diff --git a/libraries/AP_WindVane/AP_WindVane.cpp b/libraries/AP_WindVane/AP_WindVane.cpp
index 14b51ac438..f85975581b 100644
--- a/libraries/AP_WindVane/AP_WindVane.cpp
+++ b/libraries/AP_WindVane/AP_WindVane.cpp
@@ -13,21 +13,16 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <AP_WindVane/AP_WindVane.h>
-#include <AP_BoardConfig/AP_BoardConfig.h>
-#include <RC_Channel/RC_Channel.h>
-#include <AP_AHRS/AP_AHRS.h>
-#include <GCS_MAVLink/GCS.h>
-#include <Filter/Filter.h>
-#include <utility>
-#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
-#include <SITL/SITL.h>
-#endif
+#include "AP_WindVane.h"
 
-extern const AP_HAL::HAL& hal;
+#include "AP_WindVane_Home.h"
+#include "AP_WindVane_Analog.h"
+#include "AP_WindVane_ModernDevice.h"
+#include "AP_WindVane_Airspeed.h"
+#include "AP_WindVane_RPM.h"
+#include "AP_WindVane_SITL.h"
 
 #define WINDVANE_DEFAULT_PIN 15                     // default wind vane sensor analog pin
-#define WINDVANE_CALIBRATION_VOLT_DIFF_MIN  1.0f    // calibration routine's min voltage difference required for success
 #define WINDSPEED_DEFAULT_SPEED_PIN 14              // default pin for reading speed from ModernDevice rev p wind sensor
 #define WINDSPEED_DEFAULT_TEMP_PIN 13               // default pin for reading temperature from ModernDevice rev p wind sensor
 #define WINDSPEED_DEFAULT_VOLT_OFFSET 1.346         // default voltage offset between speed and temp pins from ModernDevice rev p wind sensor
@@ -39,7 +34,8 @@ const AP_Param::GroupInfo AP_WindVane::var_info[] = {
     // @Description: Wind Vane type
     // @Values: 0:None,1:Heading when armed,2:RC input offset heading when armed,3:Analog
     // @User: Standard
-    AP_GROUPINFO_FLAGS("TYPE", 1, AP_WindVane, _type, 0, AP_PARAM_FLAG_ENABLE),
+    // @RebootRequired: True
+    AP_GROUPINFO_FLAGS("TYPE", 1, AP_WindVane, _direction_type, 0, AP_PARAM_FLAG_ENABLE),
 
     // @Param: RC_IN_NO
     // @DisplayName: Wind vane sensor RC Input Channel
@@ -92,8 +88,8 @@ const AP_Param::GroupInfo AP_WindVane::var_info[] = {
 
     // @Param: CAL
     // @DisplayName: Wind vane calibration start
-    // @Description: Start wind vane calibration by setting this to 1
-    // @Values: 0:None, 1:Calibrate
+    // @Description: Start wind vane calibration by setting this to 1 or 2
+    // @Values: 0:None, 1:Calibrate direction, 2:Calibrate speed
     // @User: Standard
     AP_GROUPINFO("CAL", 8, AP_WindVane, _calibration, 0),
 
@@ -120,6 +116,7 @@ const AP_Param::GroupInfo AP_WindVane::var_info[] = {
     // @Description: Wind speed sensor type
     // @Values: 0:None,1:Airspeed library,2:Modern Devices Wind Sensor,3:RPM library,10:SITL
     // @User: Standard
+    // @RebootRequired: True
     AP_GROUPINFO("SPEED_TYPE", 11, AP_WindVane, _speed_sensor_type,  0),
 
     // @Param: SPEED_PIN
@@ -178,60 +175,113 @@ AP_WindVane *AP_WindVane::get_singleton()
 // return true if wind vane is enabled
 bool AP_WindVane::enabled() const
 {
-    return (_type != WINDVANE_NONE);
+    return _direction_type != WINDVANE_NONE;
 }
 
 // Initialize the Wind Vane object and prepare it for use
 void AP_WindVane::init()
 {
-    // a pin for reading the Wind Vane voltage
-    dir_analog_source = hal.analogin->channel(_dir_analog_pin);
+    // don't init twice
+    if (_direction_driver != nullptr || _speed_driver != nullptr ) {
+        return;
+    }
 
-    // pins for ModernDevice rev p wind sensor
-    speed_analog_source = hal.analogin->channel(ANALOG_INPUT_NONE);
-    speed_temp_analog_source = hal.analogin->channel(ANALOG_INPUT_NONE);
+    // wind direction
+    switch (_direction_type) {
+        case WindVaneType::WINDVANE_NONE:
+            // WindVane disabled
+            return;
+        case WindVaneType::WINDVANE_HOME_HEADING:
+        case WindVaneType::WINDVANE_PWM_PIN:
+            _direction_driver = new AP_WindVane_Home(*this);
+            break;
+        case WindVaneType::WINDVANE_ANALOG_PIN:
+            _direction_driver = new AP_WindVane_Analog(*this);
+            break;
+        case WindVaneType::WINDVANE_SITL:
+#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
+            _direction_driver = new AP_WindVane_SITL(*this);
+#endif
+            break;
+    }
 
-    // check that airspeed is enabled if it is selected as sensor type, if not revert to no wind speed sensor
-    AP_Airspeed* airspeed = AP_Airspeed::get_singleton();
-    if (_speed_sensor_type == Speed_type::WINDSPEED_AIRSPEED && (airspeed == nullptr || !airspeed->enabled())) {
-        _speed_sensor_type.set(Speed_type::WINDSPEED_NONE);
+    // wind speed
+    switch (_speed_sensor_type) {
+        case Speed_type::WINDSPEED_NONE:
+            break;
+        case Speed_type::WINDSPEED_AIRSPEED:
+            _speed_driver = new AP_WindVane_Airspeed(*this);
+            break;
+        case Speed_type::WINDVANE_WIND_SENSOR_REV_P:
+            _speed_driver = new AP_WindVane_ModernDevice(*this);
+            break;
+        case Speed_type::WINDSPEED_SITL:
+#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
+            // single driver does both speed and direction
+            if (_direction_type != WINDVANE_SITL) {
+                _speed_driver = new AP_WindVane_SITL(*this);
+            } else {
+                _speed_driver = _direction_driver;
+            }
+#endif
+            break;
+        case Speed_type::WINDSPEED_RPM:
+            _speed_driver = new AP_WindVane_RPM(*this);
+            break;
     }
 }
 
 // update wind vane, expected to be called at 20hz
 void AP_WindVane::update()
 {
+    bool have_speed = _speed_driver != nullptr;
+    bool have_direciton = _direction_driver != nullptr;
+
     // exit immediately if not enabled
-    if (!enabled()) {
+    if (!enabled() || (!have_speed && !have_direciton)) {
         return;
     }
 
-    // check for calibration
-    calibrate();
+    // calibrate if booted and disarmed
+    if (!hal.util->get_soft_armed()) {
+        if (_calibration == 1 && have_direciton) {
+            _direction_driver->calibrate();
+        } else if (_calibration == 2 && have_speed) {
+            _speed_driver->calibrate();
+        } else if (_calibration != 0) {
+            gcs().send_text(MAV_SEVERITY_INFO, "WindVane: driver not found");
+            _calibration.set_and_save(0);
+        }
+    } else if (_calibration != 0) {
+        gcs().send_text(MAV_SEVERITY_INFO, "WindVane: disarm for cal");
+        _calibration.set_and_save(0);
+    }
 
     // read apparent wind speed
-    update_apparent_wind_speed();
+    if (have_speed) {
+        _speed_driver->update_speed();
+    }
 
-    // read apparent wind direction (relies on wind speed above)
-    update_apparent_wind_direction();
+    // read apparent wind direction
+    if (_speed_apparent >= _dir_speed_cutoff && have_direciton) {
+        // only update if enough wind to move vane
+        _direction_driver->update_direction();
+    }
 
     // calculate true wind speed and direction from apparent wind
-    update_true_wind_speed_and_direction();
+    if (have_speed && have_direciton) {
+        update_true_wind_speed_and_direction();
+    } else {
+        // no wind speed sensor, so can't do true wind calcs
+        _direction_absolute = _direction_apparent_ef;
+        _speed_true = 0.0f;
+        return;
+    }
 }
 
-// get the apparent wind direction in radians, 0 = head to wind
-float AP_WindVane::get_apparent_wind_direction_rad() const
-{
-    return wrap_PI(_direction_apparent_ef - AP::ahrs().yaw);
-}
 
-// record home heading for use as wind direction if no sensor is fitted
-void AP_WindVane::record_home_heading()
-{
-    _home_heading = AP::ahrs().yaw;
-}
-
-bool AP_WindVane::start_calibration()
+// to start direction calibration from mavlink or other
+bool AP_WindVane::start_direction_calibration()
 {
     if (enabled() && (_calibration == 0)) {
         _calibration = 1;
@@ -240,6 +290,16 @@ bool AP_WindVane::start_calibration()
     return false;
 }
 
+// to start speed calibration from mavlink or other
+bool AP_WindVane::start_speed_calibration()
+{
+    if (enabled() && (_calibration == 0)) {
+        _calibration = 2;
+        return true;
+    }
+    return false;
+}
+
 // send mavlink wind message
 void AP_WindVane::send_wind(mavlink_channel_t chan)
 {
@@ -256,204 +316,10 @@ void AP_WindVane::send_wind(mavlink_channel_t chan)
         0);
 }
 
-// read an analog port and calculate the wind direction in earth-frame in radians
-// assumes voltage increases as wind vane moves clockwise
-float AP_WindVane::read_analog_direction_ef()
-{
-    dir_analog_source->set_pin(_dir_analog_pin);
-    _current_analog_voltage = dir_analog_source->voltage_average_ratiometric();
-
-    const float voltage_ratio = linear_interpolate(0.0f, 1.0f, _current_analog_voltage, _dir_analog_volt_min, _dir_analog_volt_max);
-    const float direction = (voltage_ratio * radians(360 - _dir_analog_deadzone)) + radians(_dir_analog_bearing_offset);
-
-    return wrap_PI(direction + AP::ahrs().yaw);
-}
-
-// read rc input of apparent wind direction in earth-frame in radians
-float AP_WindVane::read_PWM_direction_ef()
-{
-    RC_Channel *chan = rc().channel(_rc_in_no-1);
-    if (chan == nullptr) {
-        return 0.0f;
-    }
-    float direction = chan->norm_input() * radians(45);
-
-    return wrap_PI(direction + _home_heading);
-}
-
-#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
-// read SITL's apparent wind direction in earth-frame in radians
-float AP_WindVane::read_SITL_direction_ef()
-{
-    // temporarily store true speed and direction for easy access
-    const float wind_speed = AP::sitl()->wind_speed_active;
-    const float wind_dir_rad = radians(AP::sitl()->wind_direction_active);
-
-    // Note than the SITL wind direction is defined as the direction the wind is traveling to
-    // This is accounted for in these calculations
-
-    // convert true wind speed and direction into a 2D vector
-    Vector2f wind_vector_ef(cosf(wind_dir_rad) * wind_speed, sinf(wind_dir_rad) * wind_speed);
-
-    // add vehicle speed to get apparent wind vector
-    wind_vector_ef.x += AP::sitl()->state.speedN;
-    wind_vector_ef.y += AP::sitl()->state.speedE;
-
-    return atan2f(wind_vector_ef.y, wind_vector_ef.x);
-}
-
-// read the apparent wind speed in m/s from SITL
-float AP_WindVane::read_wind_speed_SITL()
-{
-    // temporarily store true speed and direction for easy access
-    const float wind_speed = AP::sitl()->wind_speed_active;
-    const float wind_dir_rad = radians(AP::sitl()->wind_direction_active);
-
-    // convert true wind speed and direction into a 2D vector
-    Vector2f wind_vector_ef(cosf(wind_dir_rad) * wind_speed, sinf(wind_dir_rad) * wind_speed);
-
-    // add vehicle speed to get apparent wind vector
-    wind_vector_ef.x += AP::sitl()->state.speedN;
-    wind_vector_ef.y += AP::sitl()->state.speedE;
-
-    return wind_vector_ef.length();
-}
-#endif
-
-// read wind speed from Modern Device rev p wind sensor
-// https://moderndevice.com/news/calibrating-rev-p-wind-sensor-new-regression/
-float AP_WindVane::read_wind_speed_ModernDevice()
-{
-    float analog_voltage = 0.0f;
-
-    // only read temp pin if defined, sensor will do OK assuming constant temp
-    float temp_ambient = 28.0f; // equations were generated at this temp in above data sheet
-    if (is_positive(_speed_sensor_temp_pin)) {
-        speed_temp_analog_source->set_pin(_speed_sensor_temp_pin);
-        analog_voltage = speed_temp_analog_source->voltage_average();
-        temp_ambient = (analog_voltage - 0.4f) / 0.0195f; // deg C
-        // constrain to reasonable range to avoid deviating from calibration too much and potential divide by zero
-        temp_ambient = constrain_float(temp_ambient, 10.0f, 40.0f);
-    }
-
-    speed_analog_source->set_pin(_speed_sensor_speed_pin);
-    analog_voltage = speed_analog_source->voltage_average();
-
-    // apply voltage offset and make sure not negative
-    // by default the voltage offset is the number provide by the manufacturer
-    analog_voltage = analog_voltage - _speed_sensor_voltage_offset;
-    if (is_negative(analog_voltage)) {
-        analog_voltage = 0.0f;
-    }
-
-    // simplified equation from data sheet, converted from mph to m/s
-    return 24.254896f * powf((analog_voltage / powf(temp_ambient, 0.115157f)), 3.009364f);
-}
-
-// update the apparent wind speed
-void AP_WindVane::update_apparent_wind_speed()
-{
-    float apparent_speed_in = 0.0f;
-
-    switch (_speed_sensor_type) {
-        case WINDSPEED_NONE:
-            _speed_apparent = 0.0f;
-            break;
-        case WINDSPEED_AIRSPEED: {
-            const AP_Airspeed* airspeed = AP_Airspeed::get_singleton();
-            if (airspeed != nullptr) {
-                apparent_speed_in = airspeed->get_airspeed();
-            }
-            break;
-        }
-        case WINDVANE_WIND_SENSOR_REV_P:
-            apparent_speed_in = read_wind_speed_ModernDevice();
-            break;
-        case WINDSPEED_SITL:
-#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
-            apparent_speed_in = read_wind_speed_SITL();
-#endif
-            break;
-        case WINDSPEED_RPM: {
-            const AP_RPM* rpm = AP_RPM::get_singleton();
-            if (rpm != nullptr) {
-                const float temp_speed = rpm->get_rpm(0);
-                if (!is_negative(temp_speed)) {
-                    apparent_speed_in = temp_speed;
-                }
-            }
-            break;
-        }
-    }
-
-    // apply low pass filter if enabled
-    if (is_positive(_speed_filt_hz)) {
-        _speed_filt.set_cutoff_frequency(_speed_filt_hz);
-        _speed_apparent = _speed_filt.apply(apparent_speed_in, 0.02f);
-    } else {
-        _speed_apparent = apparent_speed_in;
-    }
-}
-
-// calculate the apparent wind direction in radians, the wind comes from this direction, 0 = head to wind
-// expected to be called at 20hz after apparent wind speed has been updated
-void AP_WindVane::update_apparent_wind_direction()
-{
-    float apparent_angle_ef = 0.0f;
-
-    switch (_type) {
-        case WindVaneType::WINDVANE_HOME_HEADING:
-            // this is a approximation as we are not considering boat speed and wind speed
-            // do not filter home heading
-            _direction_apparent_ef = _home_heading;
-            return;
-        case WindVaneType::WINDVANE_PWM_PIN:
-            // this is a approximation as we are not considering boat speed and wind speed
-            // do not filter pwm input from pilot
-            _direction_apparent_ef = read_PWM_direction_ef();
-            return;
-        case WindVaneType::WINDVANE_ANALOG_PIN:
-            apparent_angle_ef = read_analog_direction_ef();
-            break;
-        case WindVaneType::WINDVANE_SITL:
-#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
-            apparent_angle_ef = read_SITL_direction_ef();
-#endif
-            break;
-    }
-
-    // if not enough wind to move vane do not update the value
-    if (_speed_apparent < _dir_speed_cutoff){
-        return;
-    }
-
-    // apply low pass filter if enabled
-    if (is_positive(_dir_filt_hz)) {
-        _dir_sin_filt.set_cutoff_frequency(_dir_filt_hz);
-        _dir_cos_filt.set_cutoff_frequency(_dir_filt_hz);
-        // https://en.wikipedia.org/wiki/Mean_of_circular_quantities
-        const float filtered_sin = _dir_sin_filt.apply(sinf(apparent_angle_ef), 0.05f);
-        const float filtered_cos = _dir_cos_filt.apply(cosf(apparent_angle_ef), 0.05f);
-        _direction_apparent_ef = atan2f(filtered_sin, filtered_cos);
-    } else {
-        _direction_apparent_ef = apparent_angle_ef;
-    }
-
-    // make sure between -pi and pi
-    _direction_apparent_ef = wrap_PI(_direction_apparent_ef);
-}
-
 // calculate true wind speed and direction from apparent wind
 // https://en.wikipedia.org/wiki/Apparent_wind
 void AP_WindVane::update_true_wind_speed_and_direction()
 {
-    if (_speed_sensor_type == Speed_type::WINDSPEED_NONE) {
-        // no wind speed sensor, so can't do true wind calcs
-        _direction_absolute = _direction_apparent_ef;
-        _speed_true = 0.0f;
-        return;
-    }
-
     // if no vehicle speed, can't do calcs
     Vector3f veh_velocity;
     if (!AP::ahrs().get_velocity_NED(veh_velocity)) {
@@ -475,61 +341,6 @@ void AP_WindVane::update_true_wind_speed_and_direction()
     _speed_true = wind_true_vec.length();
 }
 
-// calibrate windvane
-void AP_WindVane::calibrate()
-{
-    // exit immediately if armed or too soon after start
-    if (hal.util->get_soft_armed()) {
-        return;
-    }
-
-    // return if not calibrating
-    if (_calibration == 0) {
-        return;
-    }
-
-    switch (_type) {
-        case WindVaneType::WINDVANE_HOME_HEADING:
-        case WindVaneType::WINDVANE_PWM_PIN:
-            gcs().send_text(MAV_SEVERITY_INFO, "WindVane: No cal required");
-            _calibration.set_and_save(0);
-            break;
-        case WindVaneType::WINDVANE_ANALOG_PIN:
-            // start calibration
-            if (_cal_start_ms == 0) {
-                _cal_start_ms = AP_HAL::millis();
-                _cal_volt_max = _current_analog_voltage;
-                _cal_volt_min = _current_analog_voltage;
-                gcs().send_text(MAV_SEVERITY_INFO, "WindVane: Calibration started, rotate wind vane");
-            }
-
-            // record min and max voltage
-            _cal_volt_max = MAX(_cal_volt_max, _current_analog_voltage);
-            _cal_volt_min = MIN(_cal_volt_min, _current_analog_voltage);
-
-            // calibrate for 30 seconds
-            if ((AP_HAL::millis() - _cal_start_ms) > 30000) {
-                // check for required voltage difference
-                const float volt_diff = _cal_volt_max - _cal_volt_min;
-                if (volt_diff >= WINDVANE_CALIBRATION_VOLT_DIFF_MIN) {
-                    // save min and max voltage
-                    _dir_analog_volt_max.set_and_save(_cal_volt_max);
-                    _dir_analog_volt_min.set_and_save(_cal_volt_min);
-                    _calibration.set_and_save(0);
-                    gcs().send_text(MAV_SEVERITY_INFO, "WindVane: Calibration complete (volt min:%.1f max:%1.f)",
-                            (double)_cal_volt_min,
-                            (double)_cal_volt_max);
-                } else {
-                    gcs().send_text(MAV_SEVERITY_INFO, "WindVane: Calibration failed (volt diff %.1f below %.1f)",
-                            (double)volt_diff,
-                            (double)WINDVANE_CALIBRATION_VOLT_DIFF_MIN);
-                }
-                _cal_start_ms = 0;
-            }
-            break;
-    }
-}
-
 AP_WindVane *AP_WindVane::_singleton = nullptr;
 
 namespace AP {
diff --git a/libraries/AP_WindVane/AP_WindVane.h b/libraries/AP_WindVane/AP_WindVane.h
index cbeb55595b..ec3e82fa8b 100644
--- a/libraries/AP_WindVane/AP_WindVane.h
+++ b/libraries/AP_WindVane/AP_WindVane.h
@@ -14,24 +14,22 @@
  */
 #pragma once
 
-#include <AP_HAL/AP_HAL.h>
 #include <AP_Param/AP_Param.h>
-#include <AP_Math/AP_Math.h>
-#include <AP_Airspeed/AP_Airspeed.h>
-#include <AP_RPM/AP_RPM.h>
+#include <AP_AHRS/AP_AHRS.h>
+
+class AP_WindVane_Backend;
 
 class AP_WindVane
 {
 
 public:
-
-    enum WindVaneType {
-        WINDVANE_NONE       = 0,
-        WINDVANE_HOME_HEADING = 1,
-        WINDVANE_PWM_PIN    = 2,
-        WINDVANE_ANALOG_PIN = 3,
-        WINDVANE_SITL       = 10
-    };
+    friend class AP_WindVane_Backend;
+    friend class AP_WindVane_Home;
+    friend class AP_WindVane_Analog;
+    friend class AP_WindVane_SITL;
+    friend class AP_WindVane_ModernDevice;
+    friend class AP_WindVane_Airspeed;
+    friend class AP_WindVane_RPM;
 
     AP_WindVane();
 
@@ -51,7 +49,9 @@ public:
     void update();
 
     // get the apparent wind direction in body-frame in radians, 0 = head to wind
-    float get_apparent_wind_direction_rad() const;
+    float get_apparent_wind_direction_rad() const {
+        return wrap_PI(_direction_apparent_ef - AP::ahrs().yaw);
+    }
 
     // get the absolute wind direction in radians, 0 = wind coming from north
     float get_absolute_wind_direction_rad() const { return _direction_absolute; }
@@ -62,11 +62,12 @@ public:
     // Return true wind speed
     float get_true_wind_speed() const { return _speed_true; }
 
-    // record home heading
-    void record_home_heading();
+    // record home heading for use as wind direction if no sensor is fitted
+    void record_home_heading() { _home_heading = AP::ahrs().yaw; }
 
     // start calibration routine
-    bool start_calibration();
+    bool start_direction_calibration();
+    bool start_speed_calibration();
 
     // send mavlink wind message
     void send_wind(mavlink_channel_t chan);
@@ -76,37 +77,8 @@ public:
 
 private:
 
-    // read an analog port and calculate the wind direction in earth-frame in radians
-    float read_analog_direction_ef();
-
-    // read rc input of apparent wind direction in earth-frame in radians
-    float read_PWM_direction_ef();
-
-#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
-    // read SITL's apparent wind direction in earth-frame in radians
-    float read_SITL_direction_ef();
-
-    // read the apparent wind speed in m/s from SITL
-    float read_wind_speed_SITL();
-#endif
-
-    // read wind speed from ModernDevice wind speed sensor rev p
-    float read_wind_speed_ModernDevice();
-
-    // update wind speed sensor
-    void update_apparent_wind_speed();
-
-    // update apparent wind direction
-    void update_apparent_wind_direction();
-
-    // calculate true wind speed and direction from apparent wind
-    void update_true_wind_speed_and_direction();
-
-    // calibrate
-    void calibrate();
-
     // parameters
-    AP_Int8 _type;                                  // type of windvane being used
+    AP_Int8 _direction_type;                        // type of windvane being used
     AP_Int8 _rc_in_no;                              // RC input channel to use
     AP_Int8 _dir_analog_pin;                        // analog pin connected to wind vane direction sensor
     AP_Float _dir_analog_volt_min;                  // minimum voltage read by windvane
@@ -122,22 +94,36 @@ private:
     AP_Float _speed_sensor_voltage_offset;          // analog speed zero wind voltage offset
     AP_Float _speed_filt_hz;                        // speed sensor low pass filter frequency
 
-    static AP_WindVane *_singleton;
+    AP_WindVane_Backend *_direction_driver;
+    AP_WindVane_Backend *_speed_driver;
+
+    // update wind speed sensor
+    void update_apparent_wind_speed();
+
+    // update apparent wind direction
+    void update_apparent_wind_direction();
+
+    // calculate true wind speed and direction from apparent wind
+    void update_true_wind_speed_and_direction();
 
     // wind direction variables
-    float _home_heading;                            // heading in radians recorded when vehicle was armed
     float _direction_apparent_ef;                   // wind's apparent direction in radians (0 = ahead of vehicle)
     float _direction_absolute;                      // wind's absolute direction in radians (0 = North)
-    float _current_analog_voltage;                  // wind direction's latest analog voltage reading
 
     // wind speed variables
     float _speed_apparent;                          // wind's apparent speed in m/s
     float _speed_true;                              // wind's true estimated speed in m/s
 
-    // calibration variables
-    uint32_t _cal_start_ms = 0;                     // calibration start time in milliseconds after boot
-    float _cal_volt_max;                            // maximum observed voltage during calibration
-    float _cal_volt_min;                            // minimum observed voltage during calibration
+    // heading in radians recorded when vehicle was armed
+    float _home_heading;
+
+    enum WindVaneType {
+        WINDVANE_NONE       = 0,
+        WINDVANE_HOME_HEADING = 1,
+        WINDVANE_PWM_PIN    = 2,
+        WINDVANE_ANALOG_PIN = 3,
+        WINDVANE_SITL       = 10
+    };
 
     enum Speed_type {
         WINDSPEED_NONE               = 0,
@@ -147,15 +133,7 @@ private:
         WINDSPEED_SITL               = 10
     };
 
-    // pin for reading analog voltage
-    AP_HAL::AnalogSource *dir_analog_source;
-    AP_HAL::AnalogSource *speed_analog_source;
-    AP_HAL::AnalogSource *speed_temp_analog_source;
-
-    // low pass filters of direction and speed
-    LowPassFilterFloat _dir_sin_filt = LowPassFilterFloat(2.0f);
-    LowPassFilterFloat _dir_cos_filt = LowPassFilterFloat(2.0f);
-    LowPassFilterFloat _speed_filt = LowPassFilterFloat(2.0f);
+    static AP_WindVane *_singleton;
 };
 
 namespace AP {
diff --git a/libraries/AP_WindVane/AP_WindVane_Airspeed.cpp b/libraries/AP_WindVane/AP_WindVane_Airspeed.cpp
new file mode 100644
index 0000000000..ee175900c0
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_Airspeed.cpp
@@ -0,0 +1,30 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "AP_WindVane_Airspeed.h"
+
+// constructor
+AP_WindVane_Airspeed::AP_WindVane_Airspeed(AP_WindVane &frontend) :
+    AP_WindVane_Backend(frontend)
+{
+}
+
+void AP_WindVane_Airspeed::update_speed()
+{
+    const AP_Airspeed* airspeed = AP_Airspeed::get_singleton();
+    if (airspeed != nullptr) {
+        speed_update_frontend(airspeed->get_airspeed());
+    }
+}
diff --git a/libraries/AP_WindVane/AP_WindVane_Airspeed.h b/libraries/AP_WindVane/AP_WindVane_Airspeed.h
new file mode 100644
index 0000000000..0f0bc748fe
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_Airspeed.h
@@ -0,0 +1,29 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include "AP_WindVane_Backend.h"
+
+#include <AP_Airspeed/AP_Airspeed.h>
+
+class AP_WindVane_Airspeed : public AP_WindVane_Backend
+{
+public:
+    // constructor
+    AP_WindVane_Airspeed(AP_WindVane &frontend);
+
+    // update state
+    void update_speed() override;
+};
diff --git a/libraries/AP_WindVane/AP_WindVane_Analog.cpp b/libraries/AP_WindVane/AP_WindVane_Analog.cpp
new file mode 100644
index 0000000000..36fc956108
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_Analog.cpp
@@ -0,0 +1,72 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "AP_WindVane_Analog.h"
+
+#define WINDVANE_CALIBRATION_VOLT_DIFF_MIN  1.0f    // calibration routine's min voltage difference required for success
+
+// constructor
+AP_WindVane_Analog::AP_WindVane_Analog(AP_WindVane &frontend) :
+    AP_WindVane_Backend(frontend)
+{
+    _dir_analog_source = hal.analogin->channel(ANALOG_INPUT_NONE);
+}
+
+void AP_WindVane_Analog::update_direction()
+{
+    _dir_analog_source->set_pin(_frontend._dir_analog_pin);
+    _current_analog_voltage = _dir_analog_source->voltage_average_ratiometric();
+
+    const float voltage_ratio = linear_interpolate(0.0f, 1.0f, _current_analog_voltage, _frontend._dir_analog_volt_min, _frontend._dir_analog_volt_max);
+    const float direction = (voltage_ratio * radians(360 - _frontend._dir_analog_deadzone)) + radians(_frontend._dir_analog_bearing_offset);
+
+    direction_update_frontend(wrap_PI(direction + AP::ahrs().yaw));
+}
+
+void AP_WindVane_Analog::calibrate()
+{
+
+    // start calibration
+    if (_cal_start_ms == 0) {
+        _cal_start_ms = AP_HAL::millis();
+        _cal_volt_max = _current_analog_voltage;
+        _cal_volt_min = _current_analog_voltage;
+        gcs().send_text(MAV_SEVERITY_INFO, "WindVane: Calibration started, rotate wind vane");
+    }
+
+    // record min and max voltage
+    _cal_volt_max = MAX(_cal_volt_max, _current_analog_voltage);
+    _cal_volt_min = MIN(_cal_volt_min, _current_analog_voltage);
+
+    // calibrate for 30 seconds
+    if ((AP_HAL::millis() - _cal_start_ms) > 30000) {
+        // check for required voltage difference
+        const float volt_diff = _cal_volt_max - _cal_volt_min;
+        if (volt_diff >= WINDVANE_CALIBRATION_VOLT_DIFF_MIN) {
+            // save min and max voltage
+            _frontend._dir_analog_volt_max.set_and_save(_cal_volt_max);
+            _frontend._dir_analog_volt_min.set_and_save(_cal_volt_min);
+            gcs().send_text(MAV_SEVERITY_INFO, "WindVane: Calibration complete (volt min:%.1f max:%1.f)",
+            (double)_cal_volt_min,
+            (double)_cal_volt_max);
+        } else {
+             gcs().send_text(MAV_SEVERITY_INFO, "WindVane: Calibration failed (volt diff %.1f below %.1f)",
+            (double)volt_diff,
+            (double)WINDVANE_CALIBRATION_VOLT_DIFF_MIN);
+        }
+        _frontend._calibration.set_and_save(0);
+        _cal_start_ms = 0;
+    }
+}
diff --git a/libraries/AP_WindVane/AP_WindVane_Analog.h b/libraries/AP_WindVane/AP_WindVane_Analog.h
new file mode 100644
index 0000000000..eed943835c
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_Analog.h
@@ -0,0 +1,42 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include "AP_WindVane_Backend.h"
+
+#include <GCS_MAVLink/GCS.h>
+#include <AP_HAL/AP_HAL.h>
+
+extern const AP_HAL::HAL& hal;
+
+class AP_WindVane_Analog : public AP_WindVane_Backend
+{
+public:
+    // constructor
+    AP_WindVane_Analog(AP_WindVane &frontend);
+
+    // update state
+    void update_direction() override;
+    void calibrate() override;
+
+private:
+    // pin for reading analog voltage
+    AP_HAL::AnalogSource *_dir_analog_source;
+
+    float _current_analog_voltage;
+    uint32_t  _cal_start_ms = 0;
+    float _cal_volt_min;
+    float _cal_volt_max;
+};
diff --git a/libraries/AP_WindVane/AP_WindVane_Backend.cpp b/libraries/AP_WindVane/AP_WindVane_Backend.cpp
new file mode 100644
index 0000000000..8452d4427a
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_Backend.cpp
@@ -0,0 +1,62 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "AP_WindVane.h"
+#include "AP_WindVane_Backend.h"
+
+// base class constructor.
+AP_WindVane_Backend::AP_WindVane_Backend(AP_WindVane &frontend) :
+        _frontend(frontend)
+{
+}
+
+// update speed to frontend
+void AP_WindVane_Backend::speed_update_frontend(float apparent_speed_in)
+{
+    // apply low pass filter if enabled
+    if (is_positive(_frontend._speed_filt_hz)) {
+        _speed_filt.set_cutoff_frequency(_frontend._speed_filt_hz);
+        _frontend._speed_apparent = _speed_filt.apply(apparent_speed_in, 0.02f);
+    } else {
+        _frontend._speed_apparent = apparent_speed_in;
+    }
+}
+
+// update direction to frontend
+void AP_WindVane_Backend::direction_update_frontend(float apparent_angle_ef)
+{
+    // apply low pass filter if enabled
+    if (is_positive(_frontend._dir_filt_hz)) {
+        _dir_sin_filt.set_cutoff_frequency(_frontend._dir_filt_hz);
+        _dir_cos_filt.set_cutoff_frequency(_frontend._dir_filt_hz);
+        // https://en.wikipedia.org/wiki/Mean_of_circular_quantities
+        const float filtered_sin = _dir_sin_filt.apply(sinf(apparent_angle_ef), 0.05f);
+        const float filtered_cos = _dir_cos_filt.apply(cosf(apparent_angle_ef), 0.05f);
+        _frontend._direction_apparent_ef = atan2f(filtered_sin, filtered_cos);
+    } else {
+        _frontend._direction_apparent_ef = apparent_angle_ef;
+    }
+
+    // make sure between -pi and pi
+    _frontend._direction_apparent_ef = wrap_PI(_frontend._direction_apparent_ef);
+}
+
+// calibrate WindVane
+void AP_WindVane_Backend::calibrate()
+{
+    gcs().send_text(MAV_SEVERITY_INFO, "WindVane: No cal required");
+    _frontend._calibration.set_and_save(0);
+    return;
+}
diff --git a/libraries/AP_WindVane/AP_WindVane_Backend.h b/libraries/AP_WindVane/AP_WindVane_Backend.h
new file mode 100644
index 0000000000..56e1d73138
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_Backend.h
@@ -0,0 +1,49 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include "AP_WindVane.h"
+
+#include <GCS_MAVLink/GCS.h>
+#include <Filter/Filter.h>
+
+class AP_WindVane_Backend
+{
+public:
+    // constructor. This incorporates initialization as well.
+    AP_WindVane_Backend(AP_WindVane &frontend);
+
+    // we declare a virtual destructor so that WindVane drivers can
+    // override with a custom destructor if need be
+    virtual ~AP_WindVane_Backend() {}
+
+    // update the state structure
+    virtual void update_speed() {};
+    virtual void update_direction() {};
+    virtual void calibrate();
+
+protected:
+    // update frontend
+    void speed_update_frontend(float apparent_speed_in);
+    void direction_update_frontend(float apparent_angle_ef);
+
+    AP_WindVane &_frontend;
+
+private:
+    // low pass filters of direction and speed
+    LowPassFilterFloat _dir_sin_filt = LowPassFilterFloat(2.0f);
+    LowPassFilterFloat _dir_cos_filt = LowPassFilterFloat(2.0f);
+    LowPassFilterFloat _speed_filt = LowPassFilterFloat(2.0f);
+};
diff --git a/libraries/AP_WindVane/AP_WindVane_Home.cpp b/libraries/AP_WindVane/AP_WindVane_Home.cpp
new file mode 100644
index 0000000000..d73b16bbd7
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_Home.cpp
@@ -0,0 +1,36 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "AP_WindVane_Home.h"
+
+// constructor
+AP_WindVane_Home::AP_WindVane_Home(AP_WindVane &frontend) :
+    AP_WindVane_Backend(frontend)
+{
+}
+
+void AP_WindVane_Home::update_direction()
+{
+    float direction_apparent_ef = _frontend._home_heading;
+
+    if (_frontend._direction_type == _frontend.WINDVANE_PWM_PIN && _frontend._rc_in_no != 0) {
+        RC_Channel *chan = rc().channel(_frontend._rc_in_no-1);
+        if (chan != nullptr) {
+            direction_apparent_ef = wrap_PI(direction_apparent_ef + chan->norm_input() * radians(45));
+        }
+    }
+
+    direction_update_frontend(direction_apparent_ef);
+}
diff --git a/libraries/AP_WindVane/AP_WindVane_Home.h b/libraries/AP_WindVane/AP_WindVane_Home.h
new file mode 100644
index 0000000000..7dc1271194
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_Home.h
@@ -0,0 +1,28 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include "AP_WindVane_Backend.h"
+#include <RC_Channel/RC_Channel.h>
+
+class AP_WindVane_Home : public AP_WindVane_Backend
+{
+public:
+    // constructor
+    AP_WindVane_Home(AP_WindVane &frontend);
+
+    // update state
+    void update_direction() override;
+};
diff --git a/libraries/AP_WindVane/AP_WindVane_ModernDevice.cpp b/libraries/AP_WindVane/AP_WindVane_ModernDevice.cpp
new file mode 100644
index 0000000000..b5bcc70ca8
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_ModernDevice.cpp
@@ -0,0 +1,54 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "AP_WindVane_ModernDevice.h"
+// read wind speed from Modern Device rev p wind sensor
+// https://moderndevice.com/news/calibrating-rev-p-wind-sensor-new-regression/
+
+// constructor
+AP_WindVane_ModernDevice::AP_WindVane_ModernDevice(AP_WindVane &frontend) :
+    AP_WindVane_Backend(frontend)
+{
+    _speed_analog_source = hal.analogin->channel(ANALOG_INPUT_NONE);
+    _temp_analog_source = hal.analogin->channel(ANALOG_INPUT_NONE);
+}
+
+void AP_WindVane_ModernDevice::update_speed()
+{
+    float analog_voltage = 0.0f;
+
+    // only read temp pin if defined, sensor will do OK assuming constant temp
+    float temp_ambient = 28.0f; // equations were generated at this temp in above data sheet
+    if (is_positive(_frontend._speed_sensor_temp_pin.get())) {
+        _temp_analog_source->set_pin(_frontend._speed_sensor_temp_pin.get());
+        analog_voltage = _temp_analog_source->voltage_average();
+        temp_ambient = (analog_voltage - 0.4f) / 0.0195f; // deg C
+        // constrain to reasonable range to avoid deviating from calibration too much and potential divide by zero
+        temp_ambient = constrain_float(temp_ambient, 10.0f, 40.0f);
+    }
+
+    _speed_analog_source->set_pin(_frontend._speed_sensor_speed_pin.get());
+    _current_analog_voltage = _speed_analog_source->voltage_average();
+
+    // apply voltage offset and make sure not negative
+    // by default the voltage offset is the number provide by the manufacturer
+    analog_voltage = _current_analog_voltage - _frontend._speed_sensor_voltage_offset;
+    if (is_negative(analog_voltage)) {
+        analog_voltage = 0.0f;
+    }
+
+    // simplified equation from data sheet, converted from mph to m/s
+    speed_update_frontend(24.254896f * powf((analog_voltage / powf(temp_ambient, 0.115157f)), 3.009364f));
+}
diff --git a/libraries/AP_WindVane/AP_WindVane_ModernDevice.h b/libraries/AP_WindVane/AP_WindVane_ModernDevice.h
new file mode 100644
index 0000000000..66b2e8c5c2
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_ModernDevice.h
@@ -0,0 +1,40 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include "AP_WindVane_Backend.h"
+
+#include <GCS_MAVLink/GCS.h>
+#include <AP_HAL/AP_HAL.h>
+
+extern const AP_HAL::HAL& hal;
+
+class AP_WindVane_ModernDevice : public AP_WindVane_Backend
+{
+public:
+    // constructor
+    AP_WindVane_ModernDevice(AP_WindVane &frontend);
+
+    // update state
+    void update_speed() override;
+    void calibrate() override;
+
+private:
+    float _current_analog_voltage;
+
+    // pin for reading analog voltage
+    AP_HAL::AnalogSource *_speed_analog_source;
+    AP_HAL::AnalogSource *_temp_analog_source;
+};
diff --git a/libraries/AP_WindVane/AP_WindVane_RPM.cpp b/libraries/AP_WindVane/AP_WindVane_RPM.cpp
new file mode 100644
index 0000000000..311d645dee
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_RPM.cpp
@@ -0,0 +1,33 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "AP_WindVane_RPM.h"
+
+// constructor
+AP_WindVane_RPM::AP_WindVane_RPM(AP_WindVane &frontend) :
+    AP_WindVane_Backend(frontend)
+{
+}
+
+void AP_WindVane_RPM::update_speed()
+{
+    const AP_RPM* rpm = AP_RPM::get_singleton();
+    if (rpm != nullptr) {
+        const float temp_speed = rpm->get_rpm(0);
+        if (!is_negative(temp_speed)) {
+            speed_update_frontend(temp_speed);
+        }
+    }
+}
diff --git a/libraries/AP_WindVane/AP_WindVane_RPM.h b/libraries/AP_WindVane/AP_WindVane_RPM.h
new file mode 100644
index 0000000000..aa79c23680
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_RPM.h
@@ -0,0 +1,29 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include "AP_WindVane_Backend.h"
+
+#include <AP_RPM/AP_RPM.h>
+
+class AP_WindVane_RPM : public AP_WindVane_Backend
+{
+public:
+    // constructor
+    AP_WindVane_RPM(AP_WindVane &frontend);
+
+    // update state
+    void update_speed() override;
+};
diff --git a/libraries/AP_WindVane/AP_WindVane_SITL.cpp b/libraries/AP_WindVane/AP_WindVane_SITL.cpp
new file mode 100644
index 0000000000..1031a8b32b
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_SITL.cpp
@@ -0,0 +1,60 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "AP_WindVane_SITL.h"
+
+// constructor
+AP_WindVane_SITL::AP_WindVane_SITL(AP_WindVane &frontend) :
+    AP_WindVane_Backend(frontend)
+{
+}
+
+#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
+
+void AP_WindVane_SITL::update_direction()
+{
+    // temporarily store true speed and direction for easy access
+    const float wind_speed = AP::sitl()->wind_speed_active;
+    const float wind_dir_rad = radians(AP::sitl()->wind_direction_active);
+
+    // Note than the SITL wind direction is defined as the direction the wind is traveling to
+    // This is accounted for in these calculations
+
+    // convert true wind speed and direction into a 2D vector
+    Vector2f wind_vector_ef(cosf(wind_dir_rad) * wind_speed, sinf(wind_dir_rad) * wind_speed);
+
+    // add vehicle speed to get apparent wind vector
+    wind_vector_ef.x += AP::sitl()->state.speedN;
+    wind_vector_ef.y += AP::sitl()->state.speedE;
+
+    direction_update_frontend(atan2f(wind_vector_ef.y, wind_vector_ef.x));
+}
+
+void AP_WindVane_SITL::update_speed()
+{
+    // temporarily store true speed and direction for easy access
+    const float wind_speed = AP::sitl()->wind_speed_active;
+    const float wind_dir_rad = radians(AP::sitl()->wind_direction_active);
+
+    // convert true wind speed and direction into a 2D vector
+    Vector2f wind_vector_ef(cosf(wind_dir_rad) * wind_speed, sinf(wind_dir_rad) * wind_speed);
+
+    // add vehicle speed to get apparent wind vector
+    wind_vector_ef.x += AP::sitl()->state.speedN;
+    wind_vector_ef.y += AP::sitl()->state.speedE;
+
+    speed_update_frontend(wind_vector_ef.length());
+}
+#endif
diff --git a/libraries/AP_WindVane/AP_WindVane_SITL.h b/libraries/AP_WindVane/AP_WindVane_SITL.h
new file mode 100644
index 0000000000..86d07b857d
--- /dev/null
+++ b/libraries/AP_WindVane/AP_WindVane_SITL.h
@@ -0,0 +1,30 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include "AP_WindVane_Backend.h"
+
+class AP_WindVane_SITL : public AP_WindVane_Backend
+{
+public:
+    // constructor
+    AP_WindVane_SITL(AP_WindVane &frontend);
+
+    // update state
+    #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
+        void update_direction() override;
+        void update_speed() override;
+    #endif
+};