Reference

Specification / API

Understanding the data format and the API

To pull data from a third-party app or website you need a running SSC-Tracker app. SSC-Tracker acts as a proxy, so that the ssc-tracker.org server is not overloaded.

You can reach tracker data on the standard port 55055 on localhost. From another device on the local network, access is possible through http://[IP SIM PC]:55055. That requires LAN access to be enabled once (☰ → Connections → Enable LAN access, one admin dialog) - there is no need to run the app as administrator permanently.

If Windows blocks 55055, the tracker uses the first free fallback port of 45055-45058 for that session (☰ → Connections shows the port in use). The examples below use 55055; replace it with the port in use. To find the tracker from your own code, ask GET /version on 55055 and then on the fallbacks: the tracker answers {"version":"…","app":"SSC-Tracker","port":…}.

All endpoints answer over HTTP (HTTPS is not implemented at present). CORS headers are set, so websites can access them directly.

Overview of all endpoints

GET endpoints

POST endpoints

Fetching live aircraft data

GET http://localhost:55055/json

Returns the aircraft data of every pilot in the group. The values are updated every second. TSK values are only available while a task/flight plan is loaded.

Fields:

GN:              Group name
TASK:            Current task name
WEATHER:         Weather preset name
ID:              Your own pilot ID
ITEMS:           List of all pilots
  GN:            Group name of the pilot
  ID:            Pilot ID
  NAME:          Pilot name
  AC:            Aircraft name
  MODEL:         Aircraft model
  TH:            True heading [deg]
  LON:           Longitude [decimal]
  LAT:           Latitude [decimal]
  IAS:           Indicated airspeed [kn]
  TAS:           True airspeed [kn]
  GS:            Ground speed [kn]
  LV:            Last landing speed [kn]
  VS:            Vertical speed [ft/min]
  WD:            Wind direction [deg]
  WV:            Wind speed [kn]
  MSL:           Height above MSL [ft]
  AGL:           Height above ground [ft]
  TSK_TIME:      Task time since the start line [s]
  TSK_AVG:       Average speed, straight line [kn]
  TSK_AVG_PATH:  Average speed, path flown [kn]
  TSK_NEXT:      Name of the next waypoint
  TSK_DIS:       Remaining distance to the finish line [nm]
  TSK_DIS_PATH:  Distance flown along the path [nm]
  TSK_DIS_ALL:   Task distance flown [nm]
  TSK_DIS_WP:    Distance to the next waypoint [nm]
  TSK_ONGROUND:  1 = on the ground during the task
  TSK_SLEWT:     1 = slew mode during the task
  TSK_ENG:       1 = engine running during the task (soaring)
  DIS:           Distance from your own aircraft [nm]
  FLAPS:         Flap setting
  TW:            Total weight [lbs]
  VER:           App and MSFS version

Example:

{
    "GN": "ssc2",
    "TASK": "Bolzano Dolomiti SE",
    "WEATHER": "SSC2 08 Clear Sky SE 15kt",
    "ID": "FELTE",
    "ITEMS": [{
        "GN": "ssc2",
        "ID": "FELTE",
        "NAME": "Felte",
        "AC": "AS-33me",
        "MODEL": "AS-33me",
        "TH": 0.8,
        "LON": 11.531,
        "LAT": 46.462,
        "IAS": 85.0,
        "TAS": 90.0,
        "GS": 88.0,
        "VS": -1.2,
        "WD": 270.0,
        "WV": 12.5,
        "MSL": 6200.0,
        "AGL": 4800.0,
        "TSK_TIME": 1823.0,
        "TSK_AVG": 72.4,
        "TSK_NEXT": "TP1",
        "TSK_DIS": 45.2,
        "TSK_DIS_WP": 12.8,
        "TSK_ONGROUND": 0,
        "TSK_SLEWT": 0,
        "TSK_ENG": 0,
        "FLAPS": "1",
        "TW": 1208.0,
        "VER": "0.8.0.0|MSFS2020"
    }]
}

Fetching the Whazzup format (Little Navmap)

GET http://localhost:55055/

Returns the aircraft data in Whazzup v1 format, which Little Navmap and other tools support.

Fetching the active flight plan

GET http://localhost:55055/activetaskpln

Returns the active flight plan in MSFS PLN XML format, when a task is loaded.

Fetching the active task as JSON

GET http://localhost:55055/activetask

Returns the parsed task as JSON. The data contains all waypoints with coordinates, sector types and task progress.

{
    "Name": "Bolzano Dolomiti Airport",
    "GN": "ssc2",
    "DepartureID": "LIPB",
    "Distance": 173906.57,
    "IsEmpty": false,
    "IsStarted": false,
    "IsFinished": false,
    "IsAATTask": false,
    "StartWPIndex": 1,
    "FinishWPIndex": 4,
    "NextWPIndex": 1,
    "Waypoints": [...]
}

Elevation endpoints

The /elevation/… paths in the tables above: status, task profile, single point, user route, line and area.

User route

/userroute/load and /userroute/save read and write the route you drew in Preflight. It is stored as userroute.json in the task folder.

Setting a task locally (without uploading to the group)

POST http://localhost:55055/settask

Sets a task locally in the SSC-Tracker app without uploading it to the server.

Required fields: CMD, TASK, TASKDATA

{
    "CMD": "SET",
    "GN": "[GROUP NAME, optional]",
    "TASK": "[TASK NAME]",
    "TASKDATA": "[.PLN XML CONTENT]",
    "TASKINFO": "[URL or info text, optional]",
    "WEATHER": "[WEATHER PRESET NAME, optional]",
    "WEATHERDATA": "[.WPR XML CONTENT, optional]"
}

Endpoints have been added since the old edition. The full state of the local server (default port 55055):

All endpoints answer over HTTP with CORS headers set; there is no HTTPS.

Files and folders

The settings are a plain JSON file. You may edit it by hand - but only with the app closed, otherwise the next save overwrites the change. Identity (name, ID, group) and the logger sync are signed on top of that: if another program changes them, the tracker restores them at the next start.

Units

The display follows your settings (metric/imperial). Read the raw data through /json or /activetaskjson, however, and you get fixed units - and they are not the same everywhere: