How could it be effective in the early jet age?
The Po-2 was a night raider, coupled with its very slow speed and since it was made mostly of wood and fabric, returned a very small radar profile that made it difficult for radars to detect it. It was the second most used airplane for the Communist side, only the MiG 15 was used more. When looking at all the Communist planes used, not only was it the 2nd most used Communist aircraft like I already mentioned, it was also the 2nd most effective airplane used by the Communists.
The most successful bombing raid by North Korean forces was on June 15, 1953 with Po-2s, Yak-18s and La-11s bombed and completely destroyed the fuel dump (5.5 million gallons) at Inchon.
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