From d691333e82ff74358450dc333e3cb577bf8e2461 Mon Sep 17 00:00:00 2001
From: shota <miyafly7@gmail.com>
Date: Fri, 26 Sep 2025 14:04:45 +0900
Subject: [PATCH 01/11] Add airspeed TPA support

---
 docs/Settings.md                              | 10 +++++
 src/main/fc/controlrate_profile.c             |  3 +-
 .../fc/controlrate_profile_config_struct.h    |  1 +
 src/main/fc/settings.yaml                     |  5 +++
 src/main/flight/pid.c                         | 37 ++++++++++---------
 src/main/sensors/pitotmeter.c                 |  9 +++++
 src/main/sensors/pitotmeter.h                 |  1 +
 7 files changed, 48 insertions(+), 18 deletions(-)

diff --git a/docs/Settings.md b/docs/Settings.md
index 256dd05a005..afab765a87d 100644
--- a/docs/Settings.md
+++ b/docs/Settings.md
@@ -302,6 +302,16 @@ ADC channel to use for analog pitot tube (airspeed) sensor. If board doesn't hav
 
 ---
 
+### airspeed_tpa
+
+Use airspeed instead of throttle position for TPA if airspeed is available. use throttle as {tpa_breakpoint + (airspeed - fw_reference_airspeed)/fw_reference_airspeed * (tpa_breakpoint - ThrottleIdleValue(default:1150))} for TPA calculation
+
+| Default | Min | Max |
+| --- | --- | --- |
+| OFF | OFF | ON |
+
+---
+
 ### align_board_pitch
 
 Arbitrary board rotation in deci-degrees (0.1 degree), to allow mounting it sideways / upside down / rotated etc
diff --git a/src/main/fc/controlrate_profile.c b/src/main/fc/controlrate_profile.c
index c8b144e136c..42fd3129ce1 100644
--- a/src/main/fc/controlrate_profile.c
+++ b/src/main/fc/controlrate_profile.c
@@ -46,7 +46,8 @@ void pgResetFn_controlRateProfiles(controlRateConfig_t *instance)
                 .dynPID = SETTING_TPA_RATE_DEFAULT,
                 .dynPID_on_YAW = SETTING_TPA_ON_YAW_DEFAULT,
                 .pa_breakpoint = SETTING_TPA_BREAKPOINT_DEFAULT,
-                .fixedWingTauMs = SETTING_FW_TPA_TIME_CONSTANT_DEFAULT
+                .fixedWingTauMs = SETTING_FW_TPA_TIME_CONSTANT_DEFAULT,
+                .airspeed_tpa = SETTING_AIRSPEED_TPA_DEFAULT,
             },
 
             .stabilized = {
diff --git a/src/main/fc/controlrate_profile_config_struct.h b/src/main/fc/controlrate_profile_config_struct.h
index e4038537603..acd4e40926f 100644
--- a/src/main/fc/controlrate_profile_config_struct.h
+++ b/src/main/fc/controlrate_profile_config_struct.h
@@ -32,6 +32,7 @@ typedef struct controlRateConfig_s {
         bool dynPID_on_YAW;
         uint16_t pa_breakpoint;                // Breakpoint where TPA is activated
         uint16_t fixedWingTauMs;               // Time constant of airplane TPA PT1-filter
+        bool airspeed_tpa;                     // Use airspeed instead of throttle position for TPA calculation
     } throttle;
 
     struct {
diff --git a/src/main/fc/settings.yaml b/src/main/fc/settings.yaml
index 5fe29261630..a5593efaf03 100644
--- a/src/main/fc/settings.yaml
+++ b/src/main/fc/settings.yaml
@@ -1343,6 +1343,11 @@ groups:
         field: throttle.dynPID
         min: 0
         max: 100
+      - name: airspeed_tpa
+        description: "Use airspeed instead of throttle position for TPA if airspeed is available. use throttle as {tpa_breakpoint + (airspeed - fw_reference_airspeed)/fw_reference_airspeed * (tpa_breakpoint - ThrottleIdleValue(default:1150))} for TPA calculation"
+        type: bool
+        field: throttle.airspeed_tpa
+        default_value: OFF
       - name: tpa_breakpoint
         description: "See tpa_rate."
         default_value: 1500
diff --git a/src/main/flight/pid.c b/src/main/flight/pid.c
index ae8eb57fb30..f957073ccbd 100644
--- a/src/main/flight/pid.c
+++ b/src/main/flight/pid.c
@@ -469,15 +469,15 @@ static float calculateFixedWingTPAFactor(uint16_t throttle)
     return tpaFactor;
 }
 
-static float calculateMultirotorTPAFactor(void)
+static float calculateMultirotorTPAFactor(uint16_t throttle)
 {
     float tpaFactor;
 
     // TPA should be updated only when TPA is actually set
-    if (currentControlRateProfile->throttle.dynPID == 0 || rcCommand[THROTTLE] < currentControlRateProfile->throttle.pa_breakpoint) {
+    if (currentControlRateProfile->throttle.dynPID == 0 || throttle < currentControlRateProfile->throttle.pa_breakpoint) {
         tpaFactor = 1.0f;
-    } else if (rcCommand[THROTTLE] < getMaxThrottle()) {
-        tpaFactor = (100 - (uint16_t)currentControlRateProfile->throttle.dynPID * (rcCommand[THROTTLE] - currentControlRateProfile->throttle.pa_breakpoint) / (float)(getMaxThrottle() - currentControlRateProfile->throttle.pa_breakpoint)) / 100.0f;
+    } else if (throttle < getMaxThrottle()) {
+        tpaFactor = (100 - (uint16_t)currentControlRateProfile->throttle.dynPID * (throttle - currentControlRateProfile->throttle.pa_breakpoint) / (float)(getMaxThrottle() - currentControlRateProfile->throttle.pa_breakpoint)) / 100.0f;
     } else {
         tpaFactor = (100 - currentControlRateProfile->throttle.dynPID) / 100.0f;
     }
@@ -493,20 +493,24 @@ void schedulePidGainsUpdate(void)
 void updatePIDCoefficients(void)
 {
     STATIC_FASTRAM uint16_t prevThrottle = 0;
+    STATIC_FASTRAM uint16_t tpaThrottle = 0;
 
-    // Check if throttle changed. Different logic for fixed wing vs multirotor
-    if (usedPidControllerType == PID_TYPE_PIFF && (currentControlRateProfile->throttle.fixedWingTauMs > 0)) {
-        uint16_t filteredThrottle = pt1FilterApply(&fixedWingTpaFilter, rcCommand[THROTTLE]);
-        if (filteredThrottle != prevThrottle) {
-            prevThrottle = filteredThrottle;
-            pidGainsUpdateRequired = true;
-        }
+    if (usedPidControllerType == PID_TYPE_PIFF && pitotValidForAirspeed() && currentControlRateProfile->throttle.airspeed_tpa) {
+        // Use airspeed instead of throttle for TPA calculation
+        const float airspeed = getAirspeedEstimate(); // in cm/s
+        const float referenceAirspeed = pidProfile()->fixedWingReferenceAirspeed; // in cm/s
+        tpaThrottle = currentControlRateProfile->throttle.pa_breakpoint + (uint16_t)((airspeed - referenceAirspeed) / referenceAirspeed * (currentControlRateProfile->throttle.pa_breakpoint - getThrottleIdleValue()));
+        //upper and lower limits will be applied in calculateFixedWingTPAFactor()
+    }
+    else if (usedPidControllerType == PID_TYPE_PIFF && (currentControlRateProfile->throttle.fixedWingTauMs > 0)) {
+        tpaThrottle = pt1FilterApply(&fixedWingTpaFilter, rcCommand[THROTTLE]);
     }
     else {
-        if (rcCommand[THROTTLE] != prevThrottle) {
-            prevThrottle = rcCommand[THROTTLE];
-            pidGainsUpdateRequired = true;
-        }
+        tpaThrottle = rcCommand[THROTTLE];
+    }
+    if (tpaThrottle != prevThrottle) {
+        prevThrottle = tpaThrottle;
+        pidGainsUpdateRequired = true;
     }
 
 #ifdef USE_ANTIGRAVITY
@@ -528,8 +532,7 @@ void updatePIDCoefficients(void)
         return;
     }
 
-    const float tpaFactor = usedPidControllerType == PID_TYPE_PIFF ? calculateFixedWingTPAFactor(prevThrottle) : calculateMultirotorTPAFactor();
-
+    const float tpaFactor = usedPidControllerType == PID_TYPE_PIFF ? calculateFixedWingTPAFactor(prevThrottle) : calculateMultirotorTPAFactor(prevThrottle);
     // PID coefficients can be update only with THROTTLE and TPA or inflight PID adjustments
     //TODO: Next step would be to update those only at THROTTLE or inflight adjustments change
     for (int axis = 0; axis < 3; axis++) {
diff --git a/src/main/sensors/pitotmeter.c b/src/main/sensors/pitotmeter.c
index baf7bed0a61..cb5b9f76f9a 100755
--- a/src/main/sensors/pitotmeter.c
+++ b/src/main/sensors/pitotmeter.c
@@ -305,4 +305,13 @@ bool pitotIsHealthy(void)
     return (millis() - pitot.lastSeenHealthyMs) < PITOT_HARDWARE_TIMEOUT_MS;
 }
 
+bool pitotValidForAirspeed(void)
+{
+    bool ret = false;
+    ret = pitotIsHealthy() && pitotIsCalibrationComplete();
+    if (detectedSensors[SENSOR_INDEX_PITOT] == PITOT_VIRTUAL) {
+        ret = ret && STATE(GPS_FIX);
+    }
+    return ret;
+}
 #endif /* PITOT */
diff --git a/src/main/sensors/pitotmeter.h b/src/main/sensors/pitotmeter.h
index aed924f8e4c..68f5a9c1a02 100755
--- a/src/main/sensors/pitotmeter.h
+++ b/src/main/sensors/pitotmeter.h
@@ -69,5 +69,6 @@ void pitotStartCalibration(void);
 void pitotUpdate(void);
 float getAirspeedEstimate(void);
 bool pitotIsHealthy(void);
+bool pitotValidForAirspeed(void);
 
 #endif

From 6bc321b773c41ee928f62d5994b8e2e1345f4e20 Mon Sep 17 00:00:00 2001
From: shota <miyafly7@gmail.com>
Date: Sat, 27 Sep 2025 19:10:17 +0900
Subject: [PATCH 02/11] minor fix

---
 src/main/flight/pid.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/flight/pid.c b/src/main/flight/pid.c
index f957073ccbd..a85d9bf6bab 100644
--- a/src/main/flight/pid.c
+++ b/src/main/flight/pid.c
@@ -500,7 +500,7 @@ void updatePIDCoefficients(void)
         const float airspeed = getAirspeedEstimate(); // in cm/s
         const float referenceAirspeed = pidProfile()->fixedWingReferenceAirspeed; // in cm/s
         tpaThrottle = currentControlRateProfile->throttle.pa_breakpoint + (uint16_t)((airspeed - referenceAirspeed) / referenceAirspeed * (currentControlRateProfile->throttle.pa_breakpoint - getThrottleIdleValue()));
-        //upper and lower limits will be applied in calculateFixedWingTPAFactor()
+        tpaThrottle = constrain(tpaThrottle, getThrottleIdleValue(), tpaThrottle);
     }
     else if (usedPidControllerType == PID_TYPE_PIFF && (currentControlRateProfile->throttle.fixedWingTauMs > 0)) {
         tpaThrottle = pt1FilterApply(&fixedWingTpaFilter, rcCommand[THROTTLE]);

From c1e211205d107293bbad9632af4721f46d918880 Mon Sep 17 00:00:00 2001
From: shota <miyafly7@gmail.com>
Date: Thu, 6 Nov 2025 10:44:51 +0900
Subject: [PATCH 03/11] airspeed tpa

---
 docs/Settings.md                              |  6 +-
 src/main/fc/controlrate_profile.c             |  2 +-
 .../fc/controlrate_profile_config_struct.h    |  2 +-
 src/main/fc/settings.yaml                     | 12 ++--
 src/main/flight/pid.c                         | 60 ++++++++++++-------
 5 files changed, 51 insertions(+), 31 deletions(-)

diff --git a/docs/Settings.md b/docs/Settings.md
index afab765a87d..aea055fb937 100644
--- a/docs/Settings.md
+++ b/docs/Settings.md
@@ -302,13 +302,13 @@ ADC channel to use for analog pitot tube (airspeed) sensor. If board doesn't hav
 
 ---
 
-### airspeed_tpa
+### airspeed_tpa_pow
 
-Use airspeed instead of throttle position for TPA if airspeed is available. use throttle as {tpa_breakpoint + (airspeed - fw_reference_airspeed)/fw_reference_airspeed * (tpa_breakpoint - ThrottleIdleValue(default:1150))} for TPA calculation
+Use airspeed instead of throttle position for TPA if airspeed is available on fixedwing. pid_multiplier(tpa_factor) = (referenceAirspeed/airspeed)**(airspeed_tpa_pow/100). Set to 0 will disable this feature and use throttle based tpa;
 
 | Default | Min | Max |
 | --- | --- | --- |
-| OFF | OFF | ON |
+| 120 | 0 | 200 |
 
 ---
 
diff --git a/src/main/fc/controlrate_profile.c b/src/main/fc/controlrate_profile.c
index 42fd3129ce1..1c2d632d9ce 100644
--- a/src/main/fc/controlrate_profile.c
+++ b/src/main/fc/controlrate_profile.c
@@ -47,7 +47,7 @@ void pgResetFn_controlRateProfiles(controlRateConfig_t *instance)
                 .dynPID_on_YAW = SETTING_TPA_ON_YAW_DEFAULT,
                 .pa_breakpoint = SETTING_TPA_BREAKPOINT_DEFAULT,
                 .fixedWingTauMs = SETTING_FW_TPA_TIME_CONSTANT_DEFAULT,
-                .airspeed_tpa = SETTING_AIRSPEED_TPA_DEFAULT,
+                .airspeed_tpa_pow = SETTING_AIRSPEED_TPA_POW_DEFAULT,
             },
 
             .stabilized = {
diff --git a/src/main/fc/controlrate_profile_config_struct.h b/src/main/fc/controlrate_profile_config_struct.h
index acd4e40926f..8c4e57b7f1f 100644
--- a/src/main/fc/controlrate_profile_config_struct.h
+++ b/src/main/fc/controlrate_profile_config_struct.h
@@ -32,7 +32,7 @@ typedef struct controlRateConfig_s {
         bool dynPID_on_YAW;
         uint16_t pa_breakpoint;                // Breakpoint where TPA is activated
         uint16_t fixedWingTauMs;               // Time constant of airplane TPA PT1-filter
-        bool airspeed_tpa;                     // Use airspeed instead of throttle position for TPA calculation
+        uint16_t airspeed_tpa_pow;                     // Use airspeed instead of throttle position for TPA calculation,0 to disable
     } throttle;
 
     struct {
diff --git a/src/main/fc/settings.yaml b/src/main/fc/settings.yaml
index a5593efaf03..1b14b82d580 100644
--- a/src/main/fc/settings.yaml
+++ b/src/main/fc/settings.yaml
@@ -1337,17 +1337,19 @@ groups:
         field: throttle.rcExpo8
         min: 0
         max: 100
+      - name: airspeed_tpa_pow
+        description: "Use airspeed instead of throttle position for TPA if airspeed is available on fixedwing. pid_multiplier(tpa_factor) = (referenceAirspeed/airspeed)**(airspeed_tpa_pow/100). Set to 0 will disable this feature and use throttle based tpa;"
+        type: uint16_t
+        field: throttle.airspeed_tpa_pow
+        default_value: 120
+        min: 0
+        max: 200
       - name: tpa_rate
         description: "Throttle PID attenuation reduces influence of PDFF on ROLL and PITCH of multi-rotor, PIDFF on ROLL,PITCH,YAW OF fixed_wing as throttle increases. For every 1% throttle after the TPA breakpoint, P is reduced by the TPA rate."
         default_value: 0
         field: throttle.dynPID
         min: 0
         max: 100
-      - name: airspeed_tpa
-        description: "Use airspeed instead of throttle position for TPA if airspeed is available. use throttle as {tpa_breakpoint + (airspeed - fw_reference_airspeed)/fw_reference_airspeed * (tpa_breakpoint - ThrottleIdleValue(default:1150))} for TPA calculation"
-        type: bool
-        field: throttle.airspeed_tpa
-        default_value: OFF
       - name: tpa_breakpoint
         description: "See tpa_rate."
         default_value: 1500
diff --git a/src/main/flight/pid.c b/src/main/flight/pid.c
index a85d9bf6bab..9b85d413e69 100644
--- a/src/main/flight/pid.c
+++ b/src/main/flight/pid.c
@@ -441,6 +441,14 @@ float pidRcCommandToRate(int16_t stick, uint8_t rate)
     return scaleRangef((float) stick, -500.0f, 500.0f, -maxRateDPS, maxRateDPS);
 }
 
+static float calculateFixedWingAirspeedTPAFactor(void){
+    const float airspeed = getAirspeedEstimate(); // in cm/s
+    const float referenceAirspeed = pidProfile()->fixedWingReferenceAirspeed; // in cm/s
+    float tpaFactor= powf(referenceAirspeed/(airspeed+0.01f), currentControlRateProfile->throttle.airspeed_tpa_pow/100.0f);
+    tpaFactor= constrainf(tpaFactor, 0.3f, 2.0f);
+    return tpaFactor;
+}
+
 static float calculateFixedWingTPAFactor(uint16_t throttle)
 {
     float tpaFactor;
@@ -485,6 +493,19 @@ static float calculateMultirotorTPAFactor(uint16_t throttle)
     return tpaFactor;
 }
 
+static float calculateTPAThtrottle(void)
+{
+    uint16_t tpaThrottle = 0;
+
+    if (usedPidControllerType == PID_TYPE_PIFF && (currentControlRateProfile->throttle.fixedWingTauMs > 0)) { //fixed wing TPA with filtering
+        tpaThrottle = pt1FilterApply(&fixedWingTpaFilter, rcCommand[THROTTLE]);
+    }
+    else {
+        tpaThrottle = rcCommand[THROTTLE]; //multirotor TPA without filtering
+    }
+    return tpaThrottle;
+}
+
 void schedulePidGainsUpdate(void)
 {
     pidGainsUpdateRequired = true;
@@ -492,26 +513,7 @@ void schedulePidGainsUpdate(void)
 
 void updatePIDCoefficients(void)
 {
-    STATIC_FASTRAM uint16_t prevThrottle = 0;
-    STATIC_FASTRAM uint16_t tpaThrottle = 0;
-
-    if (usedPidControllerType == PID_TYPE_PIFF && pitotValidForAirspeed() && currentControlRateProfile->throttle.airspeed_tpa) {
-        // Use airspeed instead of throttle for TPA calculation
-        const float airspeed = getAirspeedEstimate(); // in cm/s
-        const float referenceAirspeed = pidProfile()->fixedWingReferenceAirspeed; // in cm/s
-        tpaThrottle = currentControlRateProfile->throttle.pa_breakpoint + (uint16_t)((airspeed - referenceAirspeed) / referenceAirspeed * (currentControlRateProfile->throttle.pa_breakpoint - getThrottleIdleValue()));
-        tpaThrottle = constrain(tpaThrottle, getThrottleIdleValue(), tpaThrottle);
-    }
-    else if (usedPidControllerType == PID_TYPE_PIFF && (currentControlRateProfile->throttle.fixedWingTauMs > 0)) {
-        tpaThrottle = pt1FilterApply(&fixedWingTpaFilter, rcCommand[THROTTLE]);
-    }
-    else {
-        tpaThrottle = rcCommand[THROTTLE];
-    }
-    if (tpaThrottle != prevThrottle) {
-        prevThrottle = tpaThrottle;
-        pidGainsUpdateRequired = true;
-    }
+    STATIC_FASTRAM float tpaFactorprev=1.0f;
 
 #ifdef USE_ANTIGRAVITY
     if (usedPidControllerType == PID_TYPE_PID) {
@@ -526,13 +528,29 @@ void updatePIDCoefficients(void)
     for (int axis = 0; axis < 3; axis++) {
         pidState[axis].stickPosition = constrain(rxGetChannelValue(axis) - PWM_RANGE_MIDDLE, -500, 500) / 500.0f;
     }
+    
+    float tpaFactor=1.0f;
+    if(usedPidControllerType == PID_TYPE_PIFF){ // Fixed wing TPA calculation
+        if(currentControlRateProfile->throttle.airspeed_tpa_pow>0){
+            tpaFactor = calculateFixedWingAirspeedTPAFactor();
+        }else{
+            tpaFactor = calculateFixedWingTPAFactor(calculateTPAThtrottle());
+        }
+    } else {
+        tpaFactor = calculateMultirotorTPAFactor(calculateTPAThtrottle());
+    }
+    if (tpaFactor != tpaFactorprev) {
+        pidGainsUpdateRequired = true;
+    }
+    tpaFactorprev = tpaFactor;
 
+    
     // If nothing changed - don't waste time recalculating coefficients
     if (!pidGainsUpdateRequired) {
         return;
     }
 
-    const float tpaFactor = usedPidControllerType == PID_TYPE_PIFF ? calculateFixedWingTPAFactor(prevThrottle) : calculateMultirotorTPAFactor(prevThrottle);
+    
     // PID coefficients can be update only with THROTTLE and TPA or inflight PID adjustments
     //TODO: Next step would be to update those only at THROTTLE or inflight adjustments change
     for (int axis = 0; axis < 3; axis++) {

From 4c44d5f01227a810e8a9873b9024d06210915c2d Mon Sep 17 00:00:00 2001
From: shota <miyafly7@gmail.com>
Date: Thu, 6 Nov 2025 12:02:22 +0900
Subject: [PATCH 04/11] Initialize pidGainsUpdateRequired to true for proper
 PID gain updates

---
 src/main/flight/pid.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/main/flight/pid.c b/src/main/flight/pid.c
index 9b85d413e69..a35b5add72a 100644
--- a/src/main/flight/pid.c
+++ b/src/main/flight/pid.c
@@ -126,7 +126,7 @@ static EXTENDED_FASTRAM pt1Filter_t headingHoldRateFilter;
 static EXTENDED_FASTRAM pt1Filter_t fixedWingTpaFilter;
 
 // Thrust PID Attenuation factor. 0.0f means fully attenuated, 1.0f no attenuation is applied
-STATIC_FASTRAM bool pidGainsUpdateRequired;
+STATIC_FASTRAM bool pidGainsUpdateRequired= true;
 FASTRAM int16_t axisPID[FLIGHT_DYNAMICS_INDEX_COUNT];
 
 #ifdef USE_BLACKBOX
@@ -513,7 +513,7 @@ void schedulePidGainsUpdate(void)
 
 void updatePIDCoefficients(void)
 {
-    STATIC_FASTRAM float tpaFactorprev=1.0f;
+    STATIC_FASTRAM float tpaFactorprev=-1.0f;
 
 #ifdef USE_ANTIGRAVITY
     if (usedPidControllerType == PID_TYPE_PID) {

From 960336143959958364cbf44586d0f17f5509a1cd Mon Sep 17 00:00:00 2001
From: shota <miyafly7@gmail.com>
Date: Thu, 6 Nov 2025 12:13:59 +0900
Subject: [PATCH 05/11] raise pitot_lpf_milli_hz

---
 docs/Settings.md          | 2 +-
 src/main/fc/settings.yaml | 2 +-
 src/main/flight/pid.c     | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/docs/Settings.md b/docs/Settings.md
index aea055fb937..193cc38485a 100644
--- a/docs/Settings.md
+++ b/docs/Settings.md
@@ -5578,7 +5578,7 @@ Pitot tube lowpass filter cutoff frequency. Lower cutoff frequencies result in s
 
 | Default | Min | Max |
 | --- | --- | --- |
-| 350 | 0 | 10000 |
+| 1000 | 0 | 10000 |
 
 ---
 
diff --git a/src/main/fc/settings.yaml b/src/main/fc/settings.yaml
index 1b14b82d580..d5a80e745d3 100644
--- a/src/main/fc/settings.yaml
+++ b/src/main/fc/settings.yaml
@@ -656,7 +656,7 @@ groups:
         description: "Pitot tube lowpass filter cutoff frequency. Lower cutoff frequencies result in smoother response at expense of command control delay"
         min: 0
         max: 10000
-        default_value: 350
+        default_value: 1000
       - name: pitot_scale
         description: "Pitot tube scale factor"
         min: 0
diff --git a/src/main/flight/pid.c b/src/main/flight/pid.c
index a35b5add72a..14a78ea7842 100644
--- a/src/main/flight/pid.c
+++ b/src/main/flight/pid.c
@@ -531,7 +531,7 @@ void updatePIDCoefficients(void)
     
     float tpaFactor=1.0f;
     if(usedPidControllerType == PID_TYPE_PIFF){ // Fixed wing TPA calculation
-        if(currentControlRateProfile->throttle.airspeed_tpa_pow>0){
+        if(currentControlRateProfile->throttle.airspeed_tpa_pow>0 && pitotValidForAirspeed()){
             tpaFactor = calculateFixedWingAirspeedTPAFactor();
         }else{
             tpaFactor = calculateFixedWingTPAFactor(calculateTPAThtrottle());

From 00c9db0f46d4c0bc28a750007d9a2b060e0bcf02 Mon Sep 17 00:00:00 2001
From: shota hayashi <miyafly7@gmail.com>
Date: Mon, 17 Nov 2025 02:15:19 +0900
Subject: [PATCH 06/11] enhance tpa with pitch angle aware

---
 docs/Settings.md                              | 22 +++++++++----------
 src/main/fc/controlrate_profile.c             |  2 +-
 .../fc/controlrate_profile_config_struct.h    |  2 +-
 src/main/fc/settings.yaml                     |  8 +++----
 src/main/flight/pid.c                         | 11 +++++++---
 5 files changed, 25 insertions(+), 20 deletions(-)

diff --git a/docs/Settings.md b/docs/Settings.md
index 193cc38485a..7cc99c94e7a 100644
--- a/docs/Settings.md
+++ b/docs/Settings.md
@@ -302,16 +302,6 @@ ADC channel to use for analog pitot tube (airspeed) sensor. If board doesn't hav
 
 ---
 
-### airspeed_tpa_pow
-
-Use airspeed instead of throttle position for TPA if airspeed is available on fixedwing. pid_multiplier(tpa_factor) = (referenceAirspeed/airspeed)**(airspeed_tpa_pow/100). Set to 0 will disable this feature and use throttle based tpa;
-
-| Default | Min | Max |
-| --- | --- | --- |
-| 120 | 0 | 200 |
-
----
-
 ### align_board_pitch
 
 Arbitrary board rotation in deci-degrees (0.1 degree), to allow mounting it sideways / upside down / rotated etc
@@ -432,6 +422,16 @@ Max Antigravity gain. `1` means Antigravity is disabled, `2` means Iterm is allo
 
 ---
 
+### apa_pow
+
+Use airspeed instead of throttle position for PID attenuation if airspeed is available on fixedwing. pid_multiplier = (referenceAirspeed/airspeed)**(apa_pow/100). Set to 0 will disable this feature and use throttle based PID attenuation;
+
+| Default | Min | Max |
+| --- | --- | --- |
+| 120 | 0 | 200 |
+
+---
+
 ### applied_defaults
 
 Internal (configurator) hint. Should not be changed manually
@@ -6394,7 +6394,7 @@ Throttle PID attenuation also reduces influence on YAW for multi-rotor, Should b
 
 ### tpa_rate
 
-Throttle PID attenuation reduces influence of PDFF on ROLL and PITCH of multi-rotor, PIDFF on ROLL,PITCH,YAW OF fixed_wing as throttle increases. For every 1% throttle after the TPA breakpoint, P is reduced by the TPA rate.
+Throttle based PID attenuation(TPA) reduces influence of PDFF on ROLL and PITCH of multi-rotor, PIDFF on ROLL,PITCH,YAW OF fixed_wing as throttle increases. For every 1% throttle after the TPA breakpoint, P is reduced by the TPA rate.
 
 | Default | Min | Max |
 | --- | --- | --- |
diff --git a/src/main/fc/controlrate_profile.c b/src/main/fc/controlrate_profile.c
index 1c2d632d9ce..a7794e47eed 100644
--- a/src/main/fc/controlrate_profile.c
+++ b/src/main/fc/controlrate_profile.c
@@ -47,7 +47,7 @@ void pgResetFn_controlRateProfiles(controlRateConfig_t *instance)
                 .dynPID_on_YAW = SETTING_TPA_ON_YAW_DEFAULT,
                 .pa_breakpoint = SETTING_TPA_BREAKPOINT_DEFAULT,
                 .fixedWingTauMs = SETTING_FW_TPA_TIME_CONSTANT_DEFAULT,
-                .airspeed_tpa_pow = SETTING_AIRSPEED_TPA_POW_DEFAULT,
+                .apa_pow = SETTING_APA_POW_DEFAULT,
             },
 
             .stabilized = {
diff --git a/src/main/fc/controlrate_profile_config_struct.h b/src/main/fc/controlrate_profile_config_struct.h
index 8c4e57b7f1f..2ac4aa421ee 100644
--- a/src/main/fc/controlrate_profile_config_struct.h
+++ b/src/main/fc/controlrate_profile_config_struct.h
@@ -32,7 +32,7 @@ typedef struct controlRateConfig_s {
         bool dynPID_on_YAW;
         uint16_t pa_breakpoint;                // Breakpoint where TPA is activated
         uint16_t fixedWingTauMs;               // Time constant of airplane TPA PT1-filter
-        uint16_t airspeed_tpa_pow;                     // Use airspeed instead of throttle position for TPA calculation,0 to disable
+        uint16_t apa_pow;                     // Use airspeed instead of throttle position for TPA calculation,0 to disable
     } throttle;
 
     struct {
diff --git a/src/main/fc/settings.yaml b/src/main/fc/settings.yaml
index d5a80e745d3..7ff9c3b7a6e 100644
--- a/src/main/fc/settings.yaml
+++ b/src/main/fc/settings.yaml
@@ -1337,15 +1337,15 @@ groups:
         field: throttle.rcExpo8
         min: 0
         max: 100
-      - name: airspeed_tpa_pow
-        description: "Use airspeed instead of throttle position for TPA if airspeed is available on fixedwing. pid_multiplier(tpa_factor) = (referenceAirspeed/airspeed)**(airspeed_tpa_pow/100). Set to 0 will disable this feature and use throttle based tpa;"
+      - name: apa_pow
+        description: "Use airspeed instead of throttle position for PID attenuation if airspeed is available on fixedwing. pid_multiplier = (referenceAirspeed/airspeed)**(apa_pow/100). Set to 0 will disable this feature and use throttle based PID attenuation;"
         type: uint16_t
-        field: throttle.airspeed_tpa_pow
+        field: throttle.apa_pow
         default_value: 120
         min: 0
         max: 200
       - name: tpa_rate
-        description: "Throttle PID attenuation reduces influence of PDFF on ROLL and PITCH of multi-rotor, PIDFF on ROLL,PITCH,YAW OF fixed_wing as throttle increases. For every 1% throttle after the TPA breakpoint, P is reduced by the TPA rate."
+        description: "Throttle based PID attenuation(TPA) reduces influence of PDFF on ROLL and PITCH of multi-rotor, PIDFF on ROLL,PITCH,YAW OF fixed_wing as throttle increases. For every 1% throttle after the TPA breakpoint, P is reduced by the TPA rate."
         default_value: 0
         field: throttle.dynPID
         min: 0
diff --git a/src/main/flight/pid.c b/src/main/flight/pid.c
index 14a78ea7842..061646840b4 100644
--- a/src/main/flight/pid.c
+++ b/src/main/flight/pid.c
@@ -444,7 +444,7 @@ float pidRcCommandToRate(int16_t stick, uint8_t rate)
 static float calculateFixedWingAirspeedTPAFactor(void){
     const float airspeed = getAirspeedEstimate(); // in cm/s
     const float referenceAirspeed = pidProfile()->fixedWingReferenceAirspeed; // in cm/s
-    float tpaFactor= powf(referenceAirspeed/(airspeed+0.01f), currentControlRateProfile->throttle.airspeed_tpa_pow/100.0f);
+    float tpaFactor= powf(referenceAirspeed/(airspeed+0.01f), currentControlRateProfile->throttle.apa_pow/100.0f);
     tpaFactor= constrainf(tpaFactor, 0.3f, 2.0f);
     return tpaFactor;
 }
@@ -496,9 +496,14 @@ static float calculateMultirotorTPAFactor(uint16_t throttle)
 static float calculateTPAThtrottle(void)
 {
     uint16_t tpaThrottle = 0;
+    static const fpVector3_t vDown = { .v = { 0.0f, 0.0f, 1.0f } };
 
     if (usedPidControllerType == PID_TYPE_PIFF && (currentControlRateProfile->throttle.fixedWingTauMs > 0)) { //fixed wing TPA with filtering
-        tpaThrottle = pt1FilterApply(&fixedWingTpaFilter, rcCommand[THROTTLE]);
+        fpVector3_t vForward = { .v = { HeadVecEFFiltered.x, -HeadVecEFFiltered.y, -HeadVecEFFiltered.z } };
+        float groundCos = vectorDotProduct(&vForward, &vDown);
+        int16_t throttleAdjustment =  currentBatteryProfile->nav.fw.pitch_to_throttle * groundCos * 90.0f; // 90 degrees is to scale from cos to throttle adjustment
+        uint16_t throttleAdjusted = rcCommand[THROTTLE] + constrain(throttleAdjustment, -1000, 1000);
+        tpaThrottle = pt1FilterApply(&fixedWingTpaFilter, constrain(throttleAdjusted, 1000, 2000));
     }
     else {
         tpaThrottle = rcCommand[THROTTLE]; //multirotor TPA without filtering
@@ -531,7 +536,7 @@ void updatePIDCoefficients(void)
     
     float tpaFactor=1.0f;
     if(usedPidControllerType == PID_TYPE_PIFF){ // Fixed wing TPA calculation
-        if(currentControlRateProfile->throttle.airspeed_tpa_pow>0 && pitotValidForAirspeed()){
+        if(currentControlRateProfile->throttle.apa_pow>0 && pitotValidForAirspeed()){
             tpaFactor = calculateFixedWingAirspeedTPAFactor();
         }else{
             tpaFactor = calculateFixedWingTPAFactor(calculateTPAThtrottle());

From 89850d7fc31fa8c3e4c00648350a5d75891fe9a4 Mon Sep 17 00:00:00 2001
From: shota hayashi <miyafly7@gmail.com>
Date: Thu, 11 Dec 2025 01:03:03 +0900
Subject: [PATCH 07/11] update on tpa

---
 src/main/fc/controlrate_profile.c               |  1 +
 src/main/fc/controlrate_profile_config_struct.h |  1 +
 src/main/fc/settings.yaml                       | 10 ++++++++--
 src/main/flight/pid.c                           | 10 +++++-----
 4 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/src/main/fc/controlrate_profile.c b/src/main/fc/controlrate_profile.c
index a7794e47eed..d004908b72b 100644
--- a/src/main/fc/controlrate_profile.c
+++ b/src/main/fc/controlrate_profile.c
@@ -48,6 +48,7 @@ void pgResetFn_controlRateProfiles(controlRateConfig_t *instance)
                 .pa_breakpoint = SETTING_TPA_BREAKPOINT_DEFAULT,
                 .fixedWingTauMs = SETTING_FW_TPA_TIME_CONSTANT_DEFAULT,
                 .apa_pow = SETTING_APA_POW_DEFAULT,
+                .tpa_pitch_compensation = SETTING_TPA_PITCH_COMPENSATION_DEFAULT
             },
 
             .stabilized = {
diff --git a/src/main/fc/controlrate_profile_config_struct.h b/src/main/fc/controlrate_profile_config_struct.h
index 2ac4aa421ee..7f46fb57a83 100644
--- a/src/main/fc/controlrate_profile_config_struct.h
+++ b/src/main/fc/controlrate_profile_config_struct.h
@@ -33,6 +33,7 @@ typedef struct controlRateConfig_s {
         uint16_t pa_breakpoint;                // Breakpoint where TPA is activated
         uint16_t fixedWingTauMs;               // Time constant of airplane TPA PT1-filter
         uint16_t apa_pow;                     // Use airspeed instead of throttle position for TPA calculation,0 to disable
+        uint8_t tpa_pitch_compensation;      // Pitch angle based throttle compensation for fixed wing
     } throttle;
 
     struct {
diff --git a/src/main/fc/settings.yaml b/src/main/fc/settings.yaml
index 5e513b328f3..19dbb0ce5f6 100644
--- a/src/main/fc/settings.yaml
+++ b/src/main/fc/settings.yaml
@@ -1387,17 +1387,23 @@ groups:
         min: 0
         max: 200
       - name: tpa_rate
-        description: "Throttle based PID attenuation(TPA) reduces influence of PDFF on ROLL and PITCH of multi-rotor, PIDFF on ROLL,PITCH,YAW OF fixed_wing as throttle increases. For every 1% throttle after the TPA breakpoint, P is reduced by the TPA rate."
+        description: "Throttle based PID attenuation(TPA) reduces influence of PDFF on ROLL and PITCH of multi-rotor, PIDFF on ROLL,PITCH,YAW OF fixed_wing as throttle increases. On multirotor, For every 1% throttle after the TPA breakpoint, P is reduced by the TPA rate. for fixedwing modifies PIDFF. See **PID Attenuation and scaling** Wiki for full details."
         default_value: 0
         field: throttle.dynPID
         min: 0
-        max: 100
+        max: 200
       - name: tpa_breakpoint
         description: "See tpa_rate."
         default_value: 1500
         field: throttle.pa_breakpoint
         min: PWM_RANGE_MIN
         max: PWM_RANGE_MAX
+      - name: tpa_pitch_compensation
+        description: "Pitch angle based throttle compensation for fixed wing. Positive values will increase throttle when pitching up, and decrease throttle when pitching down."
+        default_value: 8
+        field: throttle.tpa_pitch_compensation
+        min: 0
+        max: 20
       - name: tpa_on_yaw
         description: "Throttle PID attenuation also reduces influence on YAW for multi-rotor, Should be set to ON for tilting rotors."
         type: bool
diff --git a/src/main/flight/pid.c b/src/main/flight/pid.c
index a5e34c6f795..b529b30b511 100644
--- a/src/main/flight/pid.c
+++ b/src/main/flight/pid.c
@@ -460,9 +460,6 @@ static float calculateFixedWingTPAFactor(uint16_t throttle)
         if (throttle > getThrottleIdleValue()) {
             // Calculate TPA according to throttle
             tpaFactor = 0.5f + ((float)(currentControlRateProfile->throttle.pa_breakpoint - getThrottleIdleValue()) / (throttle - getThrottleIdleValue()) / 2.0f);
-
-            // Limit to [0.5; 2] range
-            tpaFactor = constrainf(tpaFactor, 0.5f, 2.0f);
         }
         else {
             tpaFactor = 2.0f;
@@ -470,6 +467,8 @@ static float calculateFixedWingTPAFactor(uint16_t throttle)
 
         // Attenuate TPA curve according to configured amount
         tpaFactor = 1.0f + (tpaFactor - 1.0f) * (currentControlRateProfile->throttle.dynPID / 100.0f);
+        // Limit to [0.5; 2] range
+        tpaFactor = constrainf(tpaFactor, 0.3f, 2.0f);
     }
     else {
         tpaFactor = 1.0f;
@@ -488,7 +487,7 @@ static float calculateMultirotorTPAFactor(uint16_t throttle)
     } else if (throttle < getMaxThrottle()) {
         tpaFactor = (100 - (uint16_t)currentControlRateProfile->throttle.dynPID * (throttle - currentControlRateProfile->throttle.pa_breakpoint) / (float)(getMaxThrottle() - currentControlRateProfile->throttle.pa_breakpoint)) / 100.0f;
     } else {
-        tpaFactor = (100 - currentControlRateProfile->throttle.dynPID) / 100.0f;
+        tpaFactor = (100 - constrain(currentControlRateProfile->throttle.dynPID, 0, 100)) / 100.0f;
     }
 
     return tpaFactor;
@@ -502,7 +501,8 @@ static float calculateTPAThtrottle(void)
     if (usedPidControllerType == PID_TYPE_PIFF && (currentControlRateProfile->throttle.fixedWingTauMs > 0)) { //fixed wing TPA with filtering
         fpVector3_t vForward = { .v = { HeadVecEFFiltered.x, -HeadVecEFFiltered.y, -HeadVecEFFiltered.z } };
         float groundCos = vectorDotProduct(&vForward, &vDown);
-        int16_t throttleAdjustment =  currentBatteryProfile->nav.fw.pitch_to_throttle * groundCos * 90.0f; // 90 degrees is to scale from cos to throttle adjustment
+        int16_t throttleAdjustment =  currentControlRateProfile->throttle.tpa_pitch_compensation * groundCos * 90.0f / (PI/2); //when 1deg pitch up, increase throttle by pitch(deg)_to_throttle. cos(89 deg)*90/(pi/2)=0.99995,cos(80 deg)*90/(pi/2)=9.9493,
+        throttleAdjustment= throttleAdjustment<0? throttleAdjustment/2:throttleAdjustment; //reduce throttle compensation when pitch down
         uint16_t throttleAdjusted = rcCommand[THROTTLE] + constrain(throttleAdjustment, -1000, 1000);
         tpaThrottle = pt1FilterApply(&fixedWingTpaFilter, constrain(throttleAdjusted, 1000, 2000));
     }

From 4690775c8489723d1567128f562195fd015c30f8 Mon Sep 17 00:00:00 2001
From: shota hayashi <miyafly7@gmail.com>
Date: Thu, 11 Dec 2025 01:06:18 +0900
Subject: [PATCH 08/11] update docs

---
 docs/Settings.md | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/docs/Settings.md b/docs/Settings.md
index 02cae38e59b..daf6990dacb 100644
--- a/docs/Settings.md
+++ b/docs/Settings.md
@@ -6462,13 +6462,23 @@ Throttle PID attenuation also reduces influence on YAW for multi-rotor, Should b
 
 ---
 
+### tpa_pitch_compensation
+
+Pitch angle based throttle compensation for fixed wing. Positive values will increase throttle when pitching up, and decrease throttle when pitching down.
+
+| Default | Min | Max |
+| --- | --- | --- |
+| 8 | 0 | 20 |
+
+---
+
 ### tpa_rate
 
-Throttle based PID attenuation(TPA) reduces influence of PDFF on ROLL and PITCH of multi-rotor, PIDFF on ROLL,PITCH,YAW OF fixed_wing as throttle increases. For every 1% throttle after the TPA breakpoint, P is reduced by the TPA rate.
+Throttle based PID attenuation(TPA) reduces influence of PDFF on ROLL and PITCH of multi-rotor, PIDFF on ROLL,PITCH,YAW OF fixed_wing as throttle increases. On multirotor, For every 1% throttle after the TPA breakpoint, P is reduced by the TPA rate. for fixedwing modifies PIDFF. See **PID Attenuation and scaling** Wiki for full details.
 
 | Default | Min | Max |
 | --- | --- | --- |
-| 0 | 0 | 100 |
+| 0 | 0 | 200 |
 
 ---
 

From 31a5cbea8d74fd5ca8652e04b66a0fe83c9daab3 Mon Sep 17 00:00:00 2001
From: shota hayashi <miyafly7@gmail.com>
Date: Thu, 11 Dec 2025 01:10:23 +0900
Subject: [PATCH 09/11] minor fix on comments

---
 src/main/flight/pid.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/flight/pid.c b/src/main/flight/pid.c
index b529b30b511..62e3d7f0dd8 100644
--- a/src/main/flight/pid.c
+++ b/src/main/flight/pid.c
@@ -502,7 +502,7 @@ static float calculateTPAThtrottle(void)
         fpVector3_t vForward = { .v = { HeadVecEFFiltered.x, -HeadVecEFFiltered.y, -HeadVecEFFiltered.z } };
         float groundCos = vectorDotProduct(&vForward, &vDown);
         int16_t throttleAdjustment =  currentControlRateProfile->throttle.tpa_pitch_compensation * groundCos * 90.0f / (PI/2); //when 1deg pitch up, increase throttle by pitch(deg)_to_throttle. cos(89 deg)*90/(pi/2)=0.99995,cos(80 deg)*90/(pi/2)=9.9493,
-        throttleAdjustment= throttleAdjustment<0? throttleAdjustment/2:throttleAdjustment; //reduce throttle compensation when pitch down
+        throttleAdjustment= throttleAdjustment<0? throttleAdjustment/2:throttleAdjustment; //reduce throttle compensation when pitch up(when throttleAdjustment is negative which means trying to reduce "throttle")
         uint16_t throttleAdjusted = rcCommand[THROTTLE] + constrain(throttleAdjustment, -1000, 1000);
         tpaThrottle = pt1FilterApply(&fixedWingTpaFilter, constrain(throttleAdjusted, 1000, 2000));
     }

From 253cd41085fc18f9b495d0a861d1c3c4f4cb24ed Mon Sep 17 00:00:00 2001
From: shota hayashi <miyafly7@gmail.com>
Date: Thu, 11 Dec 2025 01:30:56 +0900
Subject: [PATCH 10/11] minor fix

---
 src/main/flight/pid.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/main/flight/pid.c b/src/main/flight/pid.c
index 82257897c01..b67ec110519 100644
--- a/src/main/flight/pid.c
+++ b/src/main/flight/pid.c
@@ -501,8 +501,7 @@ static float calculateTPAThtrottle(void)
     if (usedPidControllerType == PID_TYPE_PIFF && (currentControlProfile->throttle.fixedWingTauMs > 0)) { //fixed wing TPA with filtering
         fpVector3_t vForward = { .v = { HeadVecEFFiltered.x, -HeadVecEFFiltered.y, -HeadVecEFFiltered.z } };
         float groundCos = vectorDotProduct(&vForward, &vDown);
-        int16_t throttleAdjustment =  currentControlProfile->throttle.tpa_pitch_compensation * groundCos * 90.0f / (PI/2); //when 1deg pitch up, increase throttle by pitch(deg)_to_throttle. cos(89 deg)*90/(pi/2)=0.99995,cos(80 deg)*90/(pi/2)=9.9493,
-        throttleAdjustment= throttleAdjustment<0? throttleAdjustment/2:throttleAdjustment; //reduce throttle compensation when pitch up(when throttleAdjustment is negative which means trying to reduce "throttle")
+        int16_t throttleAdjustment =  currentControlProfile->throttle.tpa_pitch_compensation * groundCos * 90.0f / 1.57079632679; //when 1deg pitch up, increase throttle by pitch(deg)_to_throttle. cos(89 deg)*90/(pi/2)=0.99995,cos(80 deg)*90/(pi/2)=9.9493,
         uint16_t throttleAdjusted = rcCommand[THROTTLE] + constrain(throttleAdjustment, -1000, 1000);
         tpaThrottle = pt1FilterApply(&fixedWingTpaFilter, constrain(throttleAdjusted, 1000, 2000));
     }

From 4d3ee07ac0418cd1922c89f96ecc728777bc1e3a Mon Sep 17 00:00:00 2001
From: shota hayashi <miyafly7@gmail.com>
Date: Thu, 11 Dec 2025 01:56:32 +0900
Subject: [PATCH 11/11] fix: correct floating-point division in throttle
 adjustment calculation

---
 src/main/flight/pid.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/flight/pid.c b/src/main/flight/pid.c
index b67ec110519..7a112ff8f4f 100644
--- a/src/main/flight/pid.c
+++ b/src/main/flight/pid.c
@@ -501,7 +501,7 @@ static float calculateTPAThtrottle(void)
     if (usedPidControllerType == PID_TYPE_PIFF && (currentControlProfile->throttle.fixedWingTauMs > 0)) { //fixed wing TPA with filtering
         fpVector3_t vForward = { .v = { HeadVecEFFiltered.x, -HeadVecEFFiltered.y, -HeadVecEFFiltered.z } };
         float groundCos = vectorDotProduct(&vForward, &vDown);
-        int16_t throttleAdjustment =  currentControlProfile->throttle.tpa_pitch_compensation * groundCos * 90.0f / 1.57079632679; //when 1deg pitch up, increase throttle by pitch(deg)_to_throttle. cos(89 deg)*90/(pi/2)=0.99995,cos(80 deg)*90/(pi/2)=9.9493,
+        int16_t throttleAdjustment =  currentControlProfile->throttle.tpa_pitch_compensation * groundCos * 90.0f / 1.57079632679f; //when 1deg pitch up, increase throttle by pitch(deg)_to_throttle. cos(89 deg)*90/(pi/2)=0.99995,cos(80 deg)*90/(pi/2)=9.9493,
         uint16_t throttleAdjusted = rcCommand[THROTTLE] + constrain(throttleAdjustment, -1000, 1000);
         tpaThrottle = pt1FilterApply(&fixedWingTpaFilter, constrain(throttleAdjusted, 1000, 2000));
     }