BOMBARDIER BD-100-1A10, Operating Manual

Page: 531 / 544

POWERPLANT
May 06/2005 Flight Crew Operating Manual Volume 2
REV 2 CSP 100-6
18-01-15
ENGINE STARTING SYSTEM (Cont)
COMPONENTS AND OPERATION
STARTER CONTROL VALVE
The starter control valve is mounted adjacent to the air turbine starter (ATS) inside the engine nacelle. The valve normally
requires 28 VDC power and pneumatic pressure to open. When the L (R) starter switch on the ENGINE control panel is
moved to the START position, the FADEC supplies 28 VDC power to energize the solenoid. This allows pneumatic pres-
sure to open the valve and engage the air turbine starter.
When N
2
rpm is > 50%, the FADEC removes power from the solenoid, the start valve closes and the air turbine starter
disengages.
AIR TURBINE STARTER (ATS)
The air turbine starter is mounted on the accessory gearbox. The ATS converts pneumatic energy into mechanical motion.
The starter, through a sprag clutch, mechanically engages the accessory gearbox and assists in accelerating the engine to
idle speed. During the start sequence, the start valve closes and the ATS disengages when the N
2
reaches or exceeds 46.2%
or the OFF position is selected on the throttle quadrant assembly panel.
For subsequent starts, the starter sprag clutch does not require that the engine rotation be completely stopped before engag-
ing the starter. The ATS may be engaged at any rpm up to 50% rpm (starter cutout speed).
START SEQUENCE
Each engine has a set of L (R) STARTER switches on the ENGINE control panel and a set of RUN/OFF switches on the
throttle quadrant panel.
To start the engines, set the related engine switch to RUN. This turns on the fuel DC boost pump and operates the ECU
start cycle. Set START switch to the START position and hold it for one second to operate the usual ground or air start.
When the applicable engine RUN position is selected on the TQA and the starter switch is set to START the:
- The start valve on the associated engine opens to allow pressure from the bleed air manifold to engage the ATS
When the engine’s N
2
reaches 46.25%, the:
- The start valve closes and the ATS disengages
If the start valve fails to close after achieving 50% N
2
, a L (R) STARTER FAIL ON (C) CAS message is shown
Refer to the Airplane Flight Manual for starter limits.
CFO1801002_015
START CRANK
OFF
CRANK
START
OFF
R ENGINE
OFF
RUN
L ENGINE
OFF
RUN