In mid-2021 the U.S. Airforce expanded its emergency operating capabilities by holding a training exercise on a state highway where two air force SOCOM (Special Operations Command) C-146A twin-turboprop transports and four reserve (National Guard) A-10s practiced landing and taking off from a stretch of highway. Both the C-146A and the A-10 were built for this sort of thing and during the Cold War the USAF joined other NATO air forces in practicing this sort of thing in Europe. This was the first time such training took place in the United States during peacetime. The air force is preparing to quickly send some combat and support aircraft to new hot spots emerging in Africa and other areas where speedy response with small numbers of aircraft could make a big difference.
This is the latest development in a two- decade effort to organize and train pilots and support personnel to deploy quickly to any part of the world and operate from small airports or, for some types of aircraft, roads. Since 2001 the air force tested these deployment capabilities for squadrons being sent overseas, with an emphasis on turning small civilian airports into bases capable of quacking providing air traffic control and support facilities for combat aircraft.
Given the increasing stockpiles of ballistic missiles with high-explosive warheads to quickly disable military airbases and major civilian airports, there has been a revival in training to use highways, especially in Asia where countries threatened by China note that China has the largest number of these ballistic missiles designed to take out air bases early in any war.
After testing the concept in 2015, India decided in 2016 to adopt the increasingly popular practice of training pilots and ground crews to use designated sections of highways as temporary air strips. North Korea has been a believer in this practice and regional neighbors Pakistan and China have also revived the use of highway airstrips.
In 2014 China held air force training exercises involving the use of designated stretches of highway for emergency airfields for fighters and transports. This technique had not been used by China since 1989 and by 2015 at least ten stretches of highway in Liaoning (adjacent to North Korea), Shandong (facing South Korea across the Yellow Sea) and Fujian (opposite Taiwan) provinces have been designated for such emergency use. There may be others that have been designated but not practiced on, so their location can be kept secret.
China is following the example of Taiwan which began regularly practicing using highways as emergency air strips for fighter aircraft back in the 1970s. Then that sort of thing was halted for 26 years as Taiwan tried to make peace with China. In 2004 the highway landings were resumed, and now it's done every few years. There is some preparation involved, at least for the peacetime drills. Troops walk down the length of highway to be used and remove any rocks or other objects that the aircraft wheels might hit. Then cars go down the road, honking their horns, to flush out any birds who might be sucked into the jet’s air intakes. At that point, the F-16s can come in and land. And then turn around and take off again. China apparently follows the same procedures as the Taiwanese.
When Taiwan resumed these drills in 2004 they included actual use of superhighways as secondary highway air fields for combat aircraft during military exercises. For example, in one publicized event two Mirage 2000 fighters landed on a highway, were serviced (which can include refueling, rearming or minor repairs) and took off again. Parts of Taiwan's system of superhighways were designed just for this purpose but actual use of the highways during training exercises lapsed for over two decades because the Defense Ministry did not want to block traffic or annoy China. The resumed training exercises on highways were done more for diplomatic reasons; to remind China that Taiwan had many defensive capabilities. In 2007, the highway drill was carried out once more, and again in 2011. With less warning these drills are still held, but without any publicity.