diff --git a/libraries/AP_Tuning/AP_Tuning.cpp b/libraries/AP_Tuning/AP_Tuning.cpp
index 5fe82a53af..05c4273b51 100644
--- a/libraries/AP_Tuning/AP_Tuning.cpp
+++ b/libraries/AP_Tuning/AP_Tuning.cpp
@@ -233,6 +233,13 @@ void AP_Tuning::check_input(uint8_t flightmode)
  */
 void AP_Tuning::Log_Write_Parameter_Tuning(float value)
 {
+// @LoggerMessage: PRTN
+// @Description: Plane Parameter Tuning data
+// @Field: TimeUS: Time since system startup
+// @Field: Set: Parameter set being tuned
+// @Field: Parm: Parameter being tuned
+// @Field: Value: Current parameter value
+// @Field: CenterValue: Center value (startpoint of current modifications) of parameter being tuned
     AP::logger().Write("PRTN", "TimeUS,Set,Parm,Value,CenterValue", "QBBff",
                                            AP_HAL::micros64(),
                                            parmset,