Fault tolerant electrical starting of gas-turbine engine

An airframe comprising:

• a first gas-turbine engine of a plurality of gas-turbine engines that are configured to propel an aircraft, the first gas-turbine engine comprising:
• a first electric starter of a plurality of electric starters, the first electric starter configured to rotate a spool of the first gas-turbine engine, wherein the first electric starter is rotationally connected to the spool of the first gas-turbine engine without a clutch;
• a second gas-turbine engine of the plurality of gas-turbine engines, the second gas-turbine engine comprising:
• a second electric starter of the plurality of electric starters, the second electric starter configured to rotate a spool of the second gas-turbine engine, wherein the second electric starter is rotationally connected to the spool of the second gas-turbine engine without a clutch;
• one or more controllers configured to control the plurality of gas-turbine engines;
• and
• a common electric starter controller configured to control the plurality of electric starters, wherein the common electric starter controller includes a plurality of switches configured to generate motor control power signals, output of which controls operation of the first electric starter and the second electric starter, wherein the motor control power signals comprise alternating current (AC) power signals, wherein the common electric starter controller is configured to mitigate a fault in one or more of the plurality of electric starters wherein the system further comprises:
• a multiplexor configured to route, at a particular time, the motor control power signals from the plurality of switches to either the first electric starter for starting the first gas-turbine engine or the second electric starter for starting the second gas-turbine engine, wherein, to mitigate a fault in the first electric starter, the common electric starter controller is configured to:
• cause the multiplexor to connect the plurality of switches to the first electric starter;
• and
• cause one or more of the plurality of switches to close.

A system comprising:

• a first gas-turbine engine of a plurality of gas-turbine engines that are configured to propel an aircraft, the first gas-turbine engine comprising:
• a first electric starter of a plurality of electric starters, the first electric starter configured to rotate a spool of the first gas-turbine engine, wherein the first electric starter is rotationally connected to the spool of the first gas-turbine engine without a clutch;
• a second gas-turbine engine of the plurality of gas-turbine engines, the second gas-turbine engine comprising:
• a second electric starter of the plurality of electric starters, the second electric starter configured to rotate a spool of the second gas-turbine engine, wherein the second electric starter is rotationally connected to the spool of the second gas-turbine engine without a clutch;
• one or more controllers configured to control the plurality of gas-turbine engines;
• a common electric starter controller configured to control the plurality of electric starters, wherein the common electric starter controller includes a plurality of switches configured to generate motor control power signals, output of which controls operation of the first electric starter and the second electric starter;
• and
• a multiplexor configured to route, at a particular time, the motor control power signals from the plurality of switches to either the first electric starter for starting the first gas-turbine engine or the second electric starter for starting the second gas-turbine engine, wherein:
• the common electric starter controller is configured to mitigate a fault in one or more of the plurality of electric starters, to mitigate a fault in the first electric starter, the common electric starter controller is configured to:
• cause the multiplexor to connect the plurality of switches to the first electric starter;
• and
• cause one or more of the plurality of switches to close, and
• the motor control power signals are over 10 kilowatts (kW).