[Rockingham]

Soviet jet engines, turbines, and turbofans were notorious fuel guzzlers. The best case for the aircraft was as a fast troop transport and as a way to launch salvoes of guided missiles at US and NATO naval vessels when they were clustered in a carrier task force. I think that what eventually killed the project was that in addition to cost and limited value, the Soviets no doubt realized that the look down, shoot down radars being deployed by the US in the late 1980s would deprive the LUN of the element of surprise and make it exceptionally vulnerable.

[RayChuang88]

Actually, if they can design it around a ducted fan engine using a turboprop, you could make it work without the ridiculous fuel consumption and noise (which was the downside of the Soviet ekranoplan designs). Such a vehicle--"flying" maybe 150-175 passengers--would be perfect for trips between Busan in South Korea and Fukuoka in Japan (imagine travel in around one hour, compared to the circa 3.5 to 4 hour trip by hydrofoil now).