The North Korean People’s Air Force is predominantly composed of Soviet jet designs from the 1950s, or at least their Chinese clones, plus a smaller number of aircraft from the 1970s and 1980s. However, the most numerous aircraft in North Korean service is even more antiquated: a single-engine biplane transport that first flew in 1947. North Korea operates over three hundred An-2 and Y-5 biplane transports in at least six regiments, and they play a key role in its military strategy.How could these chunky biplanes pose a threat to adversaries fielding guided missiles and supersonic stealth fighters? North Korea has...