POWER PLANT
For Training Purposes Only
May 03
18-3
P I L O T T R A I N I N G G U I D E
Major Power Plant Components
N
1
Fan
The N
1
fan is a single-stage fan that consists of 28 titanium blades. A Kevlar blanket is
wrapped around the inlet housing to contain damage from a failed fan blade. The N
1
fan rpm is displayed on the EICAS primary page.
Variable Geometry (VG) Compressor
The VG system regulates airflow across the compressor by changing the position of
the compressor inlet guide vanes and the first five stages of the stator vanes. Fuel
metered by the Fuel Control Unit (FCU) is used to hydraulically change the vane
angle. The VG system optimizes the airflow’s angle of attack at the compressor blades
and provides compressor stall and surge protection.
Accessory Gearbox
The engine-mounted accessory gearbox is driven by the N
2
compressor. The gearbox
drives the:
•
engine lubrication pumps
•
alternator that powers the N
1
Control Amplifier
•
engine-driven hydraulic pump (Hydraulic Pump 1A or 2A)
•
engine-driven fuel pump
•
integral drive AC generator (IDG)
Mounted on the gearbox is the air turbine starter (ATS).
The N
2
rpm is displayed on the EICAS primary page.
