diff --git a/src/modules/navigator/navigation.h b/src/modules/navigator/navigation.h
index 5c6251d603..132c3923c3 100644
--- a/src/modules/navigator/navigation.h
+++ b/src/modules/navigator/navigation.h
@@ -49,7 +49,7 @@
 #elif defined(__PX4_POSIX)
 #  define NUM_MISSIONS_SUPPORTED (UINT16_MAX-1) // This is allocated as needed.
 #else
-#  define NUM_MISSIONS_SUPPORTED 2000 // This allocates a file of around 181 kB on the SD card.
+#  define NUM_MISSIONS_SUPPORTED 500
 #endif
 
 #define NAV_EPSILON_POSITION	0.001f	/**< Anything smaller than this is considered zero */