Hidden fire in an aircraft overhead inaccessible-area is hazardous to in-flight safety and could lead to catastrophic disaster. In this case, fire detection at the earliest stage requires an improved understanding of the heat and mass transfer in overhead areas with curved fuselage sections. In this effort, an experimental campaign was conducted at the FAA William J. Hughes Technical Center on different fire scenarios for the Boeing747-SP overhead inaccessible-area to advance knowledge on this phenomenon and provide validation data for the Fire Dynamics Simulator (FDS). Extensive work has been done recently to enable computer simulation of fire on complex geometries within this tool. Therefore, we use the experimental data obtained to perform validation of said capability. Model validation results are defined in terms of thermocouple readings measured and computed with satisfactory overall agreement.