Order Code RS20915
Updated March 25, 2005
CRS Report for Congress
Received through the CRS Web
Strategic Airlift Modernization: Background,
Issues and Options
Christopher Bolkcom
Analyst in National Defense
Foreign Affairs, Defense, and Trade Division
Summary
There is a growing consensus that the U.S. strategic airlift fleet provides an
increasingly important military capability, and is increasingly stressed. The Department
of Defense’s (DOD) latest mobility study points to a shortfall in current and projected
airlift capability. Several options have been suggested to address this reported shortfall.
This report will be updated as events warrant.
Background
The ability to project military power over great distances is a central tenet of the U.S.
national military strategy and the massive military buildup before Operation Desert Storm
(the 1991 war with Iraq) highlighted the value of strategic airlift. U.S. aircraft moved
over 500,000 troops and 543,548 tons of cargo.1 Strategic airlift has also played a key
role in recent conflicts. On April 10, 2003, the U.S. Transportation Command reported
that it had exceeded its Operation Desert Storm airlift operations by flying 16,213
missions for the most recent war in Iraq, Operation Iraqi Freedom (OIF). Air mobility
sorties made up the majority of the 28,500 total sorties that have been flown during OIF,2
and C-17s executed a much publicized airdrop of the 173rd Airborne Brigade into northern
Iraq. Other transportation modes, such as sealift, can deploy troops and equipment. The
strongest argument for using airlift instead of other modes is speed.
Despite its importance, today’s U.S. strategic airlift system is under stress. Over the
past 10 years, the United States has reduced its Cold War infrastructure and closed two-
thirds of its forward bases. Therefore, to maintain the same level of global engagement,
U.S. forces must deploy more frequently and over greater distances. Even prior to the
September 11, 2001 terrorist attacks and resulting conflicts, the Air Force estimated that
it deployed four times more frequently than when it enjoyed the larger, Cold War
1
Gulf War Air Power Survey, vol. V, (Washington: GPO, 1993), p. 76.
2 Chuck Roberts, “C-130 Crews Keep The Supplies Coming,”
Air Force News, Apr. 16, 2003.
Congressional Research Service ˜
The Library of Congress
CRS-2
infrastructure.3 General Charles T. Robertson, former Commanding General of the U.S.
Transportation Command, testified that “Bottom line: This nation’s number one defense
transportation shortfall is its ailing and numerically inadequate strategic airlift fleet.”4
Strategic Airlift Platforms. The U.S. strategic airlift force includes the C-5
Galaxy, the C-17 Globemaster, and the C-141B Starlifter. Aerial refueling aircraft also
contribute to airlift.5 The
C-5, made by Lockheed Martin, is typified by its payload and
range. One of the largest aircraft in the world, the C-5 can carry 160,000 lbs of cargo up
to 3,730 nautical miles and has a maximum payload of 291,000 lbs. The C-5 can carry
large and irregularly shaped cargo, such as the Army’s 74-ton mobile scissors bridge, that
no other U.S. aircraft can hold. Both the nose and aft ends of the C-5 open, facilitating
rapid loading and off-loading. The C-5 has been plagued by reliability problems; its
mission capable rate for 2000 was 58 percent. The Air Force operates 126 C-5s in the
active, reserve and national guard forces.6 The C-5A was first deployed in 1969, and the
C-5B, which features upgraded wings and avionics, was first introduced in 1980.
The
C-141B, made by Lockheed Martin, can carry 68,000 lbs of cargo 2,270 nautical
miles. The C-141B is also used to carry out the U.S. Army’s airdrop mission. As of June
2004, only 30 C-141Bs remain in the active inventory. Current plans call for these
aircraft to be phased out by 2006.
The
C-17, made by Boeing, is DOD’s most modern strategic airlifter. Because it can
use short and unfinished runways and has high maneuverability on the ground, the C-17
can operate in environments traditionally confined to smaller airlifters like the C-130
Hercules. Thus, the C-17 can deliver its payload from the United States directly to
forward bases near the battle. Like the C-5, the C-17 can carry outsize and oversize cargo
like helicopters and missile launchers. Its maximum payload is 160,000 lbs which it can
carry up to 2,400 nautical miles. Current plans call for the acquisition of 180 aircraft. Air
Force officials have said, however, that they require at least 222 C-17s to meet existing
requirements.7
Strategic Airlift Requirements
In March 2004, DOD announced that it would initiate the “Mobility Capabilities
Study” a new assessment of strategic military airlift requirements. A new study is needed,
officials say, to take into account the changing, “post-9-11” security environment, and the
3 Maj. Gen. Howie Chandler,
Basic Air Force Structure and Expeditionary Aerospace Force
(EAF) Operations, Briefing to U.S. Congressional Air Force Caucus, Mar. 23, 2001, Bolling
AFB.
4 Statement of General Charles T. Robertson Jr., USAF, Commander-in-Chief United States
Transportation Command, in U.S. Congress, Senate Committee on Armed Services,
Subcommittee on Seapower,
Strategic Airlift and Sealift Imperatives for the 21st Century, 107th
Cong., 1st sess., Apr. 26, 2001, p. 21.
5 For more on the C-17, see CRS Report RL30685,
Military Airlift: The C-17Aircraft Program.
6 U.S. Air Force Fact Sheet.
C-5 GALAXY. [http://www.af.mil/factsheets/]
7 Amy Butler, “Lawmakers Accuse Air Force of Financial ‘Slight of Hand’ In C-17 Contract,”
Defense Daily, June 15, 2004.
CRS-3
air mobility lessons learned from Operations Enduring Freedom (Afghanistan) and Iraqi
Freedom. The Mobility Capabilities Study should be published in April 2005.
In March 2001, the Air Force’s Air Mobility Command (AMC) released an
unclassified summary of its Mobility Requirements Study 05 (MRS-05). This is the first
comprehensive mobility study in five years, and designed to identify U.S. airlift needs up
to the year 2005. MRS-05’s principal finding is that the goal set by the last mobility
study, for an airlift fleet capable of moving 49.7 million ton miles per day (MTM/D) of
personnel and cargo, is inadequate to meet the current national military strategy. MRS-05
recommends an airlift fleet capable of 54.5 MTM/D. It says that DOD needs 51.1
MTM/D of lift capacity to fight and win two nearly simultaneous major theater wars
(MTWs). Three additional missions are of the highest priority, and require an additional
3.4 MTM/D of lift capability: conducting special operations, deploying theater missile
defenses, and supporting non-combat theaters. DOD’s current strategic airlift capability
is approximately 44.7 MTM/D, which is 5.0 MTM/D short of the 1995 goal, and nearly
10 MTM/D short of the MRS-05 goal.
AMC identified a number of missions and scenarios that would require up to 67
MTM/D of airlift capability. However, it recommended, and the Chairman of the Joint
Chiefs of Staff and the Service Chiefs agreed, that 54.5 was the “minimum-moderate risk
capability.”
Some Options
At least five approaches have been suggested that might be pursued to address
DOD’s airlift capabilities and needs. Each option has strengths and weaknesses. These
options are not mutually exclusive, and some might be pursued concurrently.
Option 1: Modernize C-5s and Purchase Additional C-17s. The Air Force
is considering the purchase of additional C-17s and is also pursuing the extension of the
C-5’s life through engine and avionics modernization programs. At issue is how many
more C-17s to purchase and how many C-5s to upgrade. The current Air Force plan is
to upgrade all C-5s. Some have argued that only the C-5Bs should be upgraded and the
C-5As should be retired.
Modernize C-5 Fleet
Buy More C-17s
Cost Estimate8
$91M each
$334.2M each
Production Rate
12 aircraft/ year
approx 12 aircraft/year
Aircraft Life Remaining
29,000 hours
30,000 hours
Maximum Load
291,000 lbs
160,000 lbs
Mission Capable Rate
approx 75%
78.6 - 85.9%
Direct Delivery Capability
No
Yes
8
Selected Acquisition Report (SAR) Summary Tables, Department of Defense OUSD(AT&L)
Apr. 2, 2004. As of Date: December 31, 2003. Total acquisition cost estimate. Assumes 180
aircraft buy for C-17 and 112 aircraft modifications for C-5.
CRS-4
Cost is an important factor to consider when choosing between these three
alternatives, as is performance. The table above summarizes some of the factors to be
weighed. Five additional factors merit discussion. First, the C-17 is the only U.S.
strategic airlifter still in production. Purchasing additional aircraft beyond what is
currently programmed would extend the production line’s life, and may offer industrial
base benefits. Second, purchasing additional C-17s and allowing the C-5 fleet to atrophy
would lead to a homogeneous fleet. Some voice concern that a fleet composed entirely
of one model of aircraft is less robust than a fleet composed of two types of aircraft. If
one type of aircraft is grounded, the other can still fly. Others argue that homogeneous
fleets offer potentially significant savings in operations and maintenance costs, and that
the U.S. theater lift fleet has been almost entirely composed of one type of aircraft, the C-
130, for years. Third, while the C-5 may have many hours of life remaining, it is an older
aircraft than the C-17. Proponents of purchasing additional C-17s point out that this
aircraft exploits newer technology that will make it easier and cheaper to maintain than
the C-5, and offers greater opportunities for future upgrades and modernization. Fourth,
the C-5’s unique ability to carry very large equipment such as engineering equipment and
Patriot missile batteries must be considered. DOD’s C-5 inventory has not met demands
to transport outsize/oversize cargo. Therefore, between 2003 and 2004, DOD contracted
with Russia to provide the AN-124 heavy lift aircraft to fly over 200 missions.9 Finally,
the C-5 carries almost twice the payload of the C-17. Eliminating the 120 C-5s from the
inventory removes the capacity of roughly 218 C-17s.
Option 2: Increased Use of Commercial Aircraft. Considering the current
shortfall in military strategic airlift capability, DOD may wish to consider increased use
of commercial aircraft, which offer many advantages over dedicated military aircraft.
They are numerous, tend to have longer range, and they are less expensive than military
aircraft. However, civilian aircraft also have limitations. They can’t carry oversize or
outsize cargo, they can’t conduct special missions like airdrops, or support special
operations. Also, they tend to congest airfields due to longer ground times, cargo
handling equipment requirements, lack of roll on/roll off capability, and less ramp
maneuverability.
It may be that DOD is already exploiting commercial aircraft to the maximum
potential benefit. The Air Force indicates in the MRS-05 study that they couldn’t use the
20.5 MTM/D of civilian airlift capability assigned for most of the halt phase of the
wartime scenarios studied, due to the limitations listed above. Also, enemy use of
weapons of mass destruction, such as chemical weapons, effectively deters civilian crews
from entering conflict areas. One civil aircraft initiative that may have some utility for
the military is the effort by Boeing, with the Air Force’s endorsement, to market a civilian
version of the C-17. Adding this aircraft to the Civil Reserve Air Fleet would address
the shortcomings listed above. Whether there is a sufficient market for these aircraft to
be commercially viable remains to be seen.
Option 3: Pursue Airships or Hybrid Airships. The Army, Navy, Joint Staff
and Defense Advanced Research Projects Agency (DARPA) are all exploring the
9 Gene Rector, “Russian Aircraft Getting U.S. C-5 Work,”
Macon Telegraph, Dec. 21, 2003.
Cynthia Di Pasquale, “Russian Planes Expand U.S. Airlift Capability Strained During OIF,
OEF,”
Inside the Air Force, Apr. 2, 2004.
CRS-5
development and use of airships, or hybrid airships, to carry very large military payloads
long distances. Airships, also called blimps, typically use helium to achieve lift and often
resemble the elongated, cigar-shaped
Goodyear blimp seen at major sporting events.
Hybrid airships also use gas buoyancy for much of their lift, but are shaped like an aircraft
wing to generate additional lift from aerodynamic forces. The airships currently being
explored could potentially carry payloads on the order of 500 tons to intercontinental
distances at speeds up to 100 miles per hour.10
In addition to their very large payloads and long range, airships and hybrids may
offer additional advantages applicable to the strategic airlift mission. They do not appear
to require as expensive and as specialized infrastructure as aircraft, and may be able to
deliver their payloads near the conflict, rather than an port or airfield miles to the rear.
Airships may potentially be capable of carrying a complete brigade-sized ground unit and
its equipment directly from “the fort to the fight,” overcoming logistic choke points and
mitigating the effects of limited forward basing. Airships and hybrids may be able to land
on water,11 which could prove valuable in realizing the Department of the Navy’s sea
basing concept.
Option 4: Reduce the Airlift Requirement. Another method for addressing
current and forecast airlift shortfalls is to reduce the size, weight or amount of equipment
to be moved. As part of their efforts to achieve a military transformation, all four services
are exploring ways to become lighter, leaner, or more deployable.
A key facet of the Army plan is the Stryker Brigade Combat Team. It is composed
of a mechanized infantry brigade of 3,500 personnel. Equipment will include 327
Stryker vehicles — which are lighter than today’s tanks — almost 600 wheeled vehicles,
155MM self-propelled artillery, air defense weapons, and engineering equipment. The
Army wants to be able to move one Stryker Brigade anywhere in the world in 96 hours.
It also wants to deploy one division in 120 hours and five divisions in 30 days.
Presumably, a variety of pre-positioning and transportation modes would be exploited to
meet this goal.
The Air Force’s principal effort in organizational innovation is the Expeditionary Air
Force Concept, or EAF. The purpose of the EAF is provide a structured and more
responsive way to deploy capabilities. The EAF will organize much of the Air Force into
10 Aerospace Expeditionary Forces (AEF) that will include combat, mobility, and combat
support forces. Each AEF includes approximately 175 aircraft, 20,000 people, and 6,000
tons of deployable equipment. The goal is to deploy one AEF anywhere in the world in
48 hours and up to five AEFs in 15 days.
Although both of these organizational initiatives appear to have merit, it is not clear
that either will reduce demands on the strategic airlift fleet. The amount and weight of
equipment in a Stryker brigade, for example, may be less than in current Army
organizations, but the desired speed of delivery is greater. Air Force analysts estimate that
10 Rich Tuttle, “DARPA Moves Ahead on Walrus,”
Aerospace Daily, Apr. 17, 2004. Anne
Roosevelt, “U.S. Military Considers Huge Airships for Lift Needs,”
Defense Week, Aug. 13,
2001.
11 Chuck Myers, “HULA: A Helium Magic Carpet?”
Proceedings, U.S.N.I., June 2003.
CRS-6
the early delivery of a Stryker Brigade and an AEF would require more airlift than moving
legacy forces during the halt phase of one MTW over a lengthier amount of time. Also,
moving five Army divisions in 30 days may require more airlift than currently planned
for the halt phases of two MTWs.12 The net effect the Service’s plans to become lighter,
leaner and more deployable may have on airlift may merit increased attention.
Option 5: Accept less Strategic Airlift Capability. The final option that may
be considered is to operate within the current and projected airlift capabilities. There
appear to be at least three arguments for this approach. First, there is some debate over
the realism of MRS-05’s plan for supporting two nearly simultaneous MTWs. General
Ryan, for instance, was quoted saying “We will never have enough for two MTWs. I
don’t think we can afford it. We have a one-major theater war airlift force.”13 General
Walter Kross, former commander of the Transportation Command also said “the airlift
force available for the next decade will be one that can handle a single major regional
contingency.”14 Furthermore, the actual U.S. airlift capabilities have been short of the
stated MTM/D requirement for 11 of the last 13 years.15 During this time, the United
States has successfully conducted operations in South West Asia, Bosnia and Kosovo.
It can thus be argued that the airlift requirement set by MRS-05 and other studies is
greater than required. A counter argument is that airlift requirements are designed to
satisfy a worst case scenario. Adherents to this perspective say the 54.5 MTM/D
requirement is justified, and the United States has been fortunate over the last 13 years not
to have faced the worst case scenario, in which case its airlift shortfall would have been
detrimental.
Second, it is argued that the MTM/D requirement can be lowered because strategic
airlift capacity is not the limiting deployment factor. Instead, the ability to move forces
may be limited by too few airfields and inadequate airfield infrastructure. Therefore,
acquiring more strategic airlifters might not only fail to satisfy airlift shortcomings but
employing them could actually exacerbate deployment problems. In Operation Allied
Force, for instance, “there were not enough air bases in the area immediately around
Kosovo to support all the aircraft...”16 This finding is significant because this theater
contains numerous airbases relative to other regions. Also, a study by the Army’s
Military Traffic Management Command found that the biggest roadblock to achieving the
service’s deployment goals is the limited infrastructure at forward airfields.17 Examples
of infrastructure shortfalls include limited ramp space and loading/unloading equipment.
12 Conversation with Air Mobility Command, SAF (LLW) and Department of the Air Force,
Deputy Chief of Staff for Plans and Programs, Global Mobility Division, Apr. 5, 2000.
13 Linda de France, “Ryan: We Will Never Have Enough Lift for Two Regional Wars,”
Aerospace Daily, June 22, 2000.
14 John Tirpak, “New Boss at Air Mobility Command,”
Air Force Magazine, Mar. 1997, p. 36.
15 Presentation by Brig. Gen. Robert Bishop to congressional staff,
Airlift Portion of MRS-05,
Slide #8, “Comparing Capabilities to Requirements,” Mar. 28, 2001.
16
Kosovo After Action Review. Secretary of Defense William S. Cohen and Gen. Henry H.
Shelton, Chairman of the Joint Chiefs of Staff. Senate Armed Services Committee, Oct. 14, 1999.
17 Kim Burger, “Army Study: Poor Forward Airfields Jeopardize Deployment Goals,”
Inside the
Army, Aug. 21, 2000.