Static pressure and pressure altimeter systems.

CFR · 2024-01-01 · US · Title 14

(a) Each instrument with static air case connections must be vented to the (b) Each vent must be located where its orifices are least affected by airflow variation, moisture, or foreign matter. (c) Each static pressure port must be designed and located in such manner that the correlation between air pressure in the static pressure system and true ambient atmospheric static pressure is not altered when the rotorcraft encounters icing conditions. An anti-icing means or an alternate source of static pressure may be used in showing compliance with this requirement. If the reading of the altimeter, when on the alternate static pressure system, differs from the reading of altimeter when on the primary static system by more than 50 feet, a correction card must be provided for the alternate static system. (d) Except for the vent into the atmosphere, each system must be airtight. (e) Each pressure altimeter must be approved and calibrated to indicate pressure altitude in a standard atmosphere with a minimum practicable calibration error when the corresponding static pressures are applied. (f) Each system must be designed and installed so that an error in indicated pressure altitude, at sea level, with a standard atmosphere, excluding instrument calibration error, does not result in an error of more than ±30 feet per 100 knots speed. However, the error need not be less than ±30 feet. (g) Except as provided in paragraph (h) of this section, if the static pressure system incorporates bot

official document · source cfr-2024 · id 14:§ 29.1325