B2 Spirit
The B-2 Spirit is a
multi-role bomber capable of delivering both conventional and nuclear
munitions.
Along with the B-52
and B-1B, the B-2 provides the penetrating flexibility and effectiveness
inherent in manned bombers. Its low-observable, or "stealth,"
characteristics give it the unique ability to penetrate an enemy's most
sophisticated defences and threaten its most valued, and heavily defended,
targets. Its capability to penetrate air defences and threaten effective
retaliation provide an effective deterrent and combat force well into the
21st century.
By eliminating the standard
fuselage and wing structure from the B-2, the entire plane becomes a
lifting body. The aircraft is controlled by structures called elevons.
The blending of
low-observable technologies with high aerodynamic efficiency and large
payload gives the B-2 important advantages over existing bombers. Its low-observability
provides it greater freedom of action at high altitudes, thus increasing
its range and a better field of view for the aircraft's sensors. Its
unrefuelled range is approximately 6,000 nautical miles (9,600
kilometres).
The B-2's low
observability is derived from a combination of reduced infrared, acoustic,
electromagnetic, visual and radar signatures. These signatures make it
difficult for the sophisticated defensive systems to detect, track and
engage the B-2. Many aspects of the low-observability process remain
classified; however, the B-2's composite materials, special coatings and
flying-wing design all contribute to its "stealthiness."
The B-2 has a crew of
two pilots, an aircraft commander in the left seat and mission commander
in the right, compared to the B-1B's crew of four and the B-52's crew of
five.
The engines of the B-2 Spirit are
embedded in the wings, with intakes and exhausts both on the top
surface
The B-2 is intended to
deliver gravity nuclear and conventional weapons, including
precision-guided standoff weapons. An interim, precision-guided bomb
capability called Global Positioning System (GPS) Aided Targeting
System/GPS Aided Munition (GATS/GAM) is being tested and evaluated. Future
configurations are planned for the B-2 to be capable of carrying and
delivering the Joint Direct Attack Munition (JDAM) and Joint
Air-to-Surface Standoff Missile.
B-2s, in a
conventional role, staging from Whiteman AFB, MO; Diego Garcia; and Guam
can cover the entire world with just one refuelling. Six B-2s could
execute an operation similar to the 1986 Libya raid but launch from the
continental U.S. rather than Europe with a much smaller, more lethal, and
more survivable force.
Background
The B-2 development
program was initiated in 1981, and the Air Force was granted approval in
1987 to begin procurement of 132 operational B-2 aircraft, principally for
strategic bombing missions. With the demise of the Soviet Union, the
emphasis of B-2 development was changed to conventional operations and the
number was reduced to 20 operational aircraft, plus 1 test aircraft that
was not planned to be upgraded to an operational configuration. Production
of these aircraft has been concurrent with development and testing.
The first B-2 was
publicly displayed on Nov. 22, 1988, when it was rolled out of its hangar
at Air Force Plant 42, Palmdale, Calif. Its first flight was July 17,
1989. The B-2 Combined Test Force, Air Force Flight Test Center, Edwards
Air Force Base, Calif., is responsible for flight testing the engineering,
manufacturing and development aircraft as they are produced. Three of the
six developmental aircraft delivered at Edwards are continuing flight
testing.
Whiteman AFB, Mo., is
the B-2's only operational base. The first aircraft, Spirit of Missouri,
was delivered Dec. 17, 1993. Depot maintenance responsibility for the B-2
is performed by Air Force contractor support and is managed at the
Oklahoma City Air Logistics Centre at Tinker AFB, Okla.
The prime contractor,
responsible for overall system design and integration, is Northrop
Grumman's Military Aircraft Systems Division. Boeing Military Airplanes
Co., Hughes Radar Systems Group and General Electric Aircraft Engine Group
are key members of the aircraft contractor team. Another major contractor,
responsible for aircrew training devices (weapon system trainer and
mission trainer) is Hughes Training Inc. (HTI) - Link Division, formerly
known as C.A.E. - Link Flight Simulation Corp. Northrop Grumman and its
major subcontractor HTI, are responsible for developing and integrating
all aircrew and maintenance training programs.
The Air Force is
accepting delivery of production B-2s in three configuration
blocks--blocks 10, 20, and 30. Initial delivery will be 6 test aircraft,
10 aircraft in the block 10 configuration, 3 in the block 20
configuration, and 2 in the block 30 configuration.
Block 10
configured aircraft provide limited combat capability with no capability
to launch conventional guided weapons. The Block 10 model carries only
Mk-84 2,000-pound conventional bombs or gravity nuclear weapons. B-2s in
this configuration are located at Whiteman Air Force Base and are used
primarily for training.
Block 20
configured aircraft have an interim capability to launch nuclear and
conventional munitions, including the GAM guided munition. The Block 20
has been tested with the Mk-84, 2,000-pound, general-purpose bombs and
the CBU-87/B Combined Effects Munition cluster bombs (low-altitude,
full-bay release).
Block 30
configured aircraft are fully capable and meet the essential employment
capabilities defined by the Air Force. The first fully configured Block
30 aircraft, AV-20 Spirit of PENNSYLVANIA, was delivered to the Air Force
on 07 August 1997. Compared to the Block 20, the Block 30s have almost
double the radar modes along with enhanced terrain-following capability
and the ability to deliver additional weapons, including the Joint Direct
Attack Munition and the Joint Stand Off Weapon. Other features include
incorporation of configuration changes needed to make B-2s conform to the
approved radar signature; replacement of the aft decks; installation of
remaining defensive avionics functions; and installation of a contrail
management system.
All block 10, 20, and
test aircraft are to eventually be modified to the objective block 30
configuration. This modification process began in July 1995 and is
scheduled to be completed in June 2000.
The B-2 fleet will
have 16 combat-coded aircraft by the second quarter of FY00.
The B-2 Spirit has a crew of two, a
pilot in the left seat and a mission commander in the right, compared
to the B-1B crew of four and the B-52 crew of five.
Link-16 –
Providing Line-of-Sight (LOS) data for aircraft-to-aircraft,
aircraft-to-C2, and aircraft-to-sensor connectivity, Link-16 is a combat
force multiplier that provides U.S. and other allied military services
with fully interoperable capabilities and greatly enhances tactical
Command, Control, Communication, and Intelligence mission effectiveness.
Link-16 provides increased survivability, develops a real-time picture of
the theatre battlespace, and enables the aircraft to quickly share
information on short notice (target changes).
Connectivity –
DoD requires survivable communications media for command and control of
nuclear forces. To satisfy the requirement, the Air Force plans to deploy
an advanced Extremely High Frequency (EHF) satellite communications
constellation. This constellation will provide a survivable, high
capability communication system. Based on favourable results from a funded
risk reduction study, the B-2 will integrate an EHF communication
capability satisfying connectivity requirements.
Digital Engine
Controller - The current analogue engine controllers are high failure
items, and without funding, ACC will be forced to ground aircraft
beginning approximately FY08. Replacement of the engine controllers will
improve the B-2’s performance and increase supportability, reliability,
and maintainability. Computers/Processors - With advances in
computer technology and increased demands on the system, the B-2’s
computers will need to be replaced with state-of-the-art processors.
Although reliable, maintaining the present processors will become
increasingly difficult and costly.
Signature
Improvements - The B-2’s signature meets operational requirements
against today’s threats. As advanced threats proliferate, it will be
prudent to investigate advanced signature reduction concepts and determine
if it is necessary to improve the B-2’s low observable signature.
CANDIDATE LONG TERM UPGRADES BEYOND FY 15 TOTAL The basis for the useful
life of the B-2 includes data from initial Developmental Test and
Evaluation analysis. Data indicates the aircraft should be structurally
sound to approximately 40,000 flight hours using current mission profiles.
Analysis further suggests that the rudder attachment points are the first
structural failure item. The B-2 has not implemented an ASIP similar to
the other bombers, and this makes it difficult to predict the economic
service life and attrition rate. However, a notional projection, based on
the B-52, predicts one aircraft will be lost each 10 years. This attrition
rate, plus attrition due to service life, will erode the B-2 force below
its requirement of 19 aircraft by 2027.
Tactical delivery
tactics use patterns and techniques that minimize final flight path
predictability, yet allows sufficient time for accurate weapons delivery.
For conventional munitions. Bomb Rack Assembly (BRA) weapons
delivery accuracies depend on delivery altitude. For a weapons pass made
at 5,000 ft above ground level [AGL] or below, the hit criteria is less
than or equal to 300 feet. For a weapons pass made above 5,000 feet AGL,
the hit criteria is less than or equal to 500 feet. Similarly, Rotary
Launcher Assembly (RLA) delivery of conventional or nuclear weapons
(i.e. Mk-84, B-83, B-61) is altitude dependent. For a weapons pass made at
5,000 feet AGL or below, the hit criteria is less than or equal to 300
feet. For a weapons pass made above 5,000 ft AGL, the hit criteria is less
than or equal to 500 feet. The hit criteria for a weapons pass made with
GAM/ JDAM munitions is less than or equal to 50 feet.
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