Flight Map

It steers the route and holds you level at the altitude where you engaged it; you fly the throttle.

Press the game's autopilot key (Enter by default) or the cockpit autopilot button.

• With a route planned:
  • It steers your craft along the route: smooth turns and back onto the line if you drift.
  • It holds you level at the altitude where you engaged it. To climb or descend, pitch by hand. Let go and it holds the new altitude. It doesn't touch the throttle.
  • It hands control back at the final approach fix, where the straight-in final begins, with an on-screen message.
• Without a route: the key works exactly as in the normal game (wing leveling / altitude hold).
• Press the key again at any time to disengage. All controls are yours again at once.

A typical flight: climb to your cruising altitude, set the throttle, and press the autopilot key. It steers you along the route at that altitude. When it's time to descend, push the nose down yourself while it keeps steering, and let go at the new altitude.

The guidance panel shows the autopilot state:

• AP ROUTE with the held altitude (hold 8750 m; levelling off while it settles, alt: you while you pitch), how far you are off the line, and the target speed if you turned on Manage Throttle;
• AP APPROACH (Autoland only);
• a hint that the autopilot key will fly the route.

A small ring on the map shows where the autopilot is steering.

Details:

• Tracking. It steers to stay on the drawn line: it flies the bank each turn needs, corrects any drift off the line, and joins the line at no more than 30°.
• Holding level (Altitude Hold = Hold Level, the default). It flies the elevator itself to keep you at the altitude where you engaged it, smoothly:
  • it damps out the slow up-and-down swing (phugoid) many crafts fly into hands-off, and finds the craft's trim by itself, so an untrimmed craft no longer climbs away;
  • corrections are gentle: at most 2–6 m/s up or down (more at higher speed), eased in at about 0.15 g, and its gains adapt to speed and air density, so it isn't twitchy at 400 m/s nor weak when slow;
  • if you engage while climbing or descending faster than 5 m/s, it first levels off smoothly, then holds the altitude where it levelled ("Autopilot: holding … m");
  • it never pulls the nose up near the stall.
• Changing altitude. Your stick works as normal while it's engaged, with no delay. While you pitch, it keeps only the trim it found. Let go, and it levels off and holds the altitude reached.
• Off (pilot only). Set Altitude Hold to Off (pilot only) to have it only steer: your pitch input (and trim) goes straight through, plus a little back pressure while it's banked in a turn.
• Can't hold level. If the craft needs more trim than the autopilot may use (e.g. a craft badly out of trim at full throttle), it says so on screen. Trim the craft or change the throttle.
• Throttle. Never touched by default. Turn on Manage Throttle to have it hold Cruise Speed (the planned speed by default) with slow, gentle throttle changes, never below Min Throttle.
• Bank angle. Never more than Max Bank Angle (30° by default). The rudder is left centred.
• Terrain (safety). With Terrain Avoidance on (the default), it checks the terrain under the route for the next ~25 s. If high ground would come within 100 m of your flight path, it climbs steadily (4–10 m/s) until there is 150 m again, then holds the new altitude, and the panel says terrain climb. Your own pitch input overrides it. It does nothing over the sea or with plenty of clearance. It doesn't use the game's AI terrain avoidance, which climbs to 2500 m above any land.
• Gear and VTOL. The gear key and the VTOL control stay yours while it's engaged.
• Ground. It doesn't engage on the ground: take off first.
• Hand-back. It also disengages if you clear the route, get into another craft, or the craft is badly damaged. If you plan a new route while it's engaged, it follows the new one. Every disengage is written to the BepInEx log with its reason (Route autopilot off: …).
• Leaving the seat. If you stand up (e.g. with Walkable Craft), it keeps steering and holding the altitude (with Off (pilot only), there is then no pitch input at all). Press the autopilot key to disengage.
• Multiplayer. It only ever flies your own craft, just like the game's own autopilot (see Multiplayer below).

Autoland (experimental, off by default)

With Autoland on, the autopilot doesn't hand back at the final fix. Instead it flies the final approach:

• down the glide slope (with the same smooth elevator control as the level hold) and centreline;
• landing gear down;
• with Manage Throttle on, slowing to the approach speed over the last 4 km before the fix.

On the route it holds the altitude you chose, so descend to about the final fix's height (shown next to it on the map) before you get there: pitch down, and let go at that height.

It hands back 15 m (50 ft) above the ground so you can flare and land yourself. It also hands back early ("unstable approach, go around") if it is well off the centreline or glide slope below 300 m.

It does not flare, touch down or brake for you. The game's AI landing mode is made for its own traffic: it only works on the game's built-in landing paths, doesn't control the player's throttle, and removes the craft once it has stopped. Every craft also needs different speeds, flaps and flare. So the last few metres stay with you.

The map keys do nothing while you type in the multiplayer chat (or any other text box), while a dialog is open, or while the dev console is open.

Keys can be rebound in the Gravy Mod Menu (Flight Map tab) or in the .cfg. The Flight Map tab also shows the current route, autopilot state and how many other crafts are on the map. Its Clear Saved Map button forgets the saved map, e.g. after moving an island in the Classic Islands settings. The map is then rebuilt from what loads.

Experimental online. This mod runs in multiplayer, but it still has bugs there that aren't fixed yet. It works best in single player for now.

Local only. Nothing is sent to other players, it works the same whether you host or join, and other players don't need the mod.

• Route autopilot: only ever flies your own craft, like the game's own autopilot, and only where the game allows its autopilot.
• Other players on the map: shown at any range by default, like the game's own air-to-air display. Other Players Range limits how far away they're shown, and Show Players hides them all.
• Air Traffic: its traffic only exists on your own computer, so the map shows your own traffic; other players' traffic isn't on your map.
• Brown Pearl marker: not shown when you join someone else's server, where the ship doesn't exist.

• Craft dependent. The autopilot steers with the ailerons and holds level with the elevators through the game's AI controls. Very unusual crafts (VTOLs, helicopters, crafts without normal control surfaces or with pitch on other controls) may wander. With Altitude Hold set to Off (pilot only), an untrimmed craft drifts up or down just as it would hands-off.
• Updating. Coming from a pre-release build, some settings are changed once to the new defaults, even if you had changed them: Altitude Hold is set to Hold Level, Manage Throttle and AutopilotDiagnostics are switched off. Change them back in the settings if you want. The old CruiseAltitude setting is removed from the file. A new install keeps the defaults and logs nothing about this.
• Far islands and memory. To put islands on the map before they load (Map Far Islands), the game's low-detail terrain for each one is loaded in the background, one at a time. The game keeps that terrain in memory until it next frees unused assets (e.g. when you leave the flight). It only happens once per island: the heights are saved with the map, so later flights skip them. Turn Map Far Islands off if memory is tight.
• Game updates. If a game update changes something the map reads from the game's internals, only that part switches off (with one line in the BepInEx log), e.g. reading far islands in advance. The map, runways, routes and the autopilot keep working.
• Airliner colour. Air Traffic airliners show in their own colour only on the machine running the traffic (the host); see Multiplayer above.
• Style change. Switching map style re-colours the map in the background. Nearby areas update first, and the rest follows over a few seconds.
• Easter egg markers. They follow the Cthulhu and Brown Pearl mods' settings within about 2 s. Those mods only add (or move) their easter egg on the next flight, so right after you switch one on or move it, the marker can show where it will be rather than where it is. The Brown Pearl marker is its patrol area, not the ship itself, and stays after the ship is sunk.
• Moved islands. If an island is moved, its old position stays on the saved map until you use Clear Saved Map.

• SimplePlanes 2 0.7.9
• BepInEx 5 (5.4.x, x64 Mono build) installed in the game folder. On Linux/Steam Deck with Proton, add WINEDLLOVERRIDES="winhttp=n,b" %command% to the game's launch options.

The Gravy Mod Menu is recommended: most mods keep their in-game settings and status there. Without it, edit the .cfg files in BepInEx/config/.