October 30: LEMON manuals on a temporary server, it is slow and having issues, download the manuals you need! Later in November we will switch back to the fast server.
High Altitude Compensation System: Operation
At high altitudes, the control valve is opened by the aneroid bellows of the HAC to allow air to bleed through the valve into the primary main well. At low altitudes, the control valve remains closed and no additional bleed air flows to main well.