C172S Instruments

Where are the pitot-static systems located

The pitot-static system uses a heated total pressure (pitot) head mounted on the lower surface of the left wing, external static port mounted on the left side of the forward fuselage and associated plumbing to connect the air data computer and the conventional pitotstatic instruments to the sources.

How does the pitot heat work

The heated pitot system uses an electrical heating element built in the body of the pitot head.

What is the purpose of the static pressure alternate source and where is it located

The ALT STATIC AIR valve provides static pressure from inside the cabin if the external static pressure source becomes blocked. It is located adjacent to the throttle

What is the air data computer (GDC) and where is it located

The Air Data Computer (ADC) compiles information from the airplane's pitot-static system. The ADC unit is mounted behind the instrument panel, just forward of the MFD. An outside air temperature probe, mounted on top of the cabin, is connected to the ADC.

What components are in the vacuum system

The vacuum necessary to operate the standby attitude indicator. The system consists of one engine-driven vacuum pump, a vacuum regulator, the standby attitude indicator, a vacuum system air filter, and a vacuum transducer.

How does the vacuum system operate

air is drawn into the vacuum system by the engine driven vacuum pump. it first goes through a filter, which prevents foreign matter from entering the vacuum pressure system. The air then moves through the attitude and heading indicators, where it causes the gyros to spin.

How is the attitude indicator powered and where is it located

The standby attitude indicator is a vacuum-powered gyroscopic instrument, found on the center instrument panel below the MFD

How does the OAT indicator work

The O.A.T. indicator uses an air temperature sensor located on top of the cabin.

What type is the stall warning and where is it located

Pneumatic-type with an air operated horn(upper left corner of the windshear, consisting of an inlet in the leading edge of the left wing

How does the stall warning work?

As the airplane approaches a stall, the low pressure on the upper surface of the wings moves forward around the leading edge of the wings. This low pressure creates a differential pressure in the stall warning system which draws air through the warning horn, resulting in an audible warning at 5 to 10 knots above stall in all flight conditions

What does the Attitude Heading Reference System (AHRS) do

The AHRS provides airplane attitude and flight characteristics information to the G1000 displays and to the integrated avionics units, which is located in the tailcone of the airplane.

What does the ADC do and where is it located

ADC compiles information from the pitot-static system to provide pressure altitude, IAS, TAS, VS and OAT. Its located behind the instrument panel, just forward of the MFD

How does the Attitude and Heading reference system provide information

The AHRS unit contains accelerometers (a device that measures the vibration, or acceleration of motion of a structure), tilt sensors and rate sensors that replace spinning mass gyros used in other airplanes. The magnetometer is located inside the left wing panel and interfaces with the AHRS to provide heading information.

What are the purpose of stall strips on the wing

Attached to the leading edge of the wing. At high AoA they disturb the airflow causing that section of the wing to stall first. Can be used to create a washout like effect on a straight wing.

What is the purpose of single slot wing flaps

Re-energises the airflow and delays seperation.

What are fowler flaps and the purpose of them

A split flap that slides rearwards level for a distance prior to hinging downwards. It increases chord and camber which increases lift

What is the purpose of frise ailerons

The aileron being raised pivots on an offset hinge. The leading edge of the aileron is now pushed into the airflow, creating drag and reducing adverse yaw. In this case, frise ailerons are using form drag to counter induced drag.

What is the purpose of differential ailerons

One aileron is raised a greater distance than the other aileron is lowered. Up going aileron produces more drag than the downward aileron. This produces an increase in drag on the descending wing, which reduces adverse yaw

What transponder do we have

Mode S providing mode A, C and S functions. Located in the tail cone

What does a mode s transponder do

Selectively responds to ground radar, provides precise altitude and ID data and enables modern collision avoidance (if traffic system installed)

What is the engine monitor?

AKA Engine/airframe unit, it compiles data from the engine to show to the pilot in the form of the EIS