# Inertial Navigation System > [[PORTAL_Avionics|Avionics]] spine. ## Microsim — queued <p class="wt-pending"><strong>Microsim in the draft queue.</strong> Troy is building the interactive sim for this station by hand; the sourced physics below is complete and citable now.</p> ## Overview An inertial navigation system (INS) is a self-contained device that tracks position, orientation, and velocity using accelerometers to measure linear acceleration and gyroscopes — commonly a [[Fibre-optic_gyroscope|fibre-optic gyroscope]] or [[Ring_laser_gyroscope|ring laser gyroscope]] in modern designs — to measure rotational movement. Through dead reckoning, the system integrates these measurements with an initial position and velocity to continuously calculate updated location without requiring any external reference. In aviation, INS is a critical, jam-immune component of aircraft guidance, valuable for military and commercial aircraft alike; its principal weakness is integration drift, so modern aircraft typically fuse INS with GPS and other navigation aids to hold accuracy over long flights. **On the spine:** [[Radar]] · [[Autopilot]] · [[Fly-by-wire]] · [[Fibre-optic_gyroscope]] · [[Ring_laser_gyroscope]] · [[Aviation]] · [[Aircraft]]. <!-- FLIGHTSIM:BEGIN g22 — Aviation x Avionics microsim (framework build, specs/sims/Inertial_navigation_system.json); do not hand-edit inside --> **Microsim — three.js (Wikitube framework):** *Inertial navigation system* <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/flight/Inertial_navigation_system.html" data-title="Inertial navigation system"></div> *Built from `MICROSIM_GUIDE/specs/sims/Inertial_navigation_system.json`; part of the [[Aviation]] · [[Avionics]] flight set.* <!-- FLIGHTSIM:END --> <!-- FLIGHTLINK:BEGIN g23 — generated from _registry/plans/AVIATION_AVIONICS_SECTIONS.md; do not hand-edit inside --> **Part of the [[Avionics]] hub** — main article for section X9, *Inertial navigation*. Related sections: Pitot–static system · Global Positioning System · Flight instruments. <!-- FLIGHTLINK:END --> ## Wikipedia : Wikitube **Strict pair:** [Wikipedia](https://en.wikipedia.org/wiki/Inertial_navigation_system) : [Wikitube](https://en.wikitube.io/wiki/Inertial_navigation_system) --- *Repopulated 2026-08-05 · text transfer · 0 deletions.*