diff --git a/ArduCopter/AP_Arming.cpp b/ArduCopter/AP_Arming.cpp
index 60b97706af..0346ccf295 100644
--- a/ArduCopter/AP_Arming.cpp
+++ b/ArduCopter/AP_Arming.cpp
@@ -169,7 +169,7 @@ bool AP_Arming_Copter::parameter_checks(bool display_failure)
         }
 
         char fail_msg[50];
-        // check input mangager parameters
+        // check input manager parameters
         if (!copter.input_manager.parameter_check(fail_msg, ARRAY_SIZE(fail_msg))) {
             check_failed(ARMING_CHECK_PARAMETERS, display_failure, "%s", fail_msg);
             return false;
diff --git a/ArduCopter/crash_check.cpp b/ArduCopter/crash_check.cpp
index 253d359a05..b57114ae7c 100644
--- a/ArduCopter/crash_check.cpp
+++ b/ArduCopter/crash_check.cpp
@@ -191,7 +191,7 @@ void Copter::yaw_imbalance_check()
         return;
     }
 
-    // thrust loss is trigerred, yaw issues are expected
+    // thrust loss is triggered, yaw issues are expected
     if (motors->get_thrust_boost()) {
         yaw_I_filt.reset(0.0f);
         return;
@@ -219,8 +219,8 @@ void Copter::yaw_imbalance_check()
 
     const float I_max = attitude_control->get_rate_yaw_pid().imax();
     if ((is_positive(I_max) && ((I > YAW_IMBALANCE_IMAX_THRESHOLD * I_max) || (is_equal(I_term,I_max))))) {
-        // filtered using over precentage of I max or unfiltered = I max
-        // I makes up more than precentage of total available control power
+        // filtered using over percentage of I max or unfiltered = I max
+        // I makes up more than percentage of total available control power
         const uint32_t now = millis();
         if (now - last_yaw_warn_ms > YAW_IMBALANCE_WARN_MS) {
             last_yaw_warn_ms = now;
diff --git a/ArduCopter/mode.cpp b/ArduCopter/mode.cpp
index c20194d734..ba1f506e2c 100644
--- a/ArduCopter/mode.cpp
+++ b/ArduCopter/mode.cpp
@@ -772,7 +772,7 @@ void Mode::precland_retry_position(const Vector3f &retry_pos)
         }
 
         // allow user to take control during repositioning. Note: copied from land_run_horizontal_control()
-        // To-Do: this code exists at several different places in slightly diffrent forms and that should be fixed
+        // To-Do: this code exists at several different places in slightly different forms and that should be fixed
         if (g.land_repositioning) {
             float target_roll = 0.0f;
             float target_pitch = 0.0f;
@@ -796,7 +796,7 @@ void Mode::precland_retry_position(const Vector3f &retry_pos)
     }
 
     Vector3p retry_pos_NEU{retry_pos.x, retry_pos.y, retry_pos.z * -1.0f};
-    //pos contoller expects input in NEU cm's
+    // pos controller expects input in NEU cm's
     retry_pos_NEU = retry_pos_NEU * 100.0f;
     pos_control->input_pos_xyz(retry_pos_NEU, 0.0f, 1000.0f);
 
diff --git a/ArduCopter/mode.h b/ArduCopter/mode.h
index 522816a3a3..890446daa9 100644
--- a/ArduCopter/mode.h
+++ b/ArduCopter/mode.h
@@ -633,7 +633,7 @@ private:
         int8_t pitch_deg;   // target pitch angle in degrees.  provided by mission command
         int16_t yaw_deg;    // target yaw angle in degrees.  provided by mission command
         float climb_rate;   // climb rate in m/s. provided by mission command
-        uint32_t start_ms;  // system time that nav attitude time command was recieved (used for timeout)
+        uint32_t start_ms;  // system time that nav attitude time command was received (used for timeout)
     } nav_attitude_time;
 };
 
diff --git a/ArduCopter/mode_autorotate.cpp b/ArduCopter/mode_autorotate.cpp
index dc8873c14c..fb009a1d34 100644
--- a/ArduCopter/mode_autorotate.cpp
+++ b/ArduCopter/mode_autorotate.cpp
@@ -41,7 +41,7 @@ bool ModeAutorotate::init(bool ignore_checks)
     g2.arot.init_hs_controller();
     g2.arot.init_fwd_spd_controller();
 
-    // Retrive rpm and start rpm sensor health checks
+    // Retrieve rpm and start rpm sensor health checks
     _initial_rpm = g2.arot.get_rpm(true);
 
     // Display message 
@@ -173,7 +173,7 @@ void ModeAutorotate::run()
                 g2.arot.set_desired_fwd_speed();
 
                 // Set target head speed in head speed controller
-                _target_head_speed = HEAD_SPEED_TARGET_RATIO;  //Ensure target hs is set to glide incase hs hasent reached target for glide
+                _target_head_speed = HEAD_SPEED_TARGET_RATIO;  //Ensure target hs is set to glide in case hs hasent reached target for glide
                 g2.arot.set_target_head_speed(_target_head_speed);
 
                 // Prevent running the initial glide functions again
@@ -209,7 +209,7 @@ void ModeAutorotate::run()
                     gcs().send_text(MAV_SEVERITY_INFO, "Bailing Out of Autorotation");
                 #endif
 
-                // Set bail out timer remaining equal to the paramter value, bailout time 
+                // Set bail out timer remaining equal to the parameter value, bailout time 
                 // cannot be less than the motor spool-up time: BAILOUT_MOTOR_RAMP_TIME.
                 _bail_time = MAX(g2.arot.get_bail_time(),BAILOUT_MOTOR_RAMP_TIME+0.1f);
 
diff --git a/ArduCopter/system.cpp b/ArduCopter/system.cpp
index 6ff9bb1f6e..1c5fc5f7dd 100644
--- a/ArduCopter/system.cpp
+++ b/ArduCopter/system.cpp
@@ -77,7 +77,7 @@ void Copter::init_ardupilot()
     init_rc_in();               // sets up rc channels from radio
 
     // initialise surface to be tracked in SurfaceTracking
-    // must be before rc init to not override inital switch position
+    // must be before rc init to not override initial switch position
     surface_tracking.init((SurfaceTracking::Surface)copter.g2.surftrak_mode.get());
 
     // allocate the motors class