Late last month, the US Department of Defense (DoD), the US Air Force and the US Missile Defense Agency (MDA) announced a plan to use F-35s to track and destroy enemy ballistic missiles during their rapid ascent – the “boost phase.”
This is an entirely new role for the F-35, and is not without controversy. So far, neither Japan nor South Korea, which both face a North Korean missile threat, and which both have orders in process for F35s, has commented.
The most expensive warplane ever, each F-35A costs more than US$89 million. The F-35B version, outfitted for vertical take-offs and landings, is even more expensive at more than $115 million per plane. And each F-35C, which can fly from aircraft carriers, costs more than $107 million.
“The F-35 Lightning II has a capable sensor system that can detect the infrared signature of a boosting missile,” stated the 2019 Missile Defense Review (MDR). “(An F-35) can be equipped with a new or modified interceptor capable of shooting down adversary ballistic missiles in their boost phase and could be surged rapidly to hotspots to strengthen US active defense capabilities and attack operations.”
In late January, Lt Gen Samuel Greaves, Director of the MDA, and others spoke about Japan’s important role in jointly developing new interceptors. Japan’s ability to deliver interceptors in general that tend to exceed rather than just meet specified performance criteria was highlighted.
Japan co-developed the SM-3 Block IIA interceptor with the US, which is just starting to be deployed. The MDA plans to test an SM-3 Block IIA missile against a ballistic missile target in 2020, according to the MDR, although it does not specify an F-35 as the launch platform for this test.
Still, critics of missile boost phase intercepts abound.
The Federation of American Scientists has consistently challenged the feasibility of boost-phase intercepts, in general, and views this attempt to use the F-35s for this purpose as faulty at best.
And for an aircraft to take down a missile in flight, there are multiple variables in play. According to Garren Mulloy, Associate Professor of International Relations at Japan’s Daito Bunka University in Saitama, these include radar capabilities, processor capabilities, network capabilities, aircraft endurance for loiter patrols, range to the loiter area, speed for emergency reactions and the number of and capabilities of missiles carried.
A potential game changer
Still, some experts are cautiously upbeat.
“This use of fighter and missile to take on ballistic missiles in the boost phase has been considered and tested in recent years,” Professor Narushige Michishita, director of the security and international studies program at the National Graduate Institute for Policy Studies in Tokyo, told Asia Times. “The F-15 has a better payload, but the F-35 has better information capability and stealth.”
If the concept is, indeed, feasible, there could be plentiful potential buyers of the capability in Northeast Asia, which brims with ballistic missile threats.
“If this technology and specific operational concept prove effective, that could have a significant impact on North Korea,” Narushige said.
“Air-launched boost-phase interceptors would certainly enhance deterrence capabilities against North Korea and China,” added Ryo Hinata-Yamaguchi, visiting professor at Pusan National University in South Korea. “[But] whether an F-35 can be truly effective in intercepting ballistic missiles at their boost-phase near or within the adversary’s proximity is questionable at this point.”
But the F-35 may not be the ideal aircraft for the role. “While the F-35’s network capabilities stand out, it is below par in most other areas,” Mulloy said, referring to the requirements noted above. “An F-15 or F-22 would be the best option.”
The ship-based F-35Bs which are expected to be assigned to Japan’s Izumo-class helicopter destroyers – which are undergoing feasibility studies for conversion to actual aircraft carriers – are even less suited. “The F-35B is the least capable version with the shortest range, least endurance, least payload capacity, and, is least capable in terms of speed and climb,” Mulloy said.
Budget, strategy constraints
Meanwhile, Japan’s defense budget is facing massive strains, given upcoming purchases.
By fiscal 2025, two Aegis Ashore ground-based missile interceptor systems will be installed in Japan at a cost of $2.5 billion. In addition, Japan has leapfrogged Israel to become Lockheed Martin’s largest global F-35 customer, after announcing it would be expanding its purchase from 42 to 147 F-35s.
“Japan’s defense budget is cash-based annual appropriations only. Even under the current proposed spending plan, Japan is facing budget difficulties,” said William Brooks, an adjunct professor at the Johns Hopkins University School of Advanced International Studies in Washington. “So there is a practical limit to Tokyo’s willingness to comply with Washington’s full-court press to buy expensive US aircraft and other military equipment.”
Japan’s new National Defense Program Guidelines serve as a further obstacle to effective missile defense.
An attempt last year to modify them to allow for an attack by Japan on enemy missile sites fell apart after the ruling Liberal Democratic Partys’s coalition partner, the Komeito, rejected the proposal.
“Under the guidelines, which look ahead for 10 years, the Self Defense Forces must focus solely on the defense of Japan and leave the role of attacking enemy bases to the US,” said Brooks. “If the North Korean missile threat to Japan is not diminished by the upcoming US[-North Korea] negotiations on nuclear and missile programs, Japan then would have to reconsider its current BMD capabilities to meet a saturation-attack scenario.”