The entry into service of the US F-22 Raptor in 2005 marked the unofficial arrival of the era of the fifth-generation fighter. In the coming years, as the American F-35 Lightning II and foreign competitors such as the Sukhoi T-50 and Chengdu J-20 enter the market, the fifth-generation fighter will become an important element of the global fighter market. With revolutionary advancements such as reduction of radar and infrared visibility and supersonic cruise capability, fifth-generation combat aircraft will provide an impressive boost to any nationâ€™s air force. However, according to analysis by IHS, the development and deployment of fifth-generation fighters is accompanied by various costs. Between the significant procurement price and the particular set of missions for which such aircraft are suited, nations with limited budgets for defense spending should carefully think through their options before committing to purchase these next-generation aircraft. As with most complex procurement decisions, a number of factors will define the market size and direction; in some cases, less expensive and older aircraft â€“ including retrofitted models and unmanned aerial vehicles (UAVs) â€“ may constitute a more sensible choice. Already, expectations for purchases of fifth-generations have fallen. Original projections were for around 5,000 of these advanced planes to enter service. So far, only 430 â€“ or less than one-tenth â€“ of the expected total have been committed to or paid for by various countries. While many more are expected to be purchased in the coming years, demand has a long way to go before it fulfills the original projection. Fifth-Generation Features It is useful to define the core characteristics of a fifth-generation fighter that distinguish it from predecessor generations. IHS Janeâ€™s All the Worldâ€™s Aircraft: Development & Production analysts highlight five key features that typically characterize a fifth-generation aircraft: > A reduced radar cross section, and reduced visibility to infrared sensors > Sensor fusion with scanned array radar > Linked electronics to share data with other aircraft > Supersonic cruise capability > Advanced avionics and engines These new capabilities, when combined together in one platform, provide a significant improvement in establishing and maintaining air supremacy in the early stages of a conflict. Fifth-generation aircraft are therefore considered invaluable to a leading power like the United States and its primary allies â€“ as well as other states such as Russia and China â€“ that require the ability to establish air dominance against peer competitors. According to the most recent IHS forecast, the United States alone is projected to purchase 2,616 fifth-generation aircraft; a mixture of F-22s to be used by the Air Force and F-35 variants for the Air Force, Marines and Navy. NATO allies, specifically the United Kingdom, the Netherlands, Denmark, Norway, Italy, Turkey and Canada, are forecast to purchase more than 600 of these advanced planes. Other U.S. allies such as Japan, South Korea and Australia are also on track to procure approximately 300 such planes. Rounding out the likely future purchases, Russia, China and India are expected to acquire more than 1,500 fifth-generation aircraft, intended to replace the Su-27, Su-30 and MiG-29 models, along with other indigenous aircraft. Diminished Expectations It is striking to compare these updated projections with older outlooks because the forecasts for purchases of fifth-generation aircraft have declined in recent years. Several years ago, the United States was projected to purchase around 3,200 fifth-generation aircraft, but controversies over F-35 production and an escalating unit cost have led the Obama administration to reduce these orders by more than 500 planes. Similarly, non-NATO allies at one time were projected to purchase around 350 fifth-generation aircraft, but the forecast now stands at 304, an approximate reduction of 15 percent. Fifth-Generation Expectations Fall to Earth Despite the tremendous capabilities a fifth-generation combat aircraft brings to the table, IHS assesses that the threat environment facing the majority of nations for the foreseeable future may not justify the risk and considerable expense of procuring a fifth-generation-model aircraft. There are three main reasons for this. First, the number of nations operating extensive air defense networks requiring a sophisticated capability to penetrate and establish air dominion will not significantly expand beyond existing levels. Accordingly, it is unlikely that many nations will find themselves in a position where they will be required to operate their aircraft at the high end of the operational spectrum. Second, the majority of missions most combat aircraft will fly in future exigencies will involve lower-order operational requirements, facing limited air defense networks and using existing munitions and targeting capabilities. Third, despite claims from industry, the prevailing view is that fifth-generation fighters will prove significantly more expensive to operate per hour than previously estimated. Those nations that choose to devote a significant share of their procurement budgets to fifth-generation aircraft may find that these planes have been specially designed for missions that, in most cases, they may never be required to carry out, introducing a significant opportunity cost. The Fifth Element This surplus of capability will matter less to some states than others. The United States, NATO and major non-NATO allies as well as Russia, and China, are all likely to hedge on the side of excess, even if it significantly raises their procurement costs. These leading powers cannot afford to be choosy when it comes to falling behind in the airpower race. Although the odds of a great power conflict involving significant air-to-air combat may not be high, the downside of failure to invest in the appropriate capabilities and being caught shorthanded in the early stages of a crisis are too significant for a leading power like the United States or Russia to risk. These states will proceed with purchases of fifth-generation aircraft, even though they too are not immune from cost concerns, leading to reduced order numbers when compared with older forecasts and legacy fighter fleets. To further complicate such procurement calculations, the smaller number of fifth generation fighters ordered, the higher the likely unit and operating costs. Fourth Generation Option Other, smaller states face a different proposition. Excess capabilities relative to their likely requirements in future conflicts will not be viewed as a necessary hedge, but instead as an unwarranted luxury when equally viable but lower-cost replacements are available elsewhere. In particular, fourth-generation aircraft, including F-16s and Typhoons, can serve as equally reliable stand-ins, especially when they can be purchased at significantly lower prices. When the most common operational requirements for multirole fighters, as assessed by IHS, include such missions as ISTAR, combat air patrol, and short-range strike missions, the cutting-edge capabilities offered by fifth-generation aircraft offer limited benefits over older designs, particularly when contrasted against the greater acquisition and operating costs. This particularly applies for missions pursued in the context of asymmetric warfare, an increasingly common form of conflict. Finally, in those instances where a state must turn to airpower to strike at enemy bases or troops in the face of basic air defenses, a fourth-generation aircraft â€” or an advanced UAV â€” can successfully undertake most combat operations almost as well as a fifth-generation model. This overmatch of fifth-generation capabilities against likely operational threats is likely to raise significant questions among lower-tier would-be operators, for whom this opportunity cost will be the highest. The funds devoted from limited defense budgets to the procurement and support of fifth-generation combat aircraft could instead be used to purchase ships for coastal patrols, invested instead in the necessary modernization of tanks and armored vehicles, or be plowed into enhanced training and professional development for troops. Paying for an aircraft that is rarely used for the missions that it was intended is a very expensive approach to defense planning and is unsustainable in the long run. US Heavyweight How do these disparate sets of needs and requirements impact individual forecasts for the expected procurement of fifth-generation aircraft on a nation-by-nation basis? As noted earlier, the United States will remain the heavyweight in the global market, driving the long-term upgrade and production of F-22s (all now delivered) and F-35s with a steady procurement of the latter over the next decade and beyond, ultimately totaling more than 2,500 orders of both aircraft. Crucially, this also means that, unlike the F-16 and Typhoon, the F-35 will probably remain in production into the late 2030s and beyond. By this point, few fourth-generation or forth-plus generation aircraft such as the Korean KF-X or Turkeyâ€™s TF-X or are likely to be available. Select NATO allies are expected to procure more than 600 such aircraft, which is in fact a very slight increase over original forecasts. At the same time, the Chinese are likely to invest in two modelsâ€”an approximate buy of 200 to 300 J-20 units along with more than 400 J-31 fifth-generation aircraft. The Russians, for their part, will proceed with investing in approximately 200 PAK FA and over 300 LMS aircraft that are envisaged to replace the MiG-29 fleet. Meanwhile, the Chinese J-20 (which appears to incorporate some illicit elements from Lockheed Martinâ€™s development work), may be purchased in a strength of several hundred alongside the newer J-31 aircraft that has been revealed recently. Among other states, it is notable to highlight Indiaâ€™s work on an indigenous [possibly] fifth-generation aircraft, while cooperating with Russia on the T-50. Finally, Japan is proceeding with the development of the Mitsubishi ATD-X while preparing to purchase almost 50 F-35 aircraft. History lesson It is useful to remember that expectations of the future course of military conflicts and the related utility of specific weapons systems never unfurl in the anticipated manner. During the period between World War I and World War II, many touted the continued advantages of biplanes, which offered certain advantages in climb and maneuver over monoplanes. Yet as World War II unfolded, biplanes were mostly shot out of the air and the advantages of the monoplane became quickly apparent. A similar dynamic played out during the Vietnam War, when advanced U.S. aircraft with air-to-air missile capability failed to exert significant superiority over smaller and lighter aircraft. There are a large number of such honest but erroneous assumptions about the â€˜futureâ€™ of aerial warfare that were disproved in a subsequent conflict and therefore it is likely that some of our own predictions from will be similarly found wanting. The simple fact is that we do not know the specific contours of the next aerial conflict, or which capabilities will ultimately be required. Some states, particularly major military powers, believe that they cannot afford to do anything but hedge against all risks, and will thus invest in fifth-generation aircraft. Other states, with more constrained defense budgets, will likely have to pick and choose, recognizing that the unique mission capabilities attributed to fifth-generation aircraft may prove costly and unnecessary for the actual operational requirements that they face. This delicate balancing act will define the near-term future of the fifth-generation aircraft and the extent of its penetration of the global markets. Edward Hunt is a Senior Defence Consultant at IHS Aerospace, Defense & Security, and contributes insight on aerospace and airborne defense and security matters for IHS Quarterly.