This Aerospace Standard establishes the essential minimum safe performance standards for Pressure Actuated Compensated Altimeters, primarily for use with turbine powered subsonic transport aircraft, the operation of which may subject the instruments to the environmental conditions specified in paragraph 3.3. This Aerospace Standard covers two types of compensated altimeters which indicate, by visual means, the pressure altitude compensated for the static pressure system errors of the aircraft. TYPE I - Range: - 1,000 to 30,000 feet. Barometric pressure - scale range: at least 28.1 - 30.99 in. Hg (952-1049 millibars). May include markers working in conjunction with the Barometric Pressure Scale to indicate pressure altitude. TYPE II - Range: - 1,000 to 60,000 feet. Barometric pressure - scale range: at least 28.1 - 30.99 in. Hg (952-1049 millibars). May include markers working in conjunction with the Barometric Pressure Scale to indicate pressure altitude.