The investment includes $260 million previously planned for affordability improvements and $215 million made available by rephasing Low Rate Initial Production aircraft lot quantities. The rephasing was not expected to impact the F-22 achieving initial operational capability in 2005.
The F-22 program received temporary "bridge" funding from the government in early January 2001 to keep development and production operations going until a new Defense Acquisition Board (DAB) decision to put the F-22 into low-rate initial production (LRIP) was reached. The purpose of the bridge funding was to keep the supplier base intact and the program on schedule. The $353 million bridge funding came from the $2.1 billion previously authorized and appropriated by Congress in FY01 for Lot 1 production. Of that $353 million, the Lockheed Martin-Boeing airframe team received $304 million, with the balance funding Pratt & Whitney's F119 engine operations, as well as other government tasks.
Assembly of the first operational F-22 Raptor fighter began in March 2001. Assembly of the mid-fuselage for Raptor 4018, as this F-22 was designated, would take approximately 11 months. Once completed, it was delivered to Lockheed Martin Aeronautics' Marietta, Georgia, facility, where the aircraft's forward fuselage, wings, aft fuselage, and vertical and horizontal tails were attached and its F119 engines was installed.
The F-22A Raptor achieved Initial Operational Capability [IOC] on 15 December 2005. Reaching the IOC milestone culminated a collaborative effort between various Air Force organizations and the service's industry partners over 25 years. The road to IOC included the F-22A System Program Office turning Air Force requirements into a successful acquisition program, developmental flight test and evaluation, simulation and ground testing at Edwards AFB, California, and Eglin AFB, Florida, engine testing at Arnold AFB, Tennessee, missile testing at Holloman AFB, New Mexico, and over the Pacific Test Range tactics development at Nellis AFB, Nevada, pilot and maintenance training at Tyndall AFB, Florida, and deployability at Langley AFB, Virginia. The first combat-ready Raptors were assigned to the 27th Fighter Squadron, one of three squadrons assigned to the 1st Fighter Wing. The 27th FS combat deployment capability with the F-22A is a 12-ship deployable package designed to execute air-to-air and air-to-ground missions.
On 15 May 2012, George Little, acting assistant secretary of defense for public affairs, said that Secretary of Defense Leon Panetta had ordered the Air Force to take additional steps to mitigate risks to F-22 pilots and expedite the installation of an automatic backup oxygen system in all of the planes. In addition, effective immediately, all F-22 flights were to remain near potential landing locations to enable quick recovery and landing should a pilot encounter unanticipated physiological conditions during flight. Beginning in 2008, F-22 pilots began experiencing hypoxia-like symptoms when flying the aircraft. Subsequent attempts by the primary contractor Lockheed-Martin to fix to the problem were unsuccessful, and a supplementary filter reportedly introduced carbon particles into the oxygen system. The core issue with the aircraft's oxygen system remained known at that time, but continued to be investigated. A fatal crash in 2010 was ruled as pilot error, but the issue with the aircraft's oxygen system caused the Air Force to ground the F-22 fleet twice in 2011. At least 2 pilots have since refused to fly the aircraft and have been granted whistleblower protection against overt retribution from the Air Force.
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