The B-52 Looks Set To Become The USAF's Hypersonic Weapons Truck Of Choice

The rise of hypersonic weapons gives the bombers a new and highly critical mission that no other U.S. combat aircraft is as well suited to perform.

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Though the U.S. Air Force plans to keep its B-52H Stratofortresses in front line service through at least 2050, its clear that the aircraft are becoming more vulnerable to increasingly advanced air defense networks and would have to rely heavily on long-range stand-off weapons during any potential high-end conflict. At the same time, the iconic bombers look set to get a new lease on life as the service’s principle platform for a slew of air-launched hypersonic weapons, a role that they are better suited to fill than any other existing American combat aircraft.

Earlier in August 2018, U.S. Air Force Colonel Lance Reynolds, the Program Manager for B-1 and B-52 Systems, briefed industry representatives on the status of both bombers during a meeting at Tinker Air Force Base in Oklahoma. The B-1 and B-52 Systems division is part of the Air Force Life Cycle Management Center’s Bomber Development Branch, which is located at Wright-Patterson Air Force Base in Ohio.

Reynolds’ presentation says that between the 2016 and 2022 fiscal years, the Air Force will conduct demonstrations of no less than seven different weapon systems, including various nuclear-capable strategic types, on the B-52, also known affectionately as the BUFF, for Big Ugly Fat Fellow. Of these, four are in-development hypersonic weapons. Broadly speaking, hypersonic weapons encompass unpowered and powered vehicles that fly at more than five times the speed of sound, or Mach 5.

The Air Force plans to test the Tactical Boost Glide (TBG) vehicle, which the service has been working together on with the Defense Advanced Research Projects Agency (DARPA), on the B-52 first. In its budget request for the 2019 fiscal year, DARPA said that it was planning to conduct the first flight test of the TBG some time in that time frame, which begins on Oct. 1, 2018, and ends on Sept. 30, 2019. The goal is to have an operationally representative prototype by 2023.

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A slide from US Air Force Colonel Lance Reynolds' briefing showing various B-52H-related developments and potential future upgrades as of July 2018.

In development since 2014, the TBG is unpowered and will use a rocket booster to accelerate the vehicle to both a high speed and altitude. It will then come screaming back down toward its target at approximately Mach 20. For this to work, the weapon will need to get the boost glide vehicle at least near the edge of space, if not briefly put it into orbit, and the final design could turn out to be an air-launched ballistic missile or something very similar in concept.

The Air Force is also working with DARPA on an air-breathing hypersonic missile known as the Hypersonic Air-breathing Weapon Concept (HAWC). A flight test demonstration of that weapon on the B-52 is supposed to occur before the end of the 2020 fiscal year, according to Colonel Reynolds’ briefing. HAWC will use a rocket booster to get the missile up to speed, at which point an air-breathing high-speed scramjet engine will take over, keeping the vehicle going at between Mach 5 and 10.  

The video below from Lockheed Martin in 2015 shows concept art for the TBG vehicle at around the 3:38 mark in the runtime.

It’s not clear if either TBG or HAWC, collectively referred to as the High Speed Strike Weapon (HSSW) program, will ever lead to operational weapons or if these designs will serve more a test beds for further developments. The Air Force already plans to leverage work on the TBG project to support its own Air-launched Rapid Response Weapon, or ARRW, which is pronounced “arrow.” 

Lockheed Martin has also been leading the work on both the TBG and HAWC. That same company has, unsurprisingly now secured the contracts to develop both the ARRW and a new air-breathing design called the Hypersonic Conventional Strike Weapon, or HCSW, which you’re supposed to pronounce as “hacksaw.”

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A slide from a separate US Air Force briefing in 2017 describing the High Speed Strike Weapon program, which encompasses the Tactical Boost Glide and Hypersonic Air-breathing Weapon Concept efforts.

ARRW, which has also now received the designation AGM-183A, will be an unpowered, air-launched boost glide type vehicle with the same basic characteristics as the TGB. The Air Force hopes ARRW’s first flight will occur in 2021.

That same year, the service wants a conduct the first test launch of the HCSW. As with TBG and ARRW, the limited publicly available information about this vehicle’s characteristics describes a system that is very similar to HAWC.

Though HCSW’s name implies that it will be conventional, it is possible that ARRW may be nuclear-capable. Colonel Reynolds’ presentation mentioned work on integrating a “special weapon” – a long-standing euphemism for nuclear weapons – onto the B-52 between Fiscal Year 2016 and 2021.

This could also be a reference to the more traditional Long Range Stand Off (LRSO) cruise missile, which will be able to carry a nuclear warhead. You can read all about that new weapon here.

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An underwing pylon loaded with AGM-86 air-launched cruise missiles sits in front of a B-52H bomber. The Air Force expects the LRSO will replace the AGM-86 when it enters service.

Even just adding the ARRW and HCSW to the B-52's arsenal would be significant developments. We at The War Zone have explored in depth why hypersonic weapons are so important on multiple occasions in the past. These vehicles have raw speed and inter atmospheric flight profiles that alone make them largely immune to enemy defenses.

A weapon system that flies at a mile per second across a distance of 1,000 miles significantly reduces the time in the kill chain from when the U.S. military identifies the target to when it actually strikes it. For an opponent, this translates to a far shorter amount of time in which to spot the incoming threat and decide to either try and shoot it down or evacuate critical assets and personnel from a particular site. Nuclear- or conventionally-armed hypersonic vehicles therefore offer a game-changing option for conducting strikes with little warning against time-sensitive and other critical targets.

The extreme speed and range of hypersonic weapons also makes them especially applicable to non-stealthy launch platforms, such as the B-52s, since it would allow the bombers to remain far away from enemy air defenses when launching the weapons. In addition, the BUFF already has an established capability to carry oversize payloads over long ranges and each bomber, depending on the size of the Air Force's future ARRW and HCSW designs, could offer a significantly greater volume of fire over other available launch platforms.  

The B-52s could potentially hit targets deeper inside hostile territory by flying right to the edge of those defensive networks, as well. Bombers in general also offer the added flexibility of being able to remain on airborne alert near a certain region, acting as a potential deterrent to an outright conflict, and are easier to recall if necessary to de-escalate a situation. This also helps explain why the Air Force plans to keep the BUFFs in service until 2050, even as the service plans to retire the B-1 bomber and continues procurement of the B-21 Raider stealth bomber

Combined with new fuel-efficient engines and other upgrades to the B-52’s conventional weapon and data sharing capabilities, sensors and defense systems, will be an especially cost effective launch platform for deploying these weapons. This may also explain why the service is looking to buy all-new under wing pylons for the BUFFs that can carry individual payloads weighing up to 20,000 pounds. It has already used B-52s to test various experimental hypersonic vehicles in the past, as has NASA.

An upgraded B-52J would probably be one of, if not the best possible choice for the hypersonics mission, while still retaining the ability to readily perform other conventional and strategic roles as necessary. Of course, the bombers will just be one part of the hypersonic weapon picture, as the U.S. military as a whole is looking to increase its capabilities in this regard in the face of similar developments in both Russia and China, the United States’ most likely near-peer opponents. 

Earlier in August 2018, China announced that it had successfully test launched a new, air-breathing hypersonic vehicle, called the Starry Sky 2, which reportedly reached a top speed of approximately Mach 6. This vehicle uses its own supersonic shockwaves to generate lift and stay airborne and is similar sounding, at least conceptually, to the U.S. Air Force’s X-51A Waverider.

In March 2018, Russia said that it was suspending work on a new intercontinental ballistic missile to focus on developing its Avangard nuclear-capable hypersonic boost glide vehicle. The Kremlin has already put the Kinzhal, an air-launched variant of its Iskander quasi-ballistic missile, into service and claims that it is capable of hypersonic speeds.

Colonel Reynolds’ industry day briefing also noted the continued work on the Miniature Air-Launched Decoy-X (MALD-X), which the U.S. Air Force and Navy are working on together under the auspices of the Pentagon’s secretive Strategic Capabilities Office.

MALD-X isn’t a kinetic weapon, at least not yet, but is instead capable of launching electronic warfare attacks against hostile air defenses and otherwise confusing them. That program recently finished up a flight test program and you can read about that novel air-launched system in more detail here.

Existing and future upgrade programs already looked set to ensure the B-52 would continue to be an important tool for the U.S. military in number of different capacities. Adding weapons such as ARRW and HCSW to the mix will make the bombers indispensable in future conflicts, especially as this hypersonics continue to take center stage.

Contact the author: jtrevithickpr@gmail.com