Linden Accident - Question about "Droop Lock"

I was talking to a Sikorsky pilot at our airport about this accident:
http://www.ntsb.gov/ntsb/brief.asp?e...26X01530&key=1

He said that Sikorskys have a "droop lock" in the cockpit that should
prevent the rotor from getting too low. How does this work? Does it leave
a certain amount of positive AOA in the blades so that they "fly" a bit
higher? I was curious.

Talking to my neighbor who runs a large helicopter concession on the Hudson,
and who keeps his ships at Linden (this was not one of his), the line boy
was very tall, and that presumably contributed to the accident. At any
rate, he's very lucky to be alive.

--
Bob (Chief Pilot, White Knuckle Airways)