Introduce the performance of B2!

Country of development: American name and model: B-2 "Spirit" Development unit: Northrop, USA? The cost of Grumman Military Aircraft Systems Department: Each aircraft is about $600 million. In the end, with the development cost, each plane exceeded $2 billion. Identity: active duty. At present, * * * is equipped with 2 1 frame.

I. Overview

B-2 Ghost is a heavy stealth bomber of the US Air Force. It can take off from the United States or frontier bases, penetrate the enemy's complex air defense system and attack high-value, strong defense and the most urgent targets without supporting aircraft escort. It is an effective deterrent and combat force of the US Air Force in the 2nd/Kloc-0th century. At present, B-2 only has B-2A.

Northrop, USA? Grumman Military Aircraft Systems Department is the main contractor of the B-2 bomber, responsible for the design and synthesis of all aircraft systems. Boeing, Hughes and General Electric Company also participated in the development of various aircraft components and training equipment.

Because of its advanced nature, confidentiality and maintainability, coupled with low output and inflation, B-2 is expensive. During the period of 1995, according to the contract between the US Air Force and Northrop Corporation, the manufacturer manufactured 20 B-2A aircraft at the production rate of 3 aircraft per year, and each aircraft cost about 600 million US dollars. Finally, with the development cost, the cost of buying a B-2A is more than $2 billion.

B-2 was developed by 1978, and the first aircraft flew in July 1989. 1t B- 2 bomber "Missouri Ghost" was delivered in February 1993. The us air force is currently equipped with 2 1 frame.

1, R&D background

The idea of developing the B-2 stealth bomber began with 1975. At that time, the Advanced Planning Agency under the US Department of Defense issued a project code-named "Harvey", which was implemented in the Air Force, from which the XST (meaning experiment, stealth and combat) plan was derived. In this plan, the American military scientific research community put forward the idea of applying stealth technology to aircraft for the first time. Lockheed, which has rich experience in military aircraft development, first won the military development contract and soon produced two full-scale XST prototypes, which initially proved the feasibility and effectiveness of stealth technology applied to aircraft.

At that time, the cold war was still raging. In order to secretly break through the Soviet air defense network and discover and destroy the Soviet mobile intercontinental ballistic nuclear missile launcher and other important strategic targets, the US Air Force proposed to build a new strategic bomber, emphasizing penetration capability, requiring that it can avoid aerial radar detection and sneak into the enemy's depth, with a success rate of 80%. Therefore, the Air Force has drawn up the plan of "Saber Armor-piercing Projectile" and put the application of stealth technology on the concrete agenda. Because the prototype submitted by Lockheed was well received, the Air Force awarded the contract for the production of F- 1 17A stealth fighter to this company. With the production of stealth fighters, the US Department of Defense and congressional dignitaries began to accept the concept of "stealth bomber" and formally approved the application report of the Air Force to develop this kind of aircraft in 1977. Subsequently, the US Air Force officially named the development project of the new stealth bomber "Advanced Technology Bomber (ATB)". This is the original name of the B-2 stealth strategic bomber.

2.R&D process

1In September, 1980, the US Air Force asked Lockheed and Northrop to make suggestions in five aspects: performance, cost, logistics support, project management and safety. Lockheed's plan is SeniorPeg (old prosthetic leg) and Northrop's is Senior lce (old diamond). 198110/On October 20th, Northrop Company won the competition and changed its code name to old CJ to commemorate CJ Kelly, deputy director of the US Air Force who died of cancer. Major aviation technology companies in the United States quickly invested in the stealth bomber program. Boeing is responsible for the rear middle section, outer wing, fuel system, weapon launching system and landing gear of titanium alloy flying wing. LTV is responsible for the middle section of flying wing, aluminum-titanium alloy structure and composite structure. F119-GE-1/KLOC-0 turbofan engine specially modified by General Electric Company. Northrop is responsible for manufacturing the front middle section, cockpit and final assembly.

In the early 1980s, B-2 experienced several major design changes. From 65438 to 0984, the design of the main wing has changed a lot, because the Air Force requires the aircraft to penetrate not only from high altitude, but also from low altitude, which brings a series of problems, such as improving the lift of the aircraft, enhancing the strength of the mechanical structure and further reducing its radar reflection cross section. The above delay makes it take several years for the design of the aircraft to be finalized.

The development process of B-2 is the most confidential military scientific research project in the United States after the Manhattan Project to develop the atomic bomb. 1On April 8th, 982, Northrop bought an idle factory in Pico Lafollas, a suburb of Los Angeles, and converted it into a secret factory. 24-hour monitoring by military and security personnel. In order to prevent Soviet submarines from sneaking into California offshore to monitor the electromagnetic radiation emitted by computer software systems, Picasso's computer-aided design/manufacturing terminal equipment rooms are all shielded by special metal plates. Each computer is equipped with a special cover, so that unauthorized personnel can't see the screen. Workers in all key positions are tested by polygraph to prevent spies and drug addicts. Only a few senior managers know the details of the plan, and the monitoring is stricter. The Canadian wife of a vice president of Northrop Corporation who participated in the project was forced to be naturalized in the United States. Registered a fake company far away from the factory and handed over the parts shipped by subcontractors. These parts were transported to Picasso by unmarked trucks in the middle of the night. Air Force officials were asked to change into casual clothes when they visited Biko Labra. What's more, only eight members of the huge parliament know about it.

The outside world first learned about B-2 on1April 20th, 988, and the US Air Force showed an inaccurate hand-painted color map of B-2 aircraft for the first time, which shocked the world. In the same year1October 22nd, 165438+, the B-2 prototype with the number AV- 1 finally, "however, we called it a thousand times and urged it a thousand times before she set off for us", which became a behemoth that the American public rushed to see. During this period, the B-2 prototype has undergone many secret flight tests and strict inspections by the military, and the manufacturer has to constantly make design modifications according to various opinions and harsh requirements put forward by the Air Force. 1983 revised the development plan, changing the B-2 from high-altitude penetration to low-altitude penetration bomber. 1since June 1987, the electronic equipment of B-2 has been installed on KC- 135 for flight test. According to the plan, six B-2s are designated for the R&D test flight, which will last for 3,600 hours. Except for the second test machine, the other five will be converted into standard machines and put into use after completing the flight test plan. In addition, two airframes were manufactured for static test. The first prototype 1988, 1 1, 10, and the first test flight of 1989 was conducted in July. The first prototype mainly carried out aerodynamic and airworthiness test flights; The second prototype mainly carries out load test flight and extended envelope test flight, and there is no standard stealth configuration; The third and fourth prototypes are equipped with a full set of electronic equipment, which is mainly used for electronic equipment, stealth and weapon flight test; The fifth and sixth aircraft are mainly used for weapons and actual service test flights. Five years later, the US Air Force finally received the first operational B-2A aircraft in June 5438+February 0993. 1April 2, 997, the first batch of six B-2A stealth bombers officially entered service.

Second, the performance indicators

The B-2A bomber has a fuselage length of 20.9 meters, a height of 5. 1 m, a wingspan of 52.12m, a maximum load of18144kg (400,000 pounds) and a service ceiling of15240m (50,000 feet). The aircraft is equipped with four F118-GE-100 turbofan engines produced by American General Dynamics Company. Each engine has a thrust of 7,854 kg (17,300 lb) and two crew members. Without aerial refueling, the operational range of the aircraft can reach 12000. The air flight time of each mission is generally not less than 10 hour, and the US Air Force claims to have the ability of "global arrival" and "global destruction".

Third, the structural characteristics

1, stealth characteristics

B-2A has excellent stealth performance. Stealth performance first comes from appearance. First of all, its fuselage is flat, and it adopts tailless flying wing with wing-body fusion. The leading edge of the wing is straight and the wing is swept back 33 degrees. The nose of the plane forms an acute angle with the tip of the wing, and the trailing edge of the wing is double "W" shaped like a sawtooth, which looks like a huge black bat. The huge serrated trailing edge is composed of 10 straight edges, so that radar waves can be reflected from the trailing edge and the upper edge, and deviate from the tail area of the aircraft at a large angle.

B-2A has no vertical tail, which greatly reduces the radar reflection cross section of the whole aircraft. There is no weapon cabin and weapon rack under the fuselage, and even the engine cabin and landing gear cabin are buried under the smooth wing to avoid the reflection of radar waves. The whole fuselage of B-2 aircraft is made of carbon fiber, graphite and other composite materials except the main beam and engine room, which are not easy to reflect radar waves. In addition, these different composite parts are not assembled by rivets, but by high pressure die casting. In addition, the leading edge of the alum wing is completely covered with a special absorbing material (RAM). The two square protruding parts located in the front of the wing and equipped with radar scanning antenna array also use special absorbing materials. In addition, B-2A is sprayed with special absorbing coating, which greatly reduces the echo of enemy detection radar.

Except for the main beam and engine room, the whole fuselage of B-2A aircraft is made of composite materials such as carbon fiber and graphite, which makes it difficult to reflect radar waves. And these different composite parts are not assembled by rivets, but by high pressure die casting. In addition, the whole body is sprayed with special absorbing paint, which greatly reduces the echo of enemy detection radar. The radar cross-sectional area of the whole aircraft is only 0. 1 ~ 0.00 1 m2, which is equivalent to a bird, only1110. All weapon systems are hidden in the fuselage, and there is no weapon rack outside the fuselage. There is a rotating launcher inside the fuselage, and even the engine compartment and landing gear compartment are buried under the smooth wing, which not only reduces the flight resistance, but also effectively avoids radar detection. The aircraft adopts a honeycomb structure that can absorb radar waves, and the materials and gray paint on the outer surface of the aircraft have the characteristics of reducing radar wave reflection and thermal radiation.

The cockpit of B-2

The cockpit shape of B-2

2. Power plants

The engine inlet of B-2A aircraft is placed above the wing in an S shape, which can naturally attenuate the incident detection radar waves after repeated refraction and cannot be reflected back. The engine nozzle is deeply placed in the wing and is also honeycomb-shaped, so that radar waves can enter but not exit. In addition, the engine assembly is also equipped with an airflow mixer, which can guide the cold air flowing through the airfoil into the engine and continuously reduce the outer temperature of the engine. The nozzle is wide and flat, so people can't see the nozzle at the tail of the plane. Especially, due to the nozzle temperature adjustment technology, the infrared exposure signal of the nozzle part is greatly reduced, and the stealth performance of the aircraft is greatly enhanced. In addition, sulfuric acid chlorofluoride is sprayed into the exhaust gas discharged from the engine to eliminate the visual wake of the engine and finally achieve the purpose of stealth.

B-2 is powered by four afterburner turbofan engines of General Electric Company F118-GE-110. The maximum thrust of a single engine is 7854 kg, which enables the B-2 aircraft to fly at supersonic speed, ensuring the maximum takeoff weight 152635 kg. Without aerial refueling, the combat range can reach1.2000 km, and once aerial refueling, it can reach1.8000 km. The air flight time of each mission is generally not less than 10 hour, and the US Air Force claims to have the ability of "global arrival" and "global destruction". B-2 aerial refueling equipment is installed on the upper center line behind the cockpit of the aircraft.

Four. Arms control and electronic systems

1, fire control system.

There are many advanced airborne electronic systems on the B-2A aircraft, such as detection, navigation, aiming and electronic countermeasures. B-2A detection radar is AN/APQ- 18 1 array radar, which is manufactured by Hughes Company. It has the advantages of narrow frequency spectrum and difficult signal interception by the enemy. This electronically scanned array radar system has two radar antenna arrays, and its characteristic is that it can scan in different angles and directions only by changing and combining the positions of signal arrays without additional rotating or swinging antennas. Its working frequency is12-18 GHz, and its sidelobe is very small, so it has strong anti-electronic interference ability. There are 2 1 working modes * *, among which the most prominent are synthetic aperture radar working mode and anti-synthetic aperture radar mode. The former is mainly used to scan the land landforms, and can clearly obtain the land scanning image with the distance of 16 1 km, which can be used by aircraft to bomb ground targets; The latter is mainly used to identify and capture maritime targets, and the longest effective distance can reach 128km. B-2A bomber can make use of terrain matching and terrain avoidance technology, so that it can penetrate enemy airspace at low altitude to carry out bombing missions. The B-2A is also equipped with an advanced NSS navigation system. The system includes two kinds of navigation equipment, one is inertial navigation unit, and the other is NAS-27 astronomical navigation unit, which provide advanced automatic navigation and the most commonly used constellation positioning navigation for B-2A respectively, thus ensuring flight safety. The target aiming system on the plane adopts the global positioning auxiliary aiming system, which can lock the selected target and enlarge it by four times, which is convenient for the crew to identify and aim at the target, thus improving the hit accuracy of the bomb. The error of a bomb hitting the target is usually less than 6 meters. The B-2A is also equipped with an electronic warfare system of APQ-50 model. The system can not only provide radar early warning for aircraft, but also quickly detect the azimuth coordinates of enemy radar. The ZSR-62 active electronic warfare system on the plane can quickly and actively interfere with and suppress the enemy. There are some other electronic systems on the plane, such as TCN-250 TACAN system, VIR- 130A automatic landing system, AN/APR-50 radar warning receiver and ZSR-63 defense auxiliary equipment. In addition, there is a communication management system and various display systems in the cockpit, which can display the information and images obtained by all sensors comprehensively for the crew to judge the handling situation and contact with relevant departments on the ground. In front of the seats of the two crew members, there are four full-color multi-function display screens with the size of 15.2 cm respectively, which makes the situation clear at a glance.

2. Weapons and equipment.

The B-2A bomber has no external points and has two internal weapon compartments, each equipped with a rotating launcher and two bomb compartments. B-2 can carry18160kg (40,000 lbs) ammunition, including conventional ammunition, nuclear weapons and precision-guided ammunition. The nuclear weapons that B-2 can carry are: 16 B6 1 ground-penetrating nuclear bomb, which can strike deep-buried and reinforced targets; 16 B83 strategic free-fall nuclear bomb, 16 AGM- 129 advanced cruise missile and16agm-131slam missile. Conventional ammunition: 80 227kg MK82 bombs, 16 908kg MK84 bombs, 34-36 CBU-87 bombs, 34-36 CBU-89 bombs and 34-36 CBU-97 cluster bombs. Precision guided ammunition: 80 GBU-30 joint direct attack ammunition of 227kg, 908kg GBU-32 joint direct attack ammunition 16, gbu 27 8, EGBU-28 8, GBU-36 8, GBU-37 8, AGM 8- 16. Eight AGM- 137 attack missiles launched outside the defense zone.

B-2' s range and bombing capability

V. Evolution of equipment and models

The US Air Force has 2 1 B-2 bombers in active service, all of which belong to the 509th wing of the US Air Force Combat Command and are stationed at Whiteman Air Force Base in Missouri, but only 16 B-2 bombers are in combat readiness. B-2 aircraft has experienced three types from development to equipment. At the time of initial delivery, six were test aircraft, 10 was Brock-10, three were Brock -20 and two were Brock -30. In June 2000, all B-2 bombers of Brock 10 and 20 were upgraded to Brock -30 aircraft.

"Brock-10" was delivered for the first time from 1993 to 12 and continued until 1996. This B-2 can only carry 16 B83 nuclear bomb or 16 MK84 conventional bomb, aiming at soft targets in the air and high altitude.

Brock -20 was manufactured between April 1996 and February 16, and made 6 1 nuclear bomb, 36 cluster bomb and 16 GPS-guided transition bomb. This type of aircraft has the ability of terrain tracking and terrain avoidance, and can perform low-altitude bombing missions.

1 Brock -30 aircraft was delivered from1August 7, 1997 to1May 1999. This type of aircraft has higher terrain avoidance ability and terrain tracking ability than Brock -20 aircraft, and can deliver joint direct attack ammunition and joint defense missiles outside the defense zone.

Sixth, the development trend of aircraft

With the change of the world, the combat mission of B-2 has also changed. At present, Northrop Grumman has begun to make a series of improvements to the B-2 to meet the new operational needs of the US Air Force. These improvements include: optimizing the communication and radar system, bomb rack and applying new and more effective stealth coating, which provides greater flexibility for US military generals in wartime decision-making and control implementation plans.

1, communication system.

The US Air Force will use the next generation VHF satellite communication system to replace the two-way communication equipment of B-2. B-2' s new communication system can be used to link national command institutions in the nuclear environment, which can significantly improve the bandwidth and data transmission and processing capabilities between aircraft. B-2' s new system is more conducive to the aircraft receiving the latest target information when performing tasks. In June 2003, according to the B-2 over-the-horizon communication plan, the US Air Force planned to install the Link- 16 data link on the B-2 bomber. Link- 16 data link transmits data information safely at high speed and has anti-blocking ability. Link- 16 can transmit all kinds of tactical data information between command and control machines, combat aircraft, missiles and other weapon system platforms, as well as between combat units, so as to realize the sharing of battlefield resources. The biggest advantage of Link- 16 data link is that if one participant in the link is destroyed or fails, the whole data transmission system will not collapse. The application of Link- 16 data link will enable B-2 pilots to know the position of the aircraft in real time. At the same time, it also has the interface ability with the communication satellite PRC- 1 17 radio station produced by Harris Company, supports the interface ability of Hawkeye system software, and receives tactical data links J(60 16B) and 30 1 1 App. Protocol and receive the position and time information of global positioning system.

2. Radar system.

As the TV and film industries will start to use some new wireless communication frequency bands around 2007, it may conflict with the frequency bands currently used by B-2 airborne radar. By then, the radar of the B-2 bomber may cause serious damage to the media broadcasting and communication satellites in the above frequency bands. The Air Force plans to transform Raytheon's APQ- 18 1 radar so that it will not conflict with commercial satellites. A study currently completed by the Air Force tends to upgrade APQ- 18 1 radar, including the use of active electronically scanned array antennas. By 2006, six B-2 bombers will be equipped with active electronically scanned array radar system, and before 20 10, all B-2s will be equipped with this system.

The US Air Force's B-2 bomber radar modernization plan (B-2 RMP) will improve the existing radar system to solve the possible conflicts in the frequency bands used. According to the requirements of the federal government, the radar frequency must be changed to the frequency band specified by B-2. The improved radar system design should enable the B-2 bomber to meet the operational requirements of the aircraft in stealth characteristics, range, load and precise weapon delivery. When the two key technologies are mature and close to maturity, B-2 RMP began to enter the research and development stage in August 2004. All key technologies should make a breakthrough in the design review in June 2005. At present, 7 1% of the design drawings have been issued, and it is expected that 85% ~ 95% of the drawings will be issued during the design review in June 2005. The official in charge of the project said that the production maturity standard will be formed during the research and development, and it has not yet been determined whether the standard includes production process control data. During the research and development period, it is planned to manufacture six radars for training pilots of B-2 combat troops before completing the flight test.

Total investment of B-2 RMP project: USD 654.38+USD 204 million, including R&D expenses of USD 693.7 million; The procurement cost is $565,438+006 million.

Project schedule:

In June 2002, the project started and entered the conceptual research stage.

In August 2004, it entered the research and development stage.

From June 5, 2005 to 10, the government responsibility office (GAO) was inspected.

In June 2005, a project design review was conducted.

Low-speed initial production started in February 2007.

In June 2007, 5438+ 10 formed its initial operational capability.

Full-speed production in February 2008

Procurement completed in 2009

3. Bomb rack.

With the air force becoming more and more interested in high-precision weapons, Northrop upgraded the bomb rack on the B-2 aircraft to enable it to carry 80 227 kg joint direct attack ammunition. In addition, B-2 also plans to install 2,270 kilograms of earth-penetrating bombs and small smart bombs (namely "small caliber ammunition", SDB). Northrop Grumman began to install new bomb racks on the first four B-2 bombers in 2004. The B-2 bomber can drop 16 908kg JDAM guided bombs in one voyage with the active bomb rack, and 80 227kg JDAM guided bombs in one voyage with the new bomb rack. The US Air Force plans to replace all B-2 bombers with new bomb racks by 2006. In addition, in March 2005, the US Air Force began to install 2270 kilograms of GBU-28 extended-range earth-penetrating guided bombs for B-2 bombers.

4. New stealth coating.

Northrop is trying to enhance the performance of B-2 to avoid being detected by enemy radar. After several years of research, the company has developed a stealth coating called Advanced High Frequency Material (AHFM), which is an epoxy-based material that can effectively absorb radar signals and replace the absorption band of nearly 3,000 feet currently used by B-2. This coating material can be sprayed like paint, instead of using a wave-absorbing tape with complicated procedures as before. Its painting work can be carried out under ordinary maintenance conditions without a highly complicated closed hangar, and the stealth performance of the aircraft remains unchanged. In the past, it was inefficient and time-consuming to cover the gaps of these covers with absorbent tape. The newly developed spray absorbing material effectively overcomes the above shortcomings and greatly reduces the maintenance time. The coating work was carried out at Antilop Valley Manufacturing Center in Novo Gruber, Palmdale, California, using a robot spraying system. Using robot spraying system can not only reduce working hours and save manpower, but also make the accuracy reach one millionth of an inch. In August 2004, Northrop Grumman delivered the first B-2 bomber with a new stealth coating to Whiteman Air Force Base. The replacement of new coatings for other aircraft will be carried out step by step with their daily maintenance procedures. Routine maintenance of about 3 B-2 aircraft will be carried out every year, and it is expected that all B-2 aircraft will be updated in 201kloc-0/year.

Seven. Operation and use

The main operational task of B-2 aircraft is to suddenly enter enemy airspace by stealth performance and attack strategic targets such as command institutions, communication facilities and missile bases with nuclear bombs or conventional weapons. B-2 usually carries out long-range raids when carrying out attack missions, and can strike anywhere in the world through aerial refueling. However, because B-2 can't be invisible to visible light, it usually performs attack tasks at night.

B-2 is at Anderson Air Force Base in Guam

In order to support the air force's global strike mission against the task force, the US Air Force has built 1 B-2 aircraft bunkers in Fairford, England, and four B-2 aircraft bunkers on Diego Garcia Island in the Indian Ocean. This kind of bunker adopts skeleton inflatable skin structure, with an inner width of 76.2 meters, a width of 38. 1 meter and a height of 16.76 meters, which can resist the pressure of strong wind and heavy snow at a speed of 177 kilometers per hour. Equipped with air conditioner, humidifier and other equipment inside, the environment is controllable and can be kept within the tolerable range of B-2 sensitive paint. The U.S. Air Force requires such bunkers to be easy to transport and can be quickly installed and opened. The bunker deployed in the front line will also be used as the semi-permanent hangar of B-2, thus greatly reducing the maintenance time of the aircraft and correspondingly improving the mission dispatch rate of the aircraft. B-2 may use these hangars to strike anywhere in the world within 24 hours.

B-2 aircraft forward base bunker

B-2 hangar

Eight, actual combat performance

B-2 has served in three wars. On March 24th, 1999, two b-2s took off from Whiteman air base. After 30 hours of continuous flight and two aerial refueling, they dropped 32 908 kg joint direct attack ammunition on Yugoslav targets, which was the first time that B-2 bombers participated in actual combat. During the whole Kosovo war, six B-2s dispatched 45 sorties and dropped 656 joint direct attack bombs on important targets in Yugoslavia. B-2 flew less than 1% of the total aircraft in the war, but the bombs dropped reached 1 1% of the total bombs dropped. Destroyed nearly 33% of Yugoslavia's targets.

In the war in Afghanistan, three days before the war, * * * six B-2s took off from the mainland, passed through the Pacific Ocean, Southeast Asia and the Indian Ocean, carried out air strikes on Afghanistan, and then landed in Didao, setting a new record of 44 hours of continuous combat flight and dropping 96 joint direct attack ammunition.

During the Iraq war, B-2 aircraft flew 49 sorties. Among them, 27 sorties took Whiteman as the landing base, flew over the Atlantic route and carried out long-range raids, with a flight time of about 35 hours. The other 22 sorties were based on a forward base and carried out precise attacks on Iraq's command, control and communication facilities.