By Maj. Gen. Jasper Welch, USAF (Ret.)

During the Cold War, the US bomber force concentrated on nuclear deterrence. The inventory was large enough to permit diversion of several hundred bombers to the Korean and Vietnam wars. Even as recently as the 1991 Persian Gulf War, sixty-six heavy bombers were available to the theater commander.

The result was that since the end of World War II, Air Force planners have not had to evaluate seriously the adequacy of the bomber force for conventional, nonnuclear operations.

That situation has changed dramatically. With the abrupt end of the Cold War, the rapid decline in the political intensity of the strategic threat, pressure to reduce US military spending and forces, and formal adoption of a new, two-conflict planning scenario, officials are required to judge bomber forces primarily in terms of conventional, nonnuclear adequacy.

Against this backdrop, President Clinton early this year unveiled a Fiscal 1995 defense budget funding a total inventory of 125 bombers, of which only sixty-nine (seven B-2s, thirty-eight B-1Bs, and twenty-four B-52Hs) would be in the active-duty Air Force. This lends new urgency to the question of whether the bomber force is adequate.

This study concerns US preparations to deal with major aggression whenever time, circumstances, and hostile actions have thwarted our ability to bring sufficient general-purpose forces into place before aggression occurs. It is concerned with using bombers as the immediate reponse to halt aggression and stabilize the military situation until US general-purpose forces have time and opportunity to get to the theater, recapture territory, and enforce a favorable settlement.

In this situation, long-range bombers were paramount. However, this study is not about using bombers to replace fighters. It analyzes the quantity of munitions needed and the rate at which they must be delivered to halt aggression. It makes a case that relatively expensive standoff weapons are unaffordable for the bulk of the mission and that the cost of stealthy aircraft is offset by their ability to use relatively inexpensive precision munitions.

All evidence was that investing in new B-2 bombers would prove more cost-effective than holding on to older B-1s and B-52s. The older bombers would require expensive new avionics and standoff precision guided weapons, and the cost of those improvements would more than offset the purchase price of new B-2s. The number of B-2s plays a key role in providing effectiveness, survivability, and relatively low weapon costs in the early days of a war, when bombers are most critical to success.

The Pentagon's 1993 Bottom-Up Review (BUR) rested on a new planning scenario, postulating an international crisis in which US military forces had to cope with two major regional conflicts (MRCs), each of which was similar in scope and magnitude to the Gulf War and both of which could break out more or less simultaneously. This analysis superimposes that military requirement on five notional bomber forces, shown in Table 1.

In this chart, the entries for sixteen B-2 primary aircraft authorized (PAA) correspond to a total inventory of twenty; eighty B-1 and eighty B-52 PAA are the most that could be kept with the necessary major outlays for modifications, spares, and logistic support. Forty B-1 and B-52 PAA corresponds to the level actually planned by the Pentagon. The term "yes" under tacair means it was included in the analysis. The number of overseas bases is two--Diego Garcia and Guam (both about 3,000 nautical miles from the conflict)--or four, with two additional unspecified bases much closer (about 1,000 nm).

Here it is important to note a fundamental conclusion of the quantitative analysis: None of these notional bomber forces-even when augmented by tactical aircraft--was sufficient to meet the full range of demands imposed by the Bottom-Up Review's planning scenario. In essence, therefore, we are engaged in a quantitative analysis of the nature and degree of risk inherent in these shortfalls.

The data and analysis show that all the forces in Table 1 could temporarily halt an initial enemy invasion in the first conflict. However, all five fail to prevent timely reinforcement, reconstitution, and resumption of the invasion; to stop ballistic missile attacks from stifling the US in-theater buildup; or to finish the combat tasks of the first MRC in time for the bomber force to swing to the second MRC.

Forces with fewer B-2s would have to be equipped with several tens of billions of dollars worth of highly advanced standoff missiles so that enough of the force could survive attrition and carry out two successive campaigns.

The analysis of alternative bomber forces was undertaken against the BUR planning scenario of two unforeseen MRCs. The BUR envisioned starting dates about thirty days apart, barely sufficient time for sealift closure on the first MRC, when tactical aviation would have enough logistic support to take over.

In the first MRC, the bomber force was evaluated for its ability to halt aggression, achieve air superiority, and suppress an aggressor's power to interfere with the US in-theater buildup. The most worrisome threat was the use of ballistic missiles with chemical warheads or worse.

In the analysis, employment of bomber forces was guided by relative task urgency, a need to hold losses to twenty-five old bombers, and a requirement to minimize the cost of weapons.

All of the bombers used advanced, precision weapons throughout. This novel approach was taken because the target systems were vulnerable to precision weapons (and much less vulnerable to unguided ones), and the analysis sought to establish the minimum size of the bomber force the BUR scenario required.

The analysis left out many combat tasks, assumed good intelligence, and made scant allowance for the fog of war. Even so, the bomber forces in each MRC expended some 42,000 precision weapons-three and a half times the 17,000 PGMs used in Operation Desert Storm. Some might question that number, but use of fewer PGMs would require more bombers and time, exactly the opposite of the BUR goals. About 40,000 targets were attacked during Desert Storm.

The point of departure was the set of combat task sortie demands, ordered by relative urgency (Table 2). The target sets are consistent with the BUR planning scenario. Invading forces start on Day 1, as does the bomber force. The notation "with active missile defense" means there is a ninety-percent-effective missile defense in place on Day 1; the bomber force would not be required to find and attack mobile missile launchers. That task could consume another twenty B-2 sorties per day, if required.

The Department of Defense, in its Fiscal 1995 budget submission, announced it would not try to keep active the maximum number of older bombers. It proposed to retire some, put some in reserve units, and maintain some in training status. These actions would leave available only about half the number of bombers operating in Fiscal 1993.

Force A: The Baseline

In this analysis, the baseline force is a stylized version of the Pentagon proposal; call it Force A. Its composition (in aircraft, basing, and sortie rates) is presented in Table 4 (next page). Force A would result from the Pentagon's plan to purchase twenty B-2s, retain fifty B-52s equipped with modern PGMs, and keep fifty B-1s with enough spare engines and parts to permit full use in war.

The B-52s are generally unsuitable for attacking armor and surface-to-air missiles (SAMs), and the B-1 also is not well suited to the job of attacking these targets. Most target systems are best attacked by a combination of B-2s and older bombers. Early use of older bombers has high

• The most urgent task, "Halt invasion," is fully subscribed. The foe is halted by the end of Day 7, and the halted forces are subject to continuing attack sufficient to pin them in place throughout the first thirty days.
• "Suppress enemy air defense" receives partial coverage until Day 6. Major SAM sites are stronger in Days 1­5 than desired but are suppressed by Day 13. Reconstitution is subject to sufficient attack to limit SAM effectiveness to ten percent of initial value or less for the rest of the campaign.
• "Offensive counter-C³I" gets only partial coverage until Day 9. Only targets judged most important would be struck.
• "Offensive counterair" (OCA) comprises only harassment attacks until an intense attack sequence at Day 16. The airborne interceptor threat remains potent more than three weeks into the campaign-a bad circumstance very different from Desert Storm. Delayed completion of the OCA task was the single worst effect of bomber force inadequacy. Until intense OCA operations are almost complete, it is not feasible to start the remaining tasks without large weapon costs and heavy losses of older bombers.
• "Offensive countermissile" is delayed in initiation of its intense attack sequence until Day 25. Protection of friendly airfields and seaports would rely on defenses until Day 25. The delayed OCM effort could mean a significant delay in the airlift buildup and sealift closure. This in turn could prevent the bomber force from moving to the second MRC in time.
• "Interdict invasion route" is delayed until Day 31 for initiation of its intense attack sequence. Halted invaders could be resupplied and reinforced throughout the thirty days. The halted invasion forces could well mount a renewed drive forward in the Day 20 time frame.
• "Attack military support and reserve ground forces" is delayed until Day 34. It would be Day 44 before most of the target system could be subscribed, and then only if the reserve ground forces have not dispersed. If they have, closure would be about Day 60. Reserve forces would be available to mount a new invasion down the same route (no interdiction until Day 31 or so) or another route at any time up to six weeks into the campaign.

The fact that Force A performed so poorly and carried such high risks is disappointing, particularly because it did, after all, have some B-2s, used an array of advanced precision weapons, had good intelligence and use of off-board sensors, and retained and adequately supported eighty older bombers. However, Force A is inadequate to deal with even one MRC, let alone two nearly simultaneous MRCs.

Worse, the estimates presented here are optimistic. In any real campaign, there would be major inefficiencies and political pressures to attack targets out of sequence. Bomber losses were estimated but not fed back into projections of sortie rates. No reduction in sorties was attributed to lack of maintenance or spares. In short, the bomber force was credited with its maximum reasonable capability.

This analysis examines ways to improve the capability of the future bomber force to meet BUR requirements. The large number of weapons required, the short time available to deliver them, and the need to pursue lowest-cost solutions are driving factors in the analysis of four paths for improving the bomber force:

• Add in nonbomber airpower-naval aviation, seabased cruise missiles, and landbased fighter-bombers.
• Build up the force with more B-1 and B-52 bombers.
• Pursue a more aggressive overseas basing posture.
• Increase the inventory of newer bombers.

Force A-Plus: Add Tactical Airpower

The Air Force has made much of the synergy among fighters, cruise missiles, tactical naval air components, and bombers. If all goes well, tactical forces would begin to arrive in the theater during the first week and in substantial numbers by Day 30. These components can deliver most of the same precision guided munitions and standoff missiles that the bombers can, and they can rely on the same reconnaissance and intelligence. They also bring technical and operational attributes helpful in coping with and permanently suppressing enemy air defenses.

For a quantitative analysis of the ability of a combined bomber force and tactical airpower force to accomplish the airpower tasks at hand, it is useful to separate the tactical forces into three components:

• Stealthy F-117 fighter-bombers are able to penetrate unsuppressed enemy air defenses and deliver precision munitions. Currently, the F-117 delivers laser-guided bombs, two per sortie, that cost less than $100,000 each. These weapons require the absence of clouds between the aircraft and the target. The F-117 could be adapted to carry the all-weather Joint Direct Attack Munition (JDAM) at $100,000 per weapon. F-117s would directly add to the B-2 sorties.
• The F-15E and F-111F landbased fighter-bombers and the programmed F/A-18E/F carrier-based fighter-bombers have operational flight profiles similar in many respects to those of B-1 bombers. They are credited with the ability to deliver most of the same weapons as the B-1, in particular JDAM, Tactical Munition Dispensers (TMDs), the Joint Standoff Weapon (JSOW), and the Triservice Standoff Attack Missile (TSSAM), but not the Long-Range Cruise Missile (LRCM), for which there is no need in fighter-bomber force structure. They could deliver laser-guided bombs (weather permitting), High-Speed Antiradiation Missiles for defense suppression, and of course air-to-air weapons.
• Ship-launched long-range, precision Tomahawk Land-Attack Missiles (TLAM-Cs) are functionally equivalent to the air-launched LRCMs used extensively by the B-52 and to a lesser extent by the B-1 in Force A. They cost about as much as LRCMs, perhaps less, because the TLAM-C production line is mature and ongoing.

The major value of F-117s lay in augmenting a small B-2 force with many more opportunities than it could handle to strike deep, well defended, urgent targets. Even the small F-117 force made a big contribution to suppressing SAMs and airborne interceptors.

The major value of the F-15E, F-111F, and F/A-18E/F fighter-bombers was providing reinforcements and mass late in a campaign, after Day 20.

The TLAM-C's major value was its ability to strike time-urgent individual targets. TLAM-Cs' launch platforms are generally closer than the bomber bases to target areas. Inclusion of the TLAM-C did not produce substantial improvement in the time performance of Force A because there were plenty of B-52 and B-1 sorties to carry LRCMs and the number of LRCMs (and TLAM-Cs) used was limited by cost considerations.

Table 5 displays the quantitative results of including the nonbomber forces (Force A-plus). Their inclusion significantly shortens the time needed to complete the seven combat tasks.

Unfortunately, several serious concerns arise about Force A-plus. Estimated arrival rates of nonbomber components make no allowance for interference with or impediments to the theater buildup. In reality, such difficulties could arise from a number of causes: political opposition in the host country, sabotage, and air or missile attacks on ports and airfields, particularly with nuclear, biological, or chemical weapons.

Supporting these in-theater forces with adequate fuel, munitions, and maintenance can severely strain airlift capacity. The force would require prepositioning and/or sealift closure (about Day 30) to sustain a heavy sortie/payload rate.

These deployment surges are without any hedge toward a second MRC and involve all of the F-117s and F-15Es and the majority of the US Navy's available major combatant ships. That is, these forces would also have to be divided, with part going to the second MRC. For example, if arrival times were delayed by only fifteen days, then the total contribution by Day 30 would be only about twenty-five percent of what it would be with a Day 1 start.

Put another way, Force A-plus is internally inconsistent. The purpose of OCA and countermissile tasks is to facilitate the unhindered entry of forces into the theater, but for the nonbomber components to make a difference, they must enter before these tasks are complete.

Force A is too meager and its action too much centered on early periods of the campaign for arrival of the nonbomber forces to provide an adequate remedy. Force B: Add Older Bombers

Much of Force A's inadequacy has to do with not getting the tasks done on time. More bombers--whether old or new--can generate more sorties and increase the rate of task accomplishment.

The maximum reasonable number of older bombers (B-1s and B-52s) that could be retained in PAA status is about eighty of each, given logistic support demands. These, combined with the currently authorized production of B-2 aircraft, would result in Force B, as shown in Table 6.

The results of Force B's time performance are given in Table 5 and compared with the results for Forces A and A-plus. As can be seen from the data, doubling the number of older bombers significantly helps to wind up the campaign in time (about Day 31) for the bomber force to be available to swing to the second MRC at the nominal planning time of Day 30.

The big problem is exorbitant cost. The weapon costs for Force B for one MRC are about $42 billion--even higher than for Force A and Force A-plus. This arises because the older bombers need the more expensive standoff missiles to gain sufficient intensity of attack and maintain an acceptable loss rate. The trade-off boils down to this: Avoiding the loss of a single older bomber costs about $1 billion in weapons.

In fact, weapon costs for all three forces--A, A-plus, and B--are extremely high by historical standards. For example, total cost for air-delivered and sea-launched munitions, precision and otherwise, for Desert Storm was less than $3 billion. This much lower value stemmed from extensive use of lower-cost gravity weapons, both unguided and precision guided, and the parsimonious use of standoff precision weapons. This munitions mix was permitted when Iraq's interceptor threat collapsed early.

In Desert Storm, these lower-cost gravity precision weapons could be used in two distinct operational settings: by stealthy F-117 aircraft in areas where air defenses were strong (e.g., Baghdad) and by other fighter-bombers in areas where defenses were weak or temporarily suppressed.

Fortunately, the mismanagement and inadequacies of the Iraqi Air Force, impelled in part by the Coalition's defense-suppression campaign, provided ample opportunity for the second case. Had the Iraqi Air Force fought harder and better (e.g., as well as the North Vietnamese Air Force), then the nonstealthy fighter-bombers would have had a much more difficult and more dangerous time of it.

Thus the exploration of the second path, using more older bombers, reveals improved performance, but only at the risk of counting on the aggressor's air defense force to fail to fight or at the expense of unrealistically high weapon costs.

The analysis found that the overall effectiveness of the older bombers, on a per-sortie basis, was about sixty percent to eighty percent of the effectiveness of the B-2, depending on the particular force mix. Managing losses to fewer than twenty-five bombers would further reduce this effectiveness because the standoff weapons that would make such reductions possible are the least efficient on a per-sortie basis and the most costly.

The principal effect of enemy air defense was twofold: to limit the utility of older bombers until defenses could be suppressed and to force the use of relatively expensive standoff weapons so the older bombers could survive. Thus, in order to achieve their full potential, older bombers need an adequate B-2 force to suppress enemy air defenses.

More Modern Forces

The analysis assessed several more modern bomber forces that would provide reasonable performance in terms of winning the first MRC in time for the force to handle a second MRC (starting about Day 30), enforceable performance against a determined enemy, and performance at an affordable cost for new bombers and precision weapons.

This path entails substantial production costs, but they are more than offset by reduced production of expensive standoff precision munitions needed by the older bombers. The newer bombers, being stealthy, can use mostly precision gravity weapons rather than precision standoff missiles that cost many times more per weapon.

This path also calls for aggressive forward basing. Even from overseas bases 3,000 nm from the target area, the sortie rate is limited primarily by flight time to and from the target area. Overseas basing (temporary, only during the MRC) at 1,000 nm from the target area, for example, would provide a fifty percent sortie rate increase over basing at 3,000 nm.

In both Vietnam and Desert Storm, some bombers were relocated as far forward as was practical. Some went to Thailand and some to western Saudi Arabia, respectively. The value is increased sortie rate; the difficulty is finding available, secure base facilities.

There are costs associated with such basing structures, of course--and not only in monetary terms--but the monetary costs are modest compared to the costs of buying new weapons and aircraft.

Increased overseas basing is a powerful, cost-effective strategy for increasing the effectiveness of any bomber force. Long-range bombers do not need to be based overseas in peacetime.

Force C: More B-2s

The improvements incorporated in Force C are twofold: a modest increase in the number of B-2 bombers (rising from sixteen PAA to twenty-four PAA) and more aggressive forward basing for all bombers.

The number of older bombers is the same as for Force A. The characteristics of Force C are listed in Table 7.

The analysis shows that compared to Force A, Force C could generate about 2.2 times as many B-2 sorties per day, twenty percent fewer B-1 sorties per day, and about the same number of B-52 sorties a day.

The impact of the additional B-2 sorties is quite strong. The duration of the campaign falls from about forty-five days for Force A to about twenty-seven days for Force C (Table 8). Weapon costs for Force C are about $15 billion less for just one MRC (Table 9). Savings for weapons for two MRCs would be correspondingly greater.

There are two reasons for the strong showing. More B-2 sorties, especially early in an MRC, allow defense suppression to occur more quickly and to be performed primarily by the B-2, thus avoiding aircraft losses and costs for the more expensive standoff weapons needed by the older bombers.

The bad news: Weapon costs for Force C are still high by historical standards--about $19 billion.

It is instructive to examine trade-offs between weapon costs and aircraft losses. Precision weapon types differ in their ability to stand off from the threat of SAMs and airborne interceptors. They differ in their effectiveness against target types within the target systems characteristic of each combat task. Finally, they differ radically in cost, ranging from about $100,000 per JDAM to at least $3 million for each LRCM.

Analysis to date indicates that the trade-off is between the loss of one older bomber and an additional weapon expenditure of $1 billion. Weapon costs were established on the assumption that bomber losses would be held to about twenty-five aircraft, split roughly equally between B-1s and B-52s.

This trade-off ratio--$1 billion in standoff weapon costs per aircraft loss averted--hinges on several considerations. One is the desire to get the first-MRC combat tasks completed before the bulk of the bomber force swings to the second MRC. This time pressure encourages the US to initiate the offensive countermissile task before completing the offensive counterair task and to use older bombers to wrap up the OCA task.

Unless the older bombers were equipped with standoff weapons, this move would conflict with the need to operate at a loss rate per sortie that leaves enough bombers to fight and win the second MRC.

If further stealthy B-2s are added to the bomber force, weapon costs become markedly lower, for two reasons. First, the extra B-2s can fly sorties in heavily defended regions with less expensive weapons. Second, the addition of B-2 sorties allows the US to complete the air defense suppression tasks sooner, and older bombers could get by with fewer standoff weapons.

Forces D and E: B-2s and Bases

Two more notional bomber forces, each having more B-2 aircraft and closer bases, were evaluated for their contribution to reducing weapon cost and for shortening the duration of the air campaign.

The first, Force D, differs from Force C in two respects. It possesses thirty-two PAA B-2s--eight more than in Force C--and it positions all of them on bases within about 1,000 nm of the first MRC.

The second, Force E, differs from Force C and Force D in fairly important ways. First, it has forty PAA B-2s--sixteen more than Force C and eight more than Force D. Second, it is a pure B-2 force, with no older bombers, all of which would be retired. Like Force D, all of Force E's B-2s would be based within 1,000 nm of its targets (Table 1).

Table 8 compares the time performance of Forces C, D, and E. The data make clear that adding stealthy B-2 aircraft has a substantial impact on shortening the duration of the campaign. Even Force E, with no old bombers or tactical air forces, does a fair job, better than Force A.

Improved time performance, however, is not the whole story. Forces with more B-2s (Forces C, D, and E) actually cost less to field and employ than Forces A and B. Table 9 shows costs for three steps:

• Purchase of B-2s above the currently authorized twenty.
• Modifications to B-1s and B-52s to carry advanced PGMs.
• Purchase of munitions sufficient to win two MRCs.

When the analysis was run, one item of great interest emerged: The number of B-2 sorties produced by Force D enabled the older bombers to carry out their missions without expensive, standoff LRCMs. Thus, USAF could avoid the LRCM's steep development, production, and integration costs. It is possible that some of those costs are already sunk, and so no claim of savings is made in Table 9. Force E, with no older bombers, would not need LRCMs either. Force C, with more B-2 sorties than Force A, did not need to use LRCMs on B-1s.

The marginal cost of additional B-2s is about $600 million per inventory aircraft. Costs for modifying older bombers is $7 billion for the 160 aircraft in Force B and $4 billion for eighty bombers in the other five notional forces.

Costs for weapons are based on detailed allocations for one MRC. This cost is not doubled for the two-MRC scenario but only multiplied by 1.5. Total weapon usage for MRC 2 could well be about the same as for MRC 1, but the urgency would be less, and the force surviving MRC 1 would be somewhat richer in B-2s than the initial force, so the weapon inventory would be leaner in the more expensive types. Moreover, a larger buy would entail some economies of scale. Even so, the correct multiplier probably is higher than 1.5, and the estimate is on the low side.

The high costs of the precision weapons are driven not by the need for precision so much as the need for standoff capability to preserve the older bombers as they face modern