What incident during a flight requires immediate reporting to the NTSB?

The requirement to report an in-flight fire that causes damage to the NTSB is grounded in safety and regulatory protocols. An in-flight fire is a critical incident that poses immediate danger to the aircraft and everyone on board. This type of emergency can lead to significant and potentially catastrophic outcomes if not managed appropriately. The NTSB (National Transportation Safety Board) plays a key role in investigating such serious incidents to determine the cause, contributing factors, and necessary safety recommendations to prevent future occurrences.

This reporting is essential not just for the specific incident at hand but also for the broader implications it might have on aviation safety regulations and practices. Hence, any incident involving fire and resulting damage requires prompt notification. Other incidents, while serious, do not carry the same urgency or potential for widespread implications as a fire that compromises safety.