B-2: stealth bomber

MILITARY B-2 SPIRIT

A B-2 Spirit at Andersen Air Force Base, Guam in January 2017. Close to 200 airmen and three B-2s deployed from Whiteman Air Force Base, Missouri to support US Strategic Command bomber assurance and deterrence missions.
TSgt Andy Kin/US Air Force

The Northrop Grumman Block 30 B-2 Spirit stealth bomber is like nothing else that flies: a tailless flying wing that offers both low observable stealth and high aerodynamic efficiency for long-range missions with large payloads. Its combat use requires it to fly halfway around the world to strike high-value targets. The need to counter threats armed with weapons of mass destruction makes the B-2’s unique operational capabilities critical to the US national command authorities.

Current fleet, current configuration

Based at Whiteman Air Force Base, Missouri, the B-2 equips the 509th Bomb Wing and the associated 131st Bomb Wing, a unit of the Missouri Air National Guard. It remains the most advanced US strategic bomber, even though it is 25 years old. It incorporates older, second-generation stealth technology, which is less effective and, more significantly, imposes higher sustainment costs than that associated with more recent stealth designs, contributing to its high $122,000 per-hour flight cost. This means B-2 pilots – over 100 are based at Whiteman – normally get to fly about 100 hours a year in the aircraft, with the majority of their time being logged in a simulator. This makes increasing readiness – something GSC aims to do – potentially costly for the B-2.

Speaking at the Air Force Association’s symposium in Washington on September 17, General Timothy Ray, Commander, Global Strike Command (GSC), said Secretary of Defense, James Mattis had said to him: “If this was the last week of peace, what would you be doing differently today, to give an edge to what you are doing?” Having the resources to be able to answer this question effectively will be vital to the continued operational viability of the B-2 force until it is replaced by B-21 Raiders.

Contributing to its high per-hour cost of operations is the small size of the B-2 force, and the difficulty of sourcing needed parts from the findustrial base has made sustaining the B-2 challenging. In recent years, the B-2 fleet has averaged about a 50% availability and a 35% mission capable rate, compared to some 80% and 60%, respectively, for the B-52H. A B-2 requires 27 maintenance hours for each flight hour, compared to 17 for a B-52H; when all required aircraft support activities (including those required by the B-2’s low-observable skin) are added in, the total is several times this benchmark figure. Describing the awareness of B-2 operating costs, General Ray said: “We need to modernise and do the right thing, but we cannot afford to present the most exquisite, expensive, options out there.”

The B-2 is normally kept as a silver bullet force, able to penetrate hostile airspace against the highest value targets, where it can accurately deliver conventional or, if required, nuclear weapons. Of the 20 B-2s, 19 are operational and 15 of these are combat coded.

When B-2s in overhaul or maintenance are taken into account, there are about 11 or 12 aircraft available at any time. That was the statistic the then Commander GSC, General Robin Rand, told the House Armed Services Committee on September 29, 2015.

The Air Force is well aware of the threat posed by evolving technologies to the B-2’s second-generation stealth capability. By the time the B-21 is available to replace the B-2, it is projected that its ability to penetrate Anti- Access/Area Denial (A2/AD) environments will have been reduced. This has led to the decision incorporated in the Bomber Vector and the FY2019 budget request to replace the B-2 with the B-21 in the 2030s, even though it will be capable of operating into the late 2050s. The B-2 was originally designed for a 20,000 flight-hour service life, but this has been extended to some 40,000 hours.

The Bomber Vector’s direction also represents a US Department of Defensewide realisation that the air defence system that a peer competitor is likely to be able to deploy against US airpower in the 2040 timeframe may be highly lethal. What, then, would be required in 2040 for the B-2 to be able to penetrate a target defended by surface-to-air missiles with a 600km (325 nautical miles) range: missile systems that are enabled kinetically by advances in propulsion and operationally by networked radars and sensors with extensive data-processing capabilities behind them? The Air Force’s Air Superiority 2030 Flight Plan concluded: “The Air Force’s projected force structure in 2030 is not capable of fighting and winning against this array of potential adversary capabilities.”

The difficulty with determining an answer to the question when considering the ever more challenging array of threats likely to be encountered in 2040 is one reason why the Air Force changed its mind about keeping the B-2 operational until the late 2050s.

Speaking at the Air Force Association’s symposium in Washington on September 17, General Ray said: “The Air Force has looked at A2/AD threats much closer recently.”

Upgrades

The Air Force has already started to cut back upgrade programmes it had planned for the B-2, which raised concerns in the Senate, which, in the FY2019 National Defense Authorization Act, called on the Air Force to submit a report on B-2 modernisation, focusing on capability and capacity gaps in the near to mid-term.

The B-2’s major upgrade remains the defensive management system modernisation (DMS-M) programme, intended to improve threat radar detection, identification and avoidance capabilities, including a dynamic in-flight mission replanning capability. Ray stressed: “Continuing with DMS for B-2 is critical to keep on track.”

Northrop Grumman is prime contractor and integrator, with BAE Systems developing the digital electronic support measures (ESM) receivers, Ball Aerospace and L-3 Randtron providing the ESM antennas and Lockheed Martin supplying display processors. Assistant Secretary of the Air Force for acquisition, Dr William Roper, told the HASC on March 14, 2018, that the DMS-M is meant to ensure the B-2 maintains its ability to go into the most denied spaces of the world and be able to do its power projection mission.

Currently being tested, the DMS-M will go through an Air Force Operational Test and Evaluation Center operational assessment and initial operational testing evaluation. Any change to the B-2 – such as new antennas – has to be carefully tested to ensure it does not compromise stealth characteristics. Initial operational capability had been planned for 2022–2023, but now appears likely to be delayed to 2024. Cost of the programme, previously estimated at $2.7 billion, has been revised upwards to $3.1 billion.

In the FY2019 budget request, the Air Force cancelled a major B-2 upgrade; the advanced extremely high-frequency satellite communications programme would have provided two-way high-speed connectivity, but it would not have equipped the B-2 until 2026-2028, when the B-21 would be entering service. Instead, the FY2019 budget request included money for an alternative, focused on assuring connectivity for nuclear command and control without compromising stealth characteristics. Lt Gen J D Harris, Deputy Chief of Staff for Strategic Plans and Requirements, told the HASC on March 14: “The first one we’re looking at is an LF-VLF [low-frequency/very-low-frequency] system that will deliver before [2026–2028] and actually provide capability that we’ve been missing for a while.” The Senate Armed Services Committee was not convinced the Air Force’s decisions on the future of B-2 communications upgrades, and called on the Air Force to provide “estimated modernisation costs and timelines, consider opportunities to exploit capabilities developed for other programmes, and take into account timelines for introduction of future systems that will provide similar capabilities”.

An offensive system upgrade for the B-2 that was funded (to the tune of $43 million) for the first time in FY2019 is the radar-aided targeting system or RATS software upgrade, a programme that Roper called “an important part of the modernisation effort to make sure the B-2 maintains its penetration capabilities, communication capabilities and sensing capabilities in the future”.

Operations

The B-2’s speciality is accurately delivering bombs on high-value targets since Operation Allied Force during the Kosovo conflict on March 24, 1999. Though on a mission flown on May 7-8, five JDAMs struck the Chinese embassy in Belgrade. After flying combat operations against targets in Afghanistan, Iraq and Libya, in 2011–2017, B-2s flew no combat missions. This changed with Operation Odyssey Dawn, when a strike was flown against a terrorist camp in Libya on January 17–18, 2017. The target was bombed by two B-2s from Whiteman. A third B-2 took off with them, accompanying them as an air spare, before turning for home. Two ground spare B-2s were held on readiness as back-ups.

A B-2 Spirit taxis back to parking at Andersen Air Force Base, Guam.
TSgt Andy Kin/US Air Force

The two strikers, radio call signs Clip 11 and Clip 12 flew through international airspace until turning to hit their target near Sirte. The two B-2s hit their allocated target through a light overcast cloud cover at midnight local time. A total of 85 JDAMs were used, all 500lb class weapons. The JDAMs impacted, together, in under a minute. No other aircraft could have delivered so many guided munitions simultaneously to a target while retaining the element of surprise. The aircraft returned to Whiteman at the end of a 33- hour round-trip. Each of the three B-2s refuelled five times.

According to Commander, US Air Forces in Europe and Commander, US Air Forces Africa, General Tod D Wolters, this precision strike demonstrated that the US Air Force can put any target at risk, plus or minus a second, plus or minus a millimetre. Unstated, the mission also showed potential threats worldwide of what global delivery of precision firepower looks like.

The value of bomber deployments to enable the United States to demonstrate its continued commitment and resolve to coalition partners and potential aggressors alike was demonstrated in the three-aircraft B-2 deployment to Andersen Air Force Base on Guam in January 2018, joining B-1Bs already deployed there. This followed a single B-2 training deployment to Guam in October 2017.

B-2s have been deploying to Guam – where typhoon-proof hangars were built for them in 2005 – as part of GSC’s commitment to provide a continuous bomber capability in the Western Pacific. The number and type of bombers deployed vary to meet operational needs and the international situation. The August 2016 deployment, for example, represented the first time detachments of all three GSC bomber types were together on Guam for exercises and training and carrying out presence flights. Speaking at the Air Force Association symposium in Washington on September 19, Commander Pacific Forces, General Charles Brown said: “These missions provide the B-2 crews a chance to operationally integrate with our partners and with naval assets …We are able to do some things to incorporate Hawaii-based bombers.”

In 2017, all three GSC bomber types deployed to operate in Europe simultaneously for the first time. At RAF Fairford, in June two B-2s joined three B-52Hs from Barksdale and thee B-1Bs from Ellsworth to participate in the BALTOPS and Saber Strike exercises. The B-2 also made a public appearance at the Royal International Air Tattoo at Fairford. In addition to these deployments, B-2s have taken part in a number of exercises, including Red Flag, Northern Edge and Mobility Guardian. In April 2018, no fewer than 10 B-2s reportedly took part in the annual Neptune Falcon readiness exercise in the continental US, launching from Whiteman and refuelling twice from KC-10A tankers to strike simulated targets on the Tonopah ranges in Nevada. Two B-2s staged through Hickam Air Force Base, Hawaii, to take part in Exercise Valiant Shield 2018 on Guam in September, with one B-2 practising an enginesrunning hot-pit refuelling on Wake Island.

B-2 88-0329 ‘ Spirit of Missouri’, the flagship of the Missouri Air National Guard’s 131st Bomb Wing, returns from a training mission, at Whiteman Air Force Base, Missouri.
SMSgt Mary-Dale Amison

B-2 Spirit units

Air Force Global Strike Command

509th Bomb Wing, Whiteman AFB, Missouri

13th Bomb Squadron

393rd Bomb Squadron

394th Bomb Squadron was disbanded in April 2018

Air National Guard

131st Bomb Wing, Whiteman AFB, Missouri

110th Bomb Squadron, both associate units

Air Combat Command

53rd Wing, Eglin AFB, Florida

72nd Test and Evaluation Squadron, based at Whiteman

57th Wing, Nellis AFB, Nevada

325th Weapons Squadron, based at Whiteman

Air Force Materiel Command

412th Test Wing, Edwards AFB, California

419th Flight Test Squadron

Weapons

The B-2 is the only long-range strike aircraft capable of penetrating and surviving today’s advanced integrated air defence systems to deliver weapons against heavily defended targets. Many of these are hardened or deeply buried.

The B-2 is the only bomber able to carry two 30,000lb Boeing GBU-57A/B Massive Ordnance Penetrator (MOP) weapons, the largest conventional bomb. The production order for the MOP was placed in February 2018 and deliveries will be completed by July 2020. The B-2 will be modified to carry up to 192 Boeing GBU-39/Raytheon GBU-53 Small Diameter Bombs and up to 16 JASSM-ER missiles among its armament options.

Currently, the B-2 is the only one of the three bomber types capable of delivering nuclear gravity bombs, using the megatonclass B83-1 and the earth-penetrating B61-11 (a B-2 could carry up to eight of these). It is being upgraded to enable it to carry the improved B61-12, designed to defeat deeply buried targets. Production of the B61-12 is planned to start in 2020. It has already carried out flight-testing on B-2s, with two unarmed weapons being dropped from an Edwards-based B-2 at the Tonopah range in June 2018.