ENGINE IAS MPH ALT FT HDG VSI FPM GND SPD GPS ALT ENDUR FUEL GAL 28 1180 --- 0 — — — 6.2 FPM 0 DEMO · SIMULATED ATTITUDE SVS TERRAIN LOADING 28 MPH IAS — 1180 FT ALTITUDE PHONE GNSS TRACK © OpenStreetMap ALERTS WIND ALOFT 245° / 9 MIXED SOURCE · NODE + PHONE PITCH / ROLL — POSITION — OAT 79°F BARO 29.92 DENS ALT —

Attitude source diagnostics

Modedemo flight
Secure context—
Running in iframe—
DeviceOrientationEvent—
Permission request—
Orientation events seen0
Generic Sensor API—
Geolocation—
Screen angle0°

Round-gauge landscape / portrait layout. Two circular instruments adapt automatically when you rotate the device. The left circle is the attitude indicator; the right (landscape) or lower (portrait) circle is the compass/HSI with a live OSM map tile layer underneath the rose. Climb rate (VSI) appears as a cyan bar inside the attitude indicator on its right side. Drag anywhere on the AI to fly by hand.

Map

Uses OpenStreetMap tiles at zoom 14 (~1.5 km radius around the aircraft). Tiles load automatically when a GPS fix is available or the demo flight is running. The map rotates heading-up: aircraft is always pointing at the lubber line. No tile requests are made when a position is unknown.

Speed arc

Red below stall (0–22 mph), green normal (22–38 mph), red above Vne (38–50 mph). White tick sweeps to current IAS. Values from the NODE PITOT channel — simulated here.

Altitude arc

Amber below 300 ft, green 300–2500 ft, amber above 2500 ft. Cyan tick sweeps to current altitude. Scale is 0–3000 ft. Values from the NODE PLENUM channel — simulated here.

Sensors

Device orientation fires only in a secure top-level context. Open this page as a standalone PWA or serve over HTTPS. The diagnostics panel above says exactly why sensors are or are not arriving.

Synthetic Vision (Terrain on AI)

Click Terrain (SVS) to enable. The attitude indicator overlays a terrain silhouette computed from AWS Terrarium elevation tiles (open data, no API key needed). Three hazard levels mirror real avionics conventions:

— Dark brown: terrain well below (safe).
— Amber: terrain close below — less than ~500 m clearance.
— Red: terrain above aircraft altitude — pull up.

The terrain rolls and pitches with the AI so canyon walls, ridgelines, and obstacles move correctly as the aircraft manoeuvres. Resolution is ~10 m/pixel at zoom 14; a canyon narrower than ~30 m will not be resolved — the same limitation real SVS has.

Tiles load on demand and are cached for the session. The green SVS badge confirms decoded data; TERRAIN LOADING means tiles are in flight. In demo mode the aircraft flies over flat Tennessee — try real GPS in hilly terrain for the dramatic version.

Layout mockup only. Not an instrument, not airworthy, not the Android client.