Plane: added FLIGHT_OPTIONS bit for disabling pitch up check in takeoff

some takeoff procedures use high pitch angles

ArduPlane/Parameters.cpp

@@ -1173,7 +1173,7 @@ const AP_Param::GroupInfo ParametersG2::var_info[] = {
     // @Param: FLIGHT_OPTIONS
     // @DisplayName: Flight mode options
     // @Description: Flight mode specific options
-    // @Bitmask: 0:Rudder mixing in direct flight modes only (Manual Stabilize Acro),1:Use centered throttle in Cruise or FBWB to indicate trim airspeed
+    // @Bitmask: 0:Rudder mixing in direct flight modes only (Manual, Stabilize, Acro),1:Use centered throttle in Cruise or FBWB to indicate trim airspeed, 2:Disable attitude check for takeoff arming
     // @User: Advanced
     AP_GROUPINFO("FLIGHT_OPTIONS", 13, ParametersG2, flight_options, 0),
 

ArduPlane/defines.h

@@ -201,4 +201,5 @@ enum {
 enum FlightOptions {
     DIRECT_RUDDER_ONLY   = (1 << 0),
     CRUISE_TRIM_THROTTLE = (1 << 1),
+    DISABLE_TOFF_ATTITUDE_CHK = (1 << 2),
 };

ArduPlane/takeoff.cpp

@@ -75,10 +75,10 @@ bool Plane::auto_takeoff_check(void)
         goto no_launch;
     }
 
-    if (!quadplane.is_tailsitter()) {
+    if (!quadplane.is_tailsitter() &&
+        !(g2.flight_options & FlightOptions::DISABLE_TOFF_ATTITUDE_CHK)) {
         // Check aircraft attitude for bad launch
-        if (ahrs.pitch_sensor <= -3000 ||
-            ahrs.pitch_sensor >= 4500 ||
+        if (ahrs.pitch_sensor <= -3000 || ahrs.pitch_sensor >= 4500 ||
             (!fly_inverted() && labs(ahrs.roll_sensor) > 3000)) {
             gcs().send_text(MAV_SEVERITY_WARNING, "Bad launch AUTO");
             takeoff_state.accel_event_counter = 0;