What is a major advantage of using inertial navigation systems?

Inertial navigation systems (INS) are known for being self-contained, meaning they do not depend on external signals or references to determine the position, orientation, and velocity of a vehicle. This self-contained nature is a significant advantage, especially in environments where external signals may be unavailable or unreliable, such as in space, underwater, or during electronic warfare scenarios. Since these systems rely on internal sensors, like accelerometers and gyroscopes, they can continuously track movement and update the position without any emissions, making them covert and less susceptible to interception or disruption by enemy forces.

The other options inherently contrast with the strengths of inertial navigation systems. For instance, the systems are not easily jammed because they do not rely on external signals, and while they can provide accurate readings, accuracy can degrade over time without corrections from external references, highlighting the importance of periodic updates from other navigation aids.