Relight of a propulsion system with a fuel cell

A propulsion system for an aircraft, the aircraft comprising an aircraft fuel supply, the propulsion system comprising:

• a fuel cell assembly comprising a fuel cell, the fuel cell defining an outlet positioned to remove output products from the fuel cell and a fuel cell assembly operating condition, wherein the fuel cell assembly further includes a dedicated fuel cell ignitor;
• a turbomachine comprising a compressor section, a combustion section, and a turbine section arranged in serial flow order, the combustion section configured to receive a flow of aviation fuel from the aircraft fuel supply and further configured to receive the output products from the fuel cell, the combustion section including a dome assembly, a combustion chamber, and a primary ignitor disposed downstream from the dome assembly, wherein the primary ignitor is disposed upstream from the dedicated fuel cell ignitor;
• and
• a controller comprising memory and one or more processors, the memory storing instructions that when executed by the one or more processors cause the propulsion system to perform operations including,
• receiving data indicative of a mid-flight flameout within the combustion section;
• modifying the fuel cell assembly operating condition in response to receiving data indicative of the mid-flight flameout within the combustion section;
• and
• initiating a relight of the combustion section, wherein initiating the relight of the combustion section comprises activating the dedicated fuel cell ignitor within the combustion chamber.