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+# XML Mission File Definition
+
+## Overview
+
+Historically, mission planners interoperating with inav (and multiwii) missions have used the XML mission file format defined by EOSBandi for MultiWii 2.3 (2013).
+
+The format is defined the XSD schema here.
+
+* Lower case tags are preferred by inav. Older tools may prefer uppercase (the original MW usage).
+* For inav 4.0 and later, the `missionitem/flags` attribute is required for "fly-by home" waypoints and multi-mission files.
+* For inav 4.0 and later, multi-mission files; mission segments are delimited by a flag value of `165` (the MSP protocol value).
+* For multi-mission files, the waypoints may be numbered either sequentially across the whole file, or "reset-numbering" within each mission segment. The latter may (or not) be considered to be more "human readable".
+* The `mwp` tag was introduced by the eponymous mission planner. Other mission planners may consider that reusing some of the tags (`cx`, `cy` - centre location, `zoom` TMS zoom level) is useful.
+* The `version` tag may be intepreted by mission planners as they see fit. For example, the (obsolete) Android 'ez-gui' application requires '2.3-pre8'. For multi-mission files it is recommended to use another `version`.
+
+## Examples
+
+### Multi-mission file with sequential numbering
+
+```
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+```
+
+### Multi-mission file with "reset" numbering and per-segment metadata
+
+```
+
+
+
+
+