DIGITAL AIR DATA SYSTEM
The DADS consists of systems that detect and
measure raw flight environmental data for use
within the flight data computers. The follow-
ing systems perform these functions.
• Pitot-static system
• Air data system
• Standby flight instruments
Pitot-Static System
The pitot-static system (Figure 16-24) pro-
vides pitot and static pressure data to the DADC
1, DADC 2, and the standby pneumatic airspeed
indicator. The static system provides pressure
data to the standby pneumatic altimeter, the
stall protect system, and the cabin differential
pressure indicator. Two pitot-static heads and
two alternate static ports provide the pitot-
static pressure. All of the pitot-static heads
and static ports have anti-icing provisions.
The pitot-static system consists of the fol-
lowing:
• Pitot-static heads
• Alternate static ports
• STATIC PRESSURE selector valve
• STALL PROTECT static pressure se-
lector valve
• Standby instruments pitot and static se-
lector valves
• Total-air-temperature (TAT) probe
The pitot and static pressures flow through
tubing, flexible hoses, and manifolds. Two
guarded switches on each pilots side console
control the flow of pitot-static pressures. The
STATIC PRESSURE selector valves control
the DADC static pressure flow, and the STALL
PROTECT selector valves control the stall
protection system pressure flow.
The pitot-static pressures for both the standby
pneumatic airspeed indicator and altimeter
flow through two guarded standby instruments
pitot-static selector valves on the copilot’s
side panel. The TAT sensor probe provides
temperature sensing for the DADCs. The air
data system (ADS) heater control panel con-
trols the ADS anti-icing.
Pitot-static Heads
Both pitot-static heads (Figure 16-25) con-
sist of three pressure sensors within a probe.
Ram-air pressure sensors correspond to the
pilot side as P1 and the copilot side as P2.
Two static pressure sensors (S1 and S2) cor-
respond to both pitot-static heads. The S1 and
S2 sensors cross-couple with the opposite
head, S1 to S1 and S2 to S2.
The pilot-side pitot-static head supplies P1
pitot pressure to DADC 1. The copilot-side
pitot-static head supplies P2 pitot pressure to
DADC 2. A heater element in each pitot head
provides anti-icing. A PITOT HEAT fail an-
nunciator is located on each instrument panel.
Excess water drains through a hole in each
pitot head and into drain taps in the lowest part
of each pitot line.
Alternate Static Ports
Two alternate static ports provide static pres-
sure (S3) to the changeover manifold through
tubing. Each tube line vents to the atmosphere
through static-port holes. Tube lines connect
the manifold to the static source selector valves
and the cabin differential pressure indicator.
A heater element in each static port provides
anti-icing functions.
STATIC PRESSURE Selector Valves
With the STATIC PRESSURE selector valves
in the normal STATIC TUBE position, S1 and
S2 static ports provide static pressures for the
DADCs and SPS altitude transducers. Placing
either the pilot-side or copilot-side STATIC
P R E S S U R E s e l e c t o r t o A LT E R NAT E
SOURCE changes the DADC and SPS alti-
tude transducer static source from S1 and S2
CL 601-3A/R
16-27
FOR TRAINING PURPOSES ONLY
FlightSafety Canada
L t é e
L t d .
CL-600-2B16 PILOT TRAINING MANUAL