STUDENT GUIDE FOR T-1A AIRCRAFT SYSTEMS
311. ENGINE SYNCHRONIZATION SYSTEM
The engine synchronization system provides synchronization to either the fan or turbine
Revolutions per Minute (RPM) of both engines by electrically matching the RPMs. The left
throttle operates as the master and the right throttle serves as the slave. A control box determines
the error difference of the right slave and the left master RPM input and generates a command
signal input to the EFC. The EFC then sends a signal to the torque motor in the HMU to adjust
the fuel flow schedule of the right engine to synchronize the RPMs. The synchronization
actuators have a limited range of approximately 1.5% fan or turbine RPM.
The throttles are provided for thrust setting adjustment and fuel cutoff for the respective engine.
313. ENGINE INSTRUMENTS
Ten engine instruments using gauge displays with needle pointers are arranged in two adjacent
vertical rows on the center instrument panel. The left side represents the Number 1 engine; the
right side represents the Number 2 engine.
N1 (Fan RPM Indicator)
These indicators display percentage of engine fan speed from 0-110% RPM. The information is
provided in both digital and analogue format. The indicators receive RPM information from the
respective N1 speed sensor.
Inter-Turbine Temperature Indicator
These indicators display Inter-Turbine Temperature (ITT) and provide an average readout of the
ITT through six thermocouples. The numerical readings are interpreted in degrees Celsius (°C)
N2 (Turbine RPM Indicator)
These indicators display percentage of turbine speeds from 0-110% RPM. The information is
provided in both digital and analog format. They receive RPM information from the respective
N2 speed sensor installed on the accessory gearbox. The sensor reads off of the oil pump drive
Fuel Flow Indicators
The gauges indicate fuel flow in pounds per hour times 100.
Oil Pressure and Temperature Indicators
These gauges have a dual arc scale: one for oil pressure and one for oil temperature. The oil
pressure arc has a numerical range from 0-15 (x10), and indicates the pressure on the delivery