diff --git a/libraries/DataFlash/DataFlash.h b/libraries/DataFlash/DataFlash.h
index 05f95ef512..d3438dc896 100644
--- a/libraries/DataFlash/DataFlash.h
+++ b/libraries/DataFlash/DataFlash.h
@@ -99,6 +99,7 @@ public:
         float I;
         float D;
         float FF;
+        float AFF;
     };
 
     void Log_Write_PID(uint8_t msg_type, const PID_Info &info);
@@ -442,6 +443,7 @@ struct PACKED log_PID {
     float   I;
     float   D;
     float   FF;
+    float   AFF;
 };
 
 struct PACKED log_Current {
@@ -635,11 +637,11 @@ Format characters in the format string for binary log messages
     { LOG_MODE_MSG, sizeof(log_Mode), \
       "MODE", "QMB",         "TimeUS,Mode,ModeNum" }
     { LOG_PIDR_MSG, sizeof(log_PID), \
-      "PIDR", "Qffff",  "TimeUS,P,I,D,FF" }, \
+      "PIDR", "Qfffff",  "TimeUS,P,I,D,FF,AFF" }, \
     { LOG_PIDP_MSG, sizeof(log_PID), \
-      "PIDP", "Qffff",  "TimeUS,P,I,D,FF" }, \
+      "PIDP", "Qfffff",  "TimeUS,P,I,D,FF,AFF" }, \
     { LOG_PIDY_MSG, sizeof(log_PID), \
-      "PIDY", "Qffff",  "TimeUS,P,I,D,FF" }
+      "PIDY", "Qfffff",  "TimeUS,P,I,D,FF,AFF" }
 
 // messages for more advanced boards
 #define LOG_EXTRA_STRUCTURES \
diff --git a/libraries/DataFlash/LogFile.cpp b/libraries/DataFlash/LogFile.cpp
index dd98e178dd..44ff7d6a41 100644
--- a/libraries/DataFlash/LogFile.cpp
+++ b/libraries/DataFlash/LogFile.cpp
@@ -1337,7 +1337,8 @@ void DataFlash_Class::Log_Write_PID(uint8_t msg_type, const PID_Info &info)
         P               : info.P,
         I               : info.I,
         D               : info.D,
-        FF              : info.FF
+        FF              : info.FF,
+        AFF             : info.AFF
     };
     WriteBlock(&pkt, sizeof(pkt));
 }