Came across the linked article. The UH-60 appears to have had a number of crashes and lives lost between Y81 to 84: 15 crashes, 22 dead,and with two fatal in 40 days. Not sure how many of these were the crashes in Grenada in a formation landing. And this is now a revered (though old tech) helicopter.
On Grenada: Wake turbulence? Suck down? Some Sikorsky guy could answer.
As to what caused the grounding. In flight breakup: Tut-Tut!
TC
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