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Tensions between Taiwan and China leads the former to develop cruise missiles out of old fighter jets’ engines. The J85 turbojet engines in question come from Northrop F-5E/F jets, called the Tiger II. Produced in the 1970s, the Tiger II was a low-cost multi-role jet in the same vein as today’s F-16. The F-5E/F had one engine, a General Electric J85-GE-21, a design that is still around: A variant of the J-85 powers the U.S. Air Force’s T-38 trainer, and another version will power Boom’s upcoming 50-passenger supersonic jet, according to popularmechanics.com.
Over the years, Taiwan bought or produced 308 Tiger IIs, including 242 single seat -E versions and 66 two seat -F versions. Now a report in the Taiwanese press states that Taiwan’s Chinese Academy of Sciences, in conjunction with the Republic of China Air Force, is pulling engines from decommissioned Tiger IIs with the hopes of producing a “simplified, improved” turbojet engine expected to go into a new missile to threaten China.
The J-85 engine is small, just over 17 inches wide and 45 inches long, and produces 3,000 pounds of thrust. The size makes it a good fit for a cruise missile. Indeed, during the Cold War the J-85 powered the ADM-20 Quail, a drone designed to mimic (and draw fire away from) B-52 bombers. The J-85-21 variant of the engine had the highest thrust-to-weight ratio of its time, 7.3 to 1, providing the F-5E/F with the power to reach speeds of up to Mach 1.6.
One way for Taiwan to prevent invasion is to hold targets on the mainland at risk. The Formosa Strait separating the two countries is only 110 miles long, so a cruise missile with a 300-mile range could strike targets more than 150 miles inside mainland China, threatening airfields, ports, command centers, and anything else that would support an invasion. A preemptive strike against such targets could disrupt, delay, or even cancel a cross-strait attack before it begins.
With evidence of a massing invasion force overwhelming, Taiwan would launch a barrage of cruise missiles against preset targets.