From the MFEPD
ELECTRIC ENGINE START
Engine start for the 787 is no longer accomplished via pneumatic power. The 787 utilizes electrical engine start
and it is typically achieved via the APU Starter generator (ASG) which provides electrical power to the motor
controllers to operate the VFSGs as motors to start the main engines. A normal engine start can still be
accomplished with either a failed ASG or VFSG.
To achieve engine start during ground turn-around operations with the APU inoperative, it is recommended to
utilize a third additional 90 kVA, 115 Vac, 400 Hz source at the aft external power receptacle to preserve cabin
services during engine start and to shorten engine start time.
SINGLE SOURCE OPERATIONS
Minimal gate service can be accomplished with a single 90 kVA ground power source. Dependent upon the
number of galley carts being cooled; an externally conditioned air source may be required when ambient
temperature is above 80 degrees F.
DUAL SOURCE OPERATIONS
The dual-source configuration entails power applied to both of the forward co-located external power
receptacles (180 kVA maximum) or one forward and one aft receptacle (90 kVA maximum). This configuration
will allow for engine start with a temporary loss of up to 2 minutes for all functions with the exception of cabin
lighting.
THREE SOURCE OPERATIONS
Power applied to both of the forward co-located and to the aft external power receptacles is used for nonnormal
engine start (i.e. APU inoperative), non-routine maintenance activities and system troubleshooting.
This configuration will avoid cabin load shedding.
APU OPERATIVE
The APU operative scenario will allow for full cabin and cargo loading services during turn around including
normal engine start.