Working in aviation probably puts you in a mindset that makes it harder to parse. It's not being used in a way that is related to flight or aircraft.

It's like if people were discussing where to have a conference, and one of them proposed a hotel. Then another person suggested a resort. Then a third person floated a cruise ship. Cruise ships do float, but it has nothing to do with anything. They are floating the idea of the ship as a venue.

Plenty of other HNers, myself included, don't work in aviation and still find this use of "landed" nonsensical.

Do you normally "float" a cruise ship though? A more apt analogy might be "dock". Maybe a news report says that a vacation company has broken some regulation so the government docked a cruise ship, meaning they took away a cruise ship like you would dock someone points. It's ambiguous at best.

You could float the idea of it, and you might also think that to float a ship means the process by which it is landed in the water when coming out of a dock?

I think the sentence is referring to aircraft that have been forced to land by the enemy, in contrast to "grounded" aircraft that had not taken flight.

I haven't worked in aviation so my understanding of terminology could be wrong, but either way it is definitely an unusual example.

"The enemy landed 4 of our aircraft" without context wouldn't generally mean "forced to land" imo (as a native speaker). It would mean that they either destroyed them or managed to acquire them.

For example I might say that "they landed 4 aircraft with their daring" if they forced us to abandon an air craft carrier (e.g. by sinking it) and then managed to steal 4 of the planes (before it sunk). Or I might say "they landed 4 aircraft with that bomb" if they dropped a bomb on an airfield and it destroyed 4 aircraft.

Right, I think you understand the word as I do: 'verb' + ed. "The enemy landed the jet" as in they forced the jet to land either directly or indirectly. This would mean that the two sentences use "landed" the same way. But my understanding is SuperGLUE's offical answer is that these use "landed" differently with the rational that "landed" is idiomatic and just means to procure or bring about (e.g. "I landed the job") and it happens to be used with planes.

A fishing boat can land a big catch - and a sales executive might have landed a big deal, perhaps after reeling them in or having them on the hook.

So this would be particularly apt wording if the enemy had thrown a net over the plane as it sank in the ocean.

But I prefer to think the enemy gifted british country estates to the planes.