AIM Block 13 Practice Test

Hot spots on the tail cone point to combustion-system problems, specifically issues with how fuel is delivered or how the chamber is burning the fuel. If the fuel nozzle isn’t spraying fuel correctly, or if the spray pattern is disrupted, certain areas can burn hotter than others, showing up as hot spots on the tail cone. Likewise, a faulty combustion chamber can produce uneven or incomplete combustion, creating localized overdrafts of heat that concentrate at the tail-cone region. That’s why the best choice is the one that acknowledges either problem—a malfunctioning fuel nozzle or a faulty combustion chamber—as potential causes. It captures the reality that hotspots can arise from issues in fuel delivery or in the burning process itself, rather than from a purely mechanical tail-cone fault. A loose tail cone is a mechanical condition that might lead to leaks or vibrations but doesn’t directly explain abnormal heat patterns in the combustion area. A worn turbine blade affects turbine-side operation and overall engine performance, but it’s not the primary reason hot spots would appear on the tail cone.