Funny, that USAF missed a vessel armed with such a lethal ASM like SSN22 Sunburn.
:D
BTW correct pronunciation of "Lun" is closer to "Woon" (with short "oo") than "Loon".
Different sources state, that a massive thrust (and fuel consumption in a result) is necessary only for take-off and establishing WIG effect (air cushion). During WIG-flight ekranoplan uses less fuel. A90 Orlionok is a good example: it's propelled by turboprop engine - jet engines give drag only for
take-off, or flight at higher altitudes without WIG effect(like typical plane, which is also possible in case of "Lun" - hard to belive- up to 24000ft!).
Read this:
WIG
Of course, it doesn't change the fact that USSR-made jet-engines have higher fuel consumption than any comparable west-made.