Work around quirkiness with ArduPilot and LOITER_* NaN handling on heading.

src/FirmwarePlugin/APM/MavCmdInfoCommon.json

@@ -10,6 +10,36 @@
             "paramRemove":  "2"
         },
         {
+            "id":                   17,
+            "comment":              "MAV_CMD_NAV_LOITER_UNLIM",
+            "param4": {
+                "label":            "Heading",
+                "units":            "radians",
+                "default":          0,
+                "decimalPlaces":    2
+            }
+        },
+        {
+            "id":                   18,
+            "comment":              "MAV_CMD_NAV_LOITER_TURNS",
+            "param4": {
+                "label":            "Heading",
+                "units":            "radians",
+                "default":          0,
+                "decimalPlaces":    2
+            }
+        },
+        {
+            "id":                   19,
+            "comment":              "MAV_CMD_NAV_LOITER_TIME",
+            "param4": {
+                "label":            "Heading",
+                "units":            "radians",
+                "default":          0,
+                "decimalPlaces":    2
+            }
+        },
+        {
             "id":                       22,
             "comment":                  "MAV_CMD_NAV_TAKEOFF",
             "specifiesCoordinate":      false,

src/FirmwarePlugin/APM/MavCmdInfoFixedWing.json

@@ -10,6 +10,28 @@
             "paramRemove":  "1,3,4"
         },
         {
+            "id":           18,
+            "comment":      "MAV_CMD_NAV_LOITER_TURNS",
+            "param4": {
+                "label":            "Exit loiter from",
+                "enumStrings":      "Center,Tangent",
+                "enumValues":       "0,1",
+                "default":          1,
+                "decimalPlaces":    0
+            }
+        },
+        {
+            "id":           19,
+            "comment":      "MAV_CMD_NAV_LOITER_TIME",
+            "param4": {
+                "label":            "Exit loiter from",
+                "enumStrings":      "Center,Tangent",
+                "enumValues":       "0,1",
+                "default":          1,
+                "decimalPlaces":    0
+            }
+        },
+        {
             "id":           21,
             "comment":      "MAV_CMD_NAV_LAND",
             "paramRemove":  "4"

src/FirmwarePlugin/PX4/MavCmdInfoCommon.json

@@ -10,39 +10,6 @@
             "paramRemove":  "2,3"
         },
         {
-            "id":                   17,
-            "comment":              "MAV_CMD_NAV_LOITER_UNLIM",
-            "param4": {
-                "label":            "Heading",
-                "units":            "radians",
-                "nanUnchanged":     true,
-                "default":          null,
-                "decimalPlaces":    2
-            }
-        },
-        {
-            "id":                   18,
-            "comment":              "MAV_CMD_NAV_LOITER_TURNS",
-            "param4": {
-                "label":            "Heading",
-                "units":            "radians",
-                "nanUnchanged":     true,
-                "default":          null,
-                "decimalPlaces":    2
-            }
-        },
-        {
-            "id":                   19,
-            "comment":              "MAV_CMD_NAV_LOITER_TIME",
-            "param4": {
-                "label":            "Heading",
-                "units":            "radians",
-                "nanUnchanged":     true,
-                "default":          null,
-                "decimalPlaces":    2
-            }
-        },
-        {
             "id":           21,
             "comment":      "MAV_CMD_NAV_LAND",
             "paramRemove":  "1"

src/MissionManager/MavCmdInfoCommon.json

@@ -101,7 +101,8 @@
             "param4": {
                 "label":            "Heading",
                 "units":            "radians",
-                "default":          0,
+                "nanUnchanged":     true,
+                "default":          null,
                 "decimalPlaces":    2
             }
         },
@@ -128,7 +129,8 @@
             "param4": {
                 "label":            "Heading",
                 "units":            "radians",
-                "default":          0,
+                "nanUnchanged":     true,
+                "default":          null,
                 "decimalPlaces":    2
             }
         },