Chasing Long Range Strike 1990-2009

Edit 27 Mar 11: Changed font size of post for readability in the new blog format.

Here's a little summary of the United States' steps and missteps in defining, developing and fielding a modern Long Range Strike capability since 1990. I offer it as a way to save future researchers a bit of work. I have selfish motives as well: hopefully this will let me keep a long story short in some future discussions. Enjoy.

Chasing Long Range Strike 1990-2009

This is an overview of the existing national security environment as it relates to Long Range Strike (LRS), how the LRS mission is perceived, and how the current LRS force structure and strategic direction came into being. Understanding the different factors that shape total weapon system performance, expressed in terms of effectiveness and efficiency are built on an awareness of how the LRS systems are likely to be employed and this understanding can be gained through thorough review of LRS literature.

Long-Range Strike from 1990-2007

The current LRS force structure and operational concepts are evolved constructs with roots reaching back to the late 1980's. This section highlights the pertinent events and relevant thoughts that shape current thinking on Long-Range Strike forces. These sources provide important rationale for selecting the conditions and assumptions for modeling that take place within this study.

Sole Superpower: Strength and Responsibilities

Indications that the Soviet Union and Warsaw Pact might rapidly crumble, thus changing the balance of military power, were recognized by individuals responsible for strategic planning in the late 1980s (Jaffe, 1993). After considerable internal review and consensus building at the highest levels of the Executive Branch, a new view of national defense planning emerged, colloquially known as the Base Force. The Base Force was conceived by then-Chairman of the Joint Chiefs of Staff, General Colin Powell, as the absolute lowest force structure and manning strength that the Department of Defense could retain and still carry out its superpower responsibilities in an uncertain, post-Cold War world (Jaffe, 1993).

The major impact of the Base Force on long-range strike capabilities was that it capped the bomber force end strength, and drastically cut planned acquisition of the only bomber in development, the B-2A, to only 20 aircraft. At the time of the Base Force, consideration of the bomber force end strength was framed in terms of the bomber's contribution to the Strategic Triad: the nuclear forces of the United States that also include sea-launched and land-based ballistic missiles. There was no emphasis placed on the long-range bomber's role in conventional conflict and conventional capability needs were framed in terms of fighter wing needs and reductions (Jaffe, 1993). This blindness to the long-range bomber’s conventional capability should not have been a surprise. The ‘fighter’ community’s rise in the Air Force hierarchy had eclipsed the ‘bomber’ community years before, and the Strategic Air Command’s single-minded focus on the nuclear mission was effectively an abdication of the conventional role to the Tactical Air Command (Builder, 1994, p. 186).

While the Base Force was still in formulation, some in Congress were calling for even more drastic reductions in the armed forces. By the time the Base Force was publicly announced on August 2, 1990, the day after Iraq invaded Kuwait and set in motion what would become Operation Desert Storm, the effect of Congressional defense budgets that were already forecast through fiscal year 1994 would convert General Powell's envisioned force strength floor into a defense planning ceiling (Correll, 1992). Operations Desert Shield and Desert Storm would temporarily alleviate the pressure to reduce the armed forces below Base Force levels, but after Desert Storm the pressure would return.

Desert Storm and Conventional Bomber Roles

While Operation Desert Storm was not a showcase for new bomber capabilities and roles, it served clear notice that precision-guided weapons and stealth technology would be of prime importance in future conflicts. It was seen that combining these advancements with the advantages of a heavy bomber's large payload and long-range could make future bomber conventional capabilities more important to the conduct of future wars (U.S. Air Force, 1992; Kowalski, 1993).

With this realization, the Air Combat Command and the Assistant Secretary of the Air Force for Acquisition directed the establishment of a "roadmap" to guide the Air Force in investing long-range modernization funds. The result was The Bomber Roadmap (U.S. Air Force, 1992). The roadmap's stated objective was to define the conventional bomber concept of operations, the right force structure mix of B-52, B-1B, and B-2A bombers, and the investment plan for 1994-1999 and beyond (p. 2). This roadmap, while useful in the sense that for the first time it identified the role of bombers in a post-Cold War conventional war, and quantified that capability in terms of effectiveness over the course of a Desert Storm-similar air campaign, was also severely limited in scope. The roadmap did not examine alternative force structures to determine what would be the most cost-effective strategies. Instead, it examined only how the existing force structure could be maintained and still satisfy near-term requirements within a shrinking defense budget.

Risk Assumption: Seeking the Peace Dividend

In 1992, Representative Les Aspin, Chairman of the House Armed Services Committee, proposed cuts to the military force structure and capability that were even more draconian than those planned under the Base Force concept. Representative Aspin and other leading Democrats wrongly asserted (Correll, 1992) that the Base Force concept was still mired in the Cold War mentality and that further cuts in the military could be made without increased risk. When a Democratic Administration took office in 1993, Rep. Aspin became the new Secretary of Defense, and by September of that year he had codified his views and rationale in his Report on the Bottom-Up Review (Aspin, 1993).

This review impacted the future of the long-range strike force in two ways. First, it established a force structure that was still too large for forecasted budgets (Center for Strategic and Budgetary Assessment [CSBA], 1993), thus wreaking havoc across the entire Department of Defense modernization and acquisition system by increasing competition among programs for the shrunken defense budget. Second and more directly, it used near-term and familiar, instead of most likely threats (CSBA, 1993) as a planning basis to arrive at the conclusion that no more than 184 heavy bombers (Aspin, 1993) would be required. It also described the composition of the bomber fleet that largely reflected the then-current mix, conveniently reducing the numbers of B-52s, while holding the existing fleets of B-1Bs and B-2As constant. This finding was consistent with the 1992 Bomber Roadmap, but the basic approach used in both cases drew heavy criticism (Builder, 1993).

While the review was consistent with the 1992 Bomber Roadmap, it was entirely contrary to authoritative information that Aspin had in his possession at that time. In 1992, while he was still Chairman of the House Armed Services Committee, Aspin had commissioned Major General Jasper Welch to conduct a study and author a paper titled Conventional Long-Range Bombers. General Welch is a Director Emeritus of the National Academy of Engineering and expert on many topics, including nuclear physics, advanced technology research and development, and strategic policy (U.S. Air Force, 1991). General Welch found during his research that contrary to Aspin’s assertions, the outcome of the 1991 study’s scenarios did not support then-Representative Aspin's proposed number and composition of the bomber forces, but instead supported the acquisition of 20 to 30 more B-2 bombers. The findings of the Conventional Long-Range Bombers study were not made public by Rep. Aspin at that time, but the findings were re-validated when, in 1994, General Welch updated the findings within the 1991 study for the Chairman of the Senate Armed Services Committee, Senator Sam Nunn. A summary of both studies, with scenario descriptions, was later published (Welch, 1994) which highlighted the very real need for more Long-Range Strike platforms than planned, and exposed Rep. Aspin’s attempt to squelch the findings of the 1992 study.

Congressional Concern and Executive Avoidance

In 1994, a concerned Congress tasked the DOD to determine the contribution of additional B-2 aircraft in future conventional conflicts (Tirpak, 1995) and the Heavy Bomber Force Study (HBFS) ostensibly was conducted to accomplish that task. The Heavy Bomber Force Study's assumptions were skewed so favorably to the United States’ advantage regarding warning time, basing availability, and tactical fighter pre-deployment posture, that model outputs indicated the use of additional bombers made little impact on the outcomes compared to the impact of the large force that was optimistically modeled as being already deployed and available in the theater of operations. This approach overtly diluted the effect of long-range bomber capability (Guthe, 1996). The Heavy Bomber Force Study's assumptions altered the results to the point that they indicated an additional 60-80 B-2s would have to be acquired to make a positive impact on the modeled scenarios. These assumptions enabled the study to avoid dealing with more plausible scenarios using more real-world assumptions that would have yielded different radically outcomes that would have indicated that only 10 to 20 B-2s would have made a significant positive impact on the outcomes. The conclusion of the Heavy Bomber Force Study did not address the issue of finding or excluding any benefit from acquiring new LRS capabilities but instead as several subsequent studies (CSBA, 1993) also recommended, asserted that improving the capability of the existing bomber fleet as the most cost-effective way to use the planned budget.

It should be noted at this point in the review that the forecasted weapons carriage capabilities included in the modeling for the Heavy Bomber Force Study did not include the B-2's eighty (80) 500lb, 'near-precision' Joint Direct Attack Munition (JDAM) weapons carriage option. This capability is now fielded and it had been proposed at the time of the HBFS. This development effectively gives each B-2 up to five times the lethality, in terms of aimpoints that can be struck on a single mission, compared to the baseline 2000 lb JDAM payload carriage method. That this configuration was not modeled as part of the HBFS was remarkable given that the study did advocate and cite other specific advanced weapons development proposals underway at the time that would enhance bomber lethality (Tirpak, 1995) and that indeed, the 80 500 lb JDAM effort was one of the more widely anticipated improvements for the B-2A. In addition to deficiencies in model inputs, the constructs of the HBFS’ core model itself have been found woefully deficient (Guthe, 1996).

The findings of the HBFS were largely and immediately discredited by a bipartisan group of Members of Congress (Tirpak, 1995) as well as leading military analysts. A RAND Corporation analyst, Dr. Glen Buchan, testified before a House of Representatives subcommittee in 1996 and summed up the methods of the HBFS as "Whoever framed the study, cooked the books" (Buchan, 1996, p. 208).

Not long after the release of the HBFS, the Commission on Roles and Missions (CORM) released their report. In their official report, the CORM also asserted that producing more B-2s would not be as cost-effective as buying additional precision weapons and improving existing bombers and short-range strike aircraft (CSBA, 1993). Unlike HBFS however, the Commission recommended no final decisions should be made until another study, the Heavy Bomber Industrial Base (HBIB) study, was completed.
The CORM report, like the HBFS Study before it, did not address the task it had been given by Congress. It had been chartered to examine the economic impact of losing and having to reconstitute the industrial base. Instead the commission merely iterated the industrial base could be reconstituted (Barefield, 1997) without answering the core question being asked: at what possible cost?

Shortly after the CORM released their report, it became public knowledge that it was as deficient as earlier studies, when it was revealed the CORM commission had rejected the recommendations and findings of its technical staff and instead reported findings that were unsupported by the facts in hand (Commission on Roles and Missions Staff, 1995). The CORM technical staff had conducted more than 20 different studies and found

 "the studies generally conclude that long-range bombers and the B-2 in particular, are cost-effective, and in some cases the only means of rapidly projecting survivable power" (p. 2). 

The CORM staff paper strongly advocated acquiring significant numbers of more B-2s. The staff paper was widely circulated in Congress, and was eventually made public, but the differences between the CORM report and the findings with recommendations of their technical staff were never publicly explained. This disconnect may very well have contributed to Congress’ continuing determination to keep revisiting the issue. It may have also influenced the decision of Congress to repeal budget cap limitations and to authorize additional B-2 acquisition activities as part of the 1996 Defense Authorization Act. Early in the 1996 election year, instead of applying funds for long-lead items needed to build more B-2s as intended, the President directed the acquisition funds authorized by Congress be used to only upgrade the one remaining dedicated flight-test aircraft to operational standards, bringing the total number of operational B-2s to 21 (GAO, 1996).

Approximately nine months after the CORM released its report, the Deep Attack Weapons Mix Study, Part II (DAWMS II) was released. This study examined the relative merits of weapons that could strike deep into an enemy's rear area in stopping an advancing force. The analysis included diverse weapons options including long-range artillery and missiles. The initial findings of DAWMS II supported buying more B-2s, but the scenarios were run again with changes to get different outcomes (Independent Bomber Force Review Commission [IBFRC], 1997). The second sequence of scenarios still indicated that the B-2 was an extraordinarily valuable asset (IBFRC, p. 20) during the halt-phase of an attack. But the DAWMS II findings asserted the tradeoffs required from buying more B-2s created what DAWMS II called capability gaps in other areas which were never fully described (p. 22). The primary model used to determine he DAWMS II outcome was called TACWAR. A critique (Courter & Thompson, 1996) of the DAWMS II findings noted that TACWAR seriously discounts the effects of airpower and de-emphasizes its value during the Halt Phase of a battle. This criticism was repeated in a later study (Ochmanek, Harshberger, Thaler, & Kent, 1998), which also demonstrated how future modeling could avoid the same deficiencies.

Long-Range Strike from 1997-Present

Rethinking Long-Range Strike

In 1997, the National Defense Panel (NDP) published its report Transforming Defense: National Security in the 21st Century. The purpose of the panel was to provide Congress with an alternate view (Haffa & Patton, 1998) of defense for comparison with the DOD's 1997 Quadrennial Defense Review. Haffa and Patton noted the NDP report was widely criticized for not proposing alternative force structures, but the NDP did point out that as the United States reduced its overseas presence, it would become increasingly reliant on long-range strike systems. The NDP expressed deep concern regarding the emphasis on tactical airpower modernization at the expense of long-range systems.

Also in 1997, the findings of another blue-ribbon panel, led by Chairman and former National Security Advisor Brent Scowcroft, were released. This panel, known as the Independent Bomber Force Review Commission (IBFRC), had examined the planned future of long-range strike aircraft, the importance of long-range strike to the national security, and the potential benefit of acquiring more bombers, specifically more B-2s (IBFRC, 1997). As part of their review, they dissected and critiqued many of the studies that had been conducted up to that time.

The IBFRC reached two major conclusions that were stated in the Chairman’s cover letter delivered with the IBFRC report, the first conclusion was that “long-range air power will be more important than ever in the decades ahead” and the second, “Pentagon opposition to further B-2 production is shortsighted and parochial.” The commission’s Chairman further noted in the cover letter that evidence indicated "there is a consensus across the services that long-range airpower can be abandoned in the long run” and added that it was “a view with which we strongly disagree.” The report expanded on the IBFRC’s primary conclusions, and recommended force structure changes, including acquiring "a minimum of one additional B-2 squadron" (IBFRC, 1997, p. 2) and keeping open the possibility of accelerated procurement of even more aircraft afterwards.

In October 1997, via the Defense Appropriations Act of 1998, Congress chartered one more commission to review some very specific issues related to long-range airpower and its operational employment. Within six months, The Panel to Review Long-Range Airpower released its report. In testimony before the House of Representatives’ Military Procurement Subcommittee, the panel’s Chairman stated that while the panel stopped short of recommending additional B-2s, it did recommend upgrades to existing aircraft as most 'cost-effective', as well as repeated earlier studies' recommendations to develop more advanced weapons for long-range strike aircraft. The Chairman further testified that the panel recommended the DOD create a plan to replace the existing force, stating in testimony that there was not at that time an “adequate basis” for choosing between upgraded versions of the B-2 or developing a follow-on or direct replacement, built with more advanced technologies (Panel to Review Long-Range Airpower, 1998).

Future Long-Range Strike Solution Remains Out of Reach

The Panel to Review Long-Range Airpower's call to develop a plan caused Congress in late 1998 to direct the DOD and Air Force to provide such a plan (U.S. Air Force, 1999). The product was called the U.S. Air Force White Paper on Long-Range Bombers, released in March of 1999. It was very similar to the Air Force's 1992 effort, The Bomber Roadmap, but incorporated modernization and weaponization plans that had been defined in the interim. What the new white paper did not include was a plan to replace existing systems as they became obsolete, but instead the white paper asserted that the issue did not need to be addressed until the year 2019. The assumptions made within the study, such as a viable B-52 bomber force at even the end of a proposed 80-year service life, drew heavy criticism (Thompson & Davis, 2000). Congress then directed the Air Force to update the roadmap "to include a new long-range bomber development program" (ASC, 1999, p. 2). Several studies were undertaken, including the Future Strike Aircraft (FSA) study, and even today aerospace contractors are conducting follow-on studies to the FSA effort (DOD, 2000).

In 1999, the Air Force began what appeared to be another round of studies to determine the future of long-range strike programs. The Air Force's Aeronautical Systems Center gave limited release to its in-house study, System And Operational Implications For Choosing Best Speed For Global Missions. It was designed for use by the Air Force in preparing their own personnel to "understand and evaluate the results of the contracted studies" (ASC, 1999, p. 2). The 1999 ASC study was an important first step towards ultimately establishing realistic requirements for future systems. The 1999 ASC study possessed serious deficiencies in its assumptions, internal constructs and scope, such as modeling a clearly sub-optimal subsonic planform in its analyses, but it was an important common starting point for interested parties to conduct further analyses and develop a better understanding of Long-Range Strike needs.

A lack of clear direction for fielding the next-generation LRS capability is not caused by a lack of effort. It was estimated that by 2006 that more than 20 studies had been “conducted in recent years” (Hebert, 2006, p. 26) in search of finding the best way forward for acquiring a future Long-Range Strike capability. Hebert also noted that in 2004, the Air Force Air Staff Requirements Director had stated that there had been so many Long-Range Strike studies, that “enough studying had probably been done” (p. 26) and it was time to proceed with fielding a solution. By February 2008, it was estimated that on average, one study of long-range strike requirements had been conducted every “fiscal quarter since the Cold War ended over 20 years ago” (Murch, 2008, p. 7).

While there is a dearth of publicly available and official information giving insight into the inner workings of all the later studies, there have been some official indications as to what directions these studies point towards, such as that found in the 2006 Quadrennial Defense Review (DOD, 2006):

The Air Force has set a goal of increasing its long-range strike capabilities by 50% and the penetrating component of long-range strike by a factor of five by 2025. Approximately 45% of the future long-range strike force will be unmanned. The capacity for joint air forces to conduct global conventional strikes against time-sensitive targets will also be increased. (p. 56)

This 2006 Quadrennial Defense Review (QDR) planning extract indicates that the LRS capability being sought at that time represented the force projection capability equivalent to 80 combat-coded B-2A bombers. The extract further indicates the capability sought was to be split nearly equal between manned and unmanned systems. The extract also indicates that time-critical targeting is a high priority mission for defense planners. The 2006 QDR provided additional information as to future LRS capability goals including developing “a new land-based, penetrating long-range strike capability to be fielded by 2018 while modernizing the current bomber force” (DOD, 2006, p. 46).

Also in 2006, the National Research Council Committee on Future Air Force Needs for Survivability examined the full spectrum of design and speed options. Their report acknowledged that for the near future, a subsonic strike platform is the most desirable, but also made the assertion that higher speeds should be pursued as a hedge against potential future threat environments. The 2006 Committee also recognized a need for a better basis for decision-making and thus strongly endorsed the pursuit of more capable modeling and analytical tools and techniques for future analyses. These tools and techniques were seen as needed to better understand the factors affecting survivability, and in particular the speed factor and its influences on survivability. The 2006 Committee made these recommendations based upon a consensus among panel members that determining an optimum design that adequately evaluates the speed factor and its contributions to survivability was too large and complex an issue to resolve without a significant effort beyond either the panel’s charter or ability.

Summary

Perceptions of Long-Range Strike mission requirements, including the nature of the mission itself, have evolved significantly in the last two decades: changing as the lessons learned from modern LRS implementation have taken root. The analyses used have also matured, reshaped by real-world experiences and the practical and recurring application of long-range airpower. No longer is the need for a modern LRS capability in doubt. Careful examination of the missions that LRS performs now and is expected to perform in the future has eliminated all but two concepts from consideration until well after the year 2035. Of the two remaining concepts, a subsonic platform of uncertain size is foreseen as the preferred concept for the next LRS platform to be fielded in the 2018 timeframe.

Emerging technology and its advantages are not yet well understood enough to determine if the 2035 follow-on LRS system should be a subsonic or supersonic system, with the survivability seen as the dominant unknown factor preventing a decision between the two. To close the open issues left by the previous studies and analyses surveyed in this review, a better analytical approach is needed to support decision-makers both in how well they understand LRS requirements and in how well competing LRS weapon system alternatives are able to fill those requirements.

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FURTHER READING

Arena, M.V., Younossi, O., Brancato, K., Blickstein, I., & Grammich, C.A. (2008). Why has the cost of fixed-wing aircraft risen? : A macroscopic examination of the trends in U.S. military aircraft costs over the past several decades. Santa Monica, CA: RAND.

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