What occurs if there is a no light off condition in a jet engine?

In a jet engine, a "no light-off" condition refers to a failure of the engine to ignite fuel during the start process. This typically means that the fuel-air mixture is not reaching the required temperature or conditions necessary for combustion. If the engine does not ignite fuel during start, it cannot produce the thrust needed for operation, which leads to the engine being unable to engage in its intended function.

This situation could arise due to various reasons, such as insufficient fuel flow, improper aircraft procedures, issues with the ignition system, or unfavorable environmental conditions. When the engine fails to ignite, it remains in a non-operational state and cannot progress to the next stages of start-up. Understanding this process is essential for troubleshooting and ensuring safe aircraft operation.