diff --git a/libraries/AP_HAL/RCOutput.h b/libraries/AP_HAL/RCOutput.h
index 02787780af..145d654460 100644
--- a/libraries/AP_HAL/RCOutput.h
+++ b/libraries/AP_HAL/RCOutput.h
@@ -17,6 +17,7 @@
 #define CH_9 8
 #define CH_10 9
 #define CH_11 10
+#define CH_12 11
 #endif