Bit,
No sweat, the S-76 has positive LSS across most of its envelope as measured by the dive till it hurts technique, but at aft CG it is slightly negative. The A had a pitch bias actuator to patch up that corner, and after a short while in service, the FAA agreed that the PBA was unnecessary and allowed it to be pulled. When the B came out, we folded the PBA algorithyms into its Sperry autopilot, and that took care of that. If no autopilot was fitted, then a PBA was required. The B is just like the A, but the people on the program at that time decided the PBA was a good thing, so they kept it.
All the while, the UK authorities resisted removing the PBA on all models. I have lost track of how that stands now.
I was the Chief Pilot on the S-76 in the beginning, and I challanged the FAA lead test pilot to allow a double blind flight eval, where the PBA was randomly switched off as he performed careful trimmed airspeed maneuvers. He refused, saying, "I couldn't tell, so why bother?"
So much for the sanctity of stick gradient requirements. I could discuss the fallacy of lat-dir gradients next, but my fingers are getting tired!
[ 07 September 2001: Message edited by: Nick Lappos ]