BEIJING --- At the "State of the Air Force" held by the U.S. military in early March, Deborah Lee James, U.S. Secretary of the Air Force, announced the official name B-21 of their next-generation stealth Long Range Strike Bomber (LRS-B).
Military experts said that America's new-type stealth bomber is "tailored" for the Asia Pacific battlefield. As the first steal bomber developed by the U.S. in the 21st century, what are B-21's technical characteristics and is it capable of air defense penetration against major military powers around the world?
Targeting Asia Pacific and dealing with challenges from great powers
Three types of strategic bombers are currently serving in the U.S. military, named the B-52H, the B-1B and the B-2A.
In face of enemy's advanced air defense system, the B-52H and the B-1B are very weak in air defense penetration because they have no or limited stealth capability, while only 20 B-2A stealth bombers have been commissioned so far because of the high R&D cost and difficulties in maintenance, so they mainly play a deterrent role.
Besides, B-2 is a product that was commissioned in the 1990s. Many of its technologies cannot form absolute advantage over major military powers, and it is unable to effectively penetrate the enemy's intensive air defense system.
As of the 2015 fiscal year, the "three chariots" in the U.S. Air Force were 39 years old on average and their fuselage was very old, which was why the U.S. Air Force proposed the Next Generation Long Range Strike System (NGLRS) and LRS-B projects in 2010.
In the National Defense Strategic Guideline published by the U.S. Department of Defense in 2012, new-type long-range bomber was the only equipment that was mentioned for development. The "Asia Pacific rebalancing strategy" put forth by the U.S. also pointed out that the U.S. military should shift its focus from anti-terror operations to dealing with challenges from major military powers.
According to the U.S. standard for "potential rivals", they should be countries with a large territorial size and depth and strong air-defense and anti-ship capability. That's why the U.S. should have "stronger long-range strike capability" to meet the combat requirements in "anti-access/area denial" environment, which is also the requirement of the LRS-B project.
Ashton B. Carter, U.S. Secretary of Defense, and leaders of the U.S. Air Force announced in October 2015 that Northrop Grumman beat Boeing and Lockheed Martin and won the LRS-B contract that is worth US$55 billion, which was called by Carter the U.S. military's "strategic investment for the next 50 years". U.S. Secretary of the Air Force Deborah Lee James also noted that the bomber will enable the Air Force to deal with "high-level threats in the future".
Small aircraft with higher technological level
The U.S. Air Force has kept quiet about the specific performance indicators of B-21, and we could only make a primary conjecture based on information released by various parties. On appearance, B-21 is like a mini B-2A with smaller size and payload than the latter, but its technological level and the number of equipment is considerably superior to the latter.
On one hand, B-21 and B-2A have similar "standard configurations" for high-altitude stealth aircraft, such as flying wing tailless configuration, S-shaped inlet, embedded weapon cabin, integrated nozzle and fuselage, and pointed wing leading edge.
On the other hand, the aircraft uses advanced multi-function stealth materials that are capable of stealth performance against radar/infrared/visible light. It may also overcome electromagnetic interference from the enemy and its better infrared stealth performance can largely reduce the infrared radiation of B-21, thus improving the air defense penetration capability.
Considering America's technical accumulation for stealth fighter jets, it is sure to arm the B-21 with intelligent tactical stealth capability. Relevant data show that B-21 will be equipped with cutting-edge task sensors so that aircraft, either independently or in cooperation with other aircraft, can perceive and judge the battlefield threat more comprehensively and make tactical plans in a real-time way to enhance the strike capability.
Moreover, the U.S. military will make B-21 stronger in capability expansion. The general embedded weapon cabin can hold multiple types of regular guided missile bombs, cruise missiles, earth penetrators and next-generation air-launched cruise missiles that can carry nuclear warheads. It is said that this aircraft will have two types, manned and unmanned, the latter able to carry out operations in the more dangerous and sensitive hinterland of the enemy.
The U.S. Air Force believed that B-21 will ensure effective deterrence against the "strongest potential rival" at least before 2040.
Worrisome air defense penetration capability in face of military powers
At present, B-21 is in the engineering and manufacturing stage. The U.S. military plans to purchase more than 100 of it, but some of its officials are discussing the possibility of increasing the purchase to 200 given the need for "warfare in the Asia Pacific".
Some experts said that if the U.S. military deploys B-21 in the Asia Pacific, it will exert major impacts on the regional security and even trigger a new round of arms race.
But does B-21 have overwhelming advantage over major military powers around the world? The answer is negative.
It is learnt that when B-21 was in the demonstration stage, the U.S. military, based on intelligence about and its judgment of "potential rivals", believed the aircraft was able to penetrate the enemy's future air defense system, launch precision strike on it and maintain standby coverage for more than an hour, but that sounds a little "self-bragging".
On one hand, both stealth and anti-stealth technologies are in the period of high-speed development, and new and better concepts and technologies keep showing up. B-21 cannot be commissioned on a large scale until after 2030, and its stealth capability is to be tested in face of the multi-layer 3D air defense systems, especially the multiple new detection equipment such as anti-stealth radar, adopted by major military powers.
On the other hand, B-21, like other strategic bombers, needs well developed supportive functions and a fixed airport, but fixed facilities are the top targets in the enemy's first round of attack, so B-21's airport will be more "fragile" than B-21 itself when faced with powerful winged missiles and strategic ballistic missiles. As a result, B-21 may find it difficult to assure durable combat capability.
Although the B-21 bomber is not a revolutionary aircraft with absolute deterrent force like B-2A, it will still display asymmetrical advantages in most cases when the enemy's long/medium/short-range detection system and interception system has one or more weak links.
In sum, stealth capability remains the focus of weapons and equipment research in the new age. B-21 that stresses the adoption of relatively mature technology and reduction of development and manufacturing cycle also needs to have state-of-the-art omni-directional broadband stealth capability. Therefore, the game between stealth and anti-stealth performance remains one of the themes of future warfare.