Long-range stealth bombers are the most effective and least costly method for the US Air Force (USAF) to strike targets deep in China and Russia, according to a recent report by the Mitchell Institute.
The report, authored by former USAF bomber pilot Mark Gunzinger, stresses that the large number of target sets and deep interiors of the two potential rivals cannot be effectively addressed with expensive long-range, stand-off weapons such as cruise missiles.
The report also stresses that the USAF’s bomber mix is heavily weighted in favour of stand-off strike, given that it is dominated by the Boeing B-52 and B-1. Neither type would be able to penetrate the integrated air defence systems of the two rivals, it says.
The report also questions the ability of the existing USAF bomber inventory to mount sorties. It estimates that of the total bomber inventory of 141 aircraft, only 50 are mission capable at a given moment, allowing just 30 sorties per day.
“Long round-trip mission distances will stretch an already small bomber force to the absolute limit in terms of affording commanders with the combat results they require within operationally acceptable time lines,” says the report. “Failing to strike enemy targets in a rapid, full spectrum fashion will ultimately result in a far more costly, longer, and risk-prone campaign.”
It calls for a future force of at least 316 aircraft, the majority of which should be Northrop Grumman B-21 stealth bombers, due to enter service in the mid-2020s.
The report takes issue with the idea of using transport aircraft or, worse, developing a clean-sheet “arsenal plane” to deploy stand-off weapons. Noting the extensive work involved in developing the P-8A Poseidon from the Boeing 737, and the KC-46 from the 767, it believes modifying a civilian aircraft for the stand-off mission, or restarting the C-17 strategic transport line, would be costly and detract from the needed B-21 buys.
Beijing’s anti-access/area-denial (A2/AD) strategy, characterised by long-range surface-to-air missiles (SAMs) and increasingly advanced fighters, would force aircraft such as the B-52, B-1, and the notional arsenal plane to launch expensive weapons at least 400nm (741km) from China’s coast.
In addition to being expensive on a per unit basis, air-launched stand-off weapons cannot reach deep into China’s interior. The report contends that stand-off systems lack the ability to destroy hardened targets, such as deeply-buried bunkers, and are not as effective against highly mobile targets, such as SAM systems and other units that can be easily moved. In addition, China can push stand-off bombers further away by expanding its A2/AD zone.
“China, Russia, and other adversaries continue their long-term efforts to deploy advanced defences that are effective against US combat aircraft and weapons, improve the mobility of their forces to make them harder to target, build underground facilities that are protected by virtue of their depth and reinforced structures, and implement other measures to harden themselves against precision strikes,” says the report. “All of these actions could increase the time and number of weapons needed for US forces to defeat an enemy in future strike campaigns.”
The report calls for the USAF to focus on development of the B-21, which can conduct “stand-in” strikes at close range. It reasons that the B-21, despite a high cost per aircraft, offers better value in that it can deliver up to 80 relatively inexpensive smart bombs directly to targets deep in a rival’s land mass.
Stealth bombers that can operate in highly contested airspace also impose costs on rivals, forcing them to defend in greater depth and cover more directions of attack.
“The [Department of Defense’s] 1997 decision to stop buying stealth B-2s helped create a bomber force that is now too small, too old, and over-weighted toward stand-off aircraft,” says the report.
“While this force may have been adequate for past operations against lesser regional militaries, multiple analyses have concluded the air force should increase its capacity to conduct stand-in strikes in contested environments against peer adversaries. Doing so would require the USAF to buy at least 240 B-21 stealth bombers.”