Airplane Flight Manual Supplement

190-00682-02 Rev. C Hawker Beechcraft C90A and C90GT King Air
Page 93 of 95
STATIC
The normal static system has two separate sources of static air, one source is connected to the pilot’s Air
Data Computer (ADC1), and the other source is connected to the copilot’s Air Data Computer (ADC2)
and the standby instruments. Each of the normal static air lines opens to the atmosphere through two
static air ports; one on each side of the aft fuselage; four ports total.
An alternate static air line is also provided for the pilot’s Air Data Computer (ADC1). In the event of a
failure of the pilot’s normal static air source (e.g., if ice accumulations should obstruct the static air ports),
the alternate source can be selected by lifting the spring-clip retainer off the PILOT’S EMERGENCY
STATIC AIR SOURCE valve handle, located on the right side panel, and moving the handle aft to the
ALTERNATE position. This will connect the alternate static air line to the pilot’s Air Data Computer
(ADC1). The alternate line is open to the unpressurized area just aft of the rear pressure bulkhead.
When the alternate static air source is not needed, ensure that PILOT’S EMERGENCY STATIC AIR
SOURCE valve handle is held in the forward (NORMAL) position by the spring-clip retainer.
The pilot’s airspeed and altimeter indications change when the alternate static air
source is in use. Refer to the Airspeed Calibration – Alternate System, and the
Altimeter Correction – Alternate System graphs in Section 5, PERFORMANCE, of
the airplane’s original Pilot’s Operation Handbook and FAA Approved Airplane
Flight Manual for operation when the alternate static air source is in use.
There are three drain petcocks for draining the static air lines located below the side panel on the right
sidewall behind an access cover. These drain petcocks should be opened to release any trapped
moisture at each inspection interval or after exposure to visible moisture on the ground, and must be
closed after draining.
Ground Communications
Ground communications is provided by the G1000 system by turning ON the airplane’s battery and the
Avionics Master switch. Com1 and the pilot’s audio panel will be powered. The pilot may use the
airplane’s speaker and hand microphone or a headset for communication.
WARNING