diff --git a/libraries/AP_Terrain/AP_Terrain.cpp b/libraries/AP_Terrain/AP_Terrain.cpp
index 3f5ba26c31..e925662e16 100644
--- a/libraries/AP_Terrain/AP_Terrain.cpp
+++ b/libraries/AP_Terrain/AP_Terrain.cpp
@@ -56,9 +56,8 @@ const AP_Param::GroupInfo AP_Terrain::var_info[] = {
 };
 
 // constructor
-AP_Terrain::AP_Terrain(const AP_Mission &_mission, const AP_Rally &_rally) :
+AP_Terrain::AP_Terrain(const AP_Mission &_mission) :
     mission(_mission),
-    rally(_rally),
     disk_io_state(DiskIoIdle),
     fd(-1)
 {
diff --git a/libraries/AP_Terrain/AP_Terrain.h b/libraries/AP_Terrain/AP_Terrain.h
index bcaad7dcdb..c090690aab 100644
--- a/libraries/AP_Terrain/AP_Terrain.h
+++ b/libraries/AP_Terrain/AP_Terrain.h
@@ -29,7 +29,6 @@
 #include <AP_Param/AP_Param.h>
 #include <AP_AHRS/AP_AHRS.h>
 #include <AP_Mission/AP_Mission.h>
-#include <AP_Rally/AP_Rally.h>
 
 #define TERRAIN_DEBUG 0
 
@@ -76,7 +75,7 @@
 
 class AP_Terrain {
 public:
-    AP_Terrain(const AP_Mission &_mission, const AP_Rally &_rally);
+    AP_Terrain(const AP_Mission &_mission);
 
     /* Do not allow copies */
     AP_Terrain(const AP_Terrain &other) = delete;
@@ -340,10 +339,6 @@ private:
     // all waypoints
     const AP_Mission &mission;
 
-    // reference to AP_Rally, so we can ask preload terrain data for 
-    // all rally points
-    const AP_Rally &rally;
-
     // cache of grids in memory, LRU
     uint8_t cache_size = 0;
     struct grid_cache *cache = nullptr;
diff --git a/libraries/AP_Terrain/TerrainMission.cpp b/libraries/AP_Terrain/TerrainMission.cpp
index 02846ac99a..ffb2b2aa98 100644
--- a/libraries/AP_Terrain/TerrainMission.cpp
+++ b/libraries/AP_Terrain/TerrainMission.cpp
@@ -19,6 +19,7 @@
 #include <AP_HAL/AP_HAL.h>
 #include <AP_Common/AP_Common.h>
 #include <AP_Math/AP_Math.h>
+#include <AP_Rally/AP_Rally.h>
 #include <GCS_MAVLink/GCS_MAVLink.h>
 #include <GCS_MAVLink/GCS.h>
 #include "AP_Terrain.h"
@@ -110,11 +111,16 @@ void AP_Terrain::update_mission_data(void)
  */
 void AP_Terrain::update_rally_data(void)
 {
-    if (last_rally_change_ms != rally.last_change_time_ms() ||
+    const AP_Rally *rally = AP::rally();
+    if (rally == nullptr) {
+        return;
+    }
+
+    if (last_rally_change_ms != rally->last_change_time_ms() ||
         last_rally_spacing != grid_spacing) {
         // a rally point has changed - start again
         next_rally_index = 1;
-        last_rally_change_ms = rally.last_change_time_ms();
+        last_rally_change_ms = rally->last_change_time_ms();
         last_rally_spacing = grid_spacing;
     }
     if (next_rally_index == 0) {
@@ -132,7 +138,7 @@ void AP_Terrain::update_rally_data(void)
     while (true) {
         // get next rally point
         struct RallyLocation rp;
-        if (!rally.get_rally_point_with_index(next_rally_index, rp)) {
+        if (!rally->get_rally_point_with_index(next_rally_index, rp)) {
             // nothing more to do
             next_rally_index = 0;
             return;