This British Standard specifies the general design and performance requirements for pressure altimeter systems having a combined counter and single pointer presentation in two forms as follows.
(a) Type A. A panel-mounting indicator associated with its own internal or external pressure sensing mechanism.
(b) Type B. As type A but incorporating an encoder for altitude reporting purposes.
Provision is made for instrument systems operating over an indicated range of -2000 ft to +80 000 ft (geopotential) or such other range as may be declared.
The design includes a barometric pressure setting facility and may include provision for applying corrections for the aircraft static pressure system error.