There were search-and-destroy choppers looking for drug busts.

--- Does "search and destroy" is a name of a motorbike or does it just describe the type of guys who were riding them and looking for drugs? Wait, maybe it says that in the air there were helicopters, police helicopters looking for drug dealers and these helicopters are called "search and destroy" because they search for drug dealers and destroy them?????
That phrase usually describes a type of mission, as opposed to search and apprehend or search and rescue.
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So it has nothing to do with either helicopters or motorcycles?

So, does this sentence just say that police officers were attempting to catch guys trafficking in drugs. Hmm, so what is the "chopper" then?
I don't know the context, but I assume that choppers here means helicopters with a search and destroy mission.
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