Here is another story from the archives. The US Navy version of the S-58 had an Automatic Stabilization System that included among other capabilities Barometric hold and Hydrodynamic hold, which was used during SONAR operations. The Barometric hold was installed in the upper right corner of the battery compartment. The unit was tied into a static port. The Navy constantly complained that rain water would collect in the lines and render the unit incapable of performing its’ function. Sikorsky in their wise ways disconnected the unit from the static port and the sensor line was connected inside of the helicopter. One day an HSS-1 was moving at about 30-40 knots and was preparing to stop and lower the SONAR ball. The Co pilot opened his sliding window, which made a dramatic change in the atmospheric pressure inside of the helicopter, and the sensor commanded the control system to lower the helicopter. The wheels were in the water before the pilot could disengage the Bar Alt sensor and raise the collective. Sikorsky eventually found a new location for the static port but before they did the Navy was told not to use the Bar Alt.
As an added note, the ASE was a very slightly modified autopilot used in the USAF F-86.
When the SONAR ball was lowered and the helicopter was in a hover an individual could move the sonar ball in any direction and the helicopter would follow. See the first photo on page two of this thread. If this were a HSS-1 and someone moved the ball in relation to the helicopter the helicopter would move in that direction. I do not know if the Wessex had this same capability.
[ 12 February 2002: Message edited by: Lu Zuckerman ]</p>