diff --git a/libraries/RC_Channel/RC_Channel.cpp b/libraries/RC_Channel/RC_Channel.cpp
index 48b09632cf..76458ba691 100644
--- a/libraries/RC_Channel/RC_Channel.cpp
+++ b/libraries/RC_Channel/RC_Channel.cpp
@@ -496,16 +496,24 @@ void RC_Channel::output_trim_all()
     }
 }
 
+/*
+  setup the failsafe value to the trim value for all channels in chmask
+ */
+void RC_Channel::setup_failsafe_trim_mask(uint16_t chmask)
+{
+    for (uint8_t i=0; i<RC_MAX_CHANNELS; i++) {
+        if (_rc_ch[i] != NULL && ((1U<<i)&chmask)) {
+            hal.rcout->set_failsafe_pwm(1U<<i, _rc_ch[i]->_radio_trim);
+        }
+    }
+}
+
 /*
   setup the failsafe value to the trim value for all channels
  */
 void RC_Channel::setup_failsafe_trim_all()
 {
-    for (uint8_t i=0; i<RC_MAX_CHANNELS; i++) {
-        if (_rc_ch[i] != NULL) {
-            hal.rcout->set_failsafe_pwm(1U<<i, _rc_ch[i]->_radio_trim);
-        }
-    }
+    setup_failsafe_trim_mask(0xFFFF);
 }
 
 void
diff --git a/libraries/RC_Channel/RC_Channel.h b/libraries/RC_Channel/RC_Channel.h
index 75f59761bd..3da2fe5929 100644
--- a/libraries/RC_Channel/RC_Channel.h
+++ b/libraries/RC_Channel/RC_Channel.h
@@ -108,6 +108,7 @@ public:
     void        output() const;
     void        output_trim() const;
     static void output_trim_all();
+    static void setup_failsafe_trim_mask(uint16_t chmask);
     static void setup_failsafe_trim_all();
     uint16_t    read() const;
     void        input();