When we first arrived, during our briefing, we were told to ignore any loud thumps on the roofs of our dormitories and not go out and challenge anyone seen scuttling down as they may be SEALS performing HALO jumps.
In fact, during my time there, one unfortunate SEAL had a chute failure and deployed his auxiliary without having jettisoned the main chute, resulting in a streamer and leading to his death.
When I went to report what I had seen to the base brass, I was told it was a wind dummy. I got a little P.O.'d and told him that I had TS clearance and knew the difference between a wind dummy and a man waving his arms as he fell to his death.
ETA: I did my only sky diving at that base...given the course by the aforementioned three letter agency. Jumped from a Cessna 152 (as I recall) at 3000' AGL. (No tandem jumps, just ripcord.)
Funny thing, one of the other guys from my outfit who jumped a little later on, happened to land astraddle the only fence line in the general area. Ouch!
(He lived. His voice was a little higher, but he lived to take a great deal of abuse for years afterward.)
I also got to take off and fly a 152 while there...but never attempted a landing. I left that to those who knew what they were doing.
I spent a lot of time on Blackhawks during my career in South FL, occasionally being transported while on SRT ops out in the Everglades or west coast of FL...and also frequently when I worked out of our air wing / air smuggling group at Homestead AFB and worked alongside Bahamian officers on patrols.