// @Description: Level of aggressiveness of pitch and roll PID gains. Lower values result in a 'softer' tune. Level 6 recommended for most planes. A value of 0 means to keep the current values of RMAX and TCONST for the controllers, tuning only the PID values
// @Description: Degrees of down pitch added when throttle is below TRIM_THROTTLE in FBWA and AUTOTUNE modes. Scales linearly so full value is added when THR_MIN is reached. Helps to keep airspeed higher in glides or landing approaches and prevents accidental stalls. 2 degrees recommended for most planes.
// @Description: This controls the minimum altitude change for a waypoint before a glide slope will be used instead of an immediate altitude change. The default value is 15 meters, which helps to smooth out waypoint missions where small altitude changes happen near waypoints. If you don't want glide slopes to be used in missions then you can set this to zero, which will disable glide slope calculations. Otherwise you can set it to a minimum number of meters of altitude error to the destination waypoint before a glide slope will be used to change altitude.
// @Description: This controls the height above the glide slope the plane may be before rebuilding a glide slope. This is useful for smoothing out an autotakeoff
// @Description: When enabled, this adds user stick input to the control surfaces in auto modes, allowing the user to have some degree of flight control without changing modes. There are two types of stick mixing available. If you set STICK_MIXING to 1 then it will use "fly by wire" mixing, which controls the roll and pitch in the same way that the FBWA mode does. This is the safest option if you usually fly ArduPlane in FBWA or FBWB mode. If you set STICK_MIXING to 2 then it will enable direct mixing mode, which is what the STABILIZE mode uses. That will allow for much more extreme maneuvers while in AUTO mode. If you set STICK_MIXING to 3 then it will apply to the yaw while in quadplane modes only, such as while doing an automatic VTOL takeoff or landing.
// @Values: 0:Disabled,1:FBWMixing,2:DirectMixing,3:VTOL Yaw only
// @Description: When enabled this option gives FBWA navigation and steering in AUTO mode. This can be used to allow manual stabilised piloting with waypoint logic for triggering payloads. With this enabled the pilot has the same control over the plane as in FBWA mode, and the normal AUTO navigation is completely disabled. THIS OPTION IS NOT RECOMMENDED FOR NORMAL USE.
// @Description: Minimum GPS ground speed in m/s used by the speed check that un-suppresses throttle in auto-takeoff. This can be be used for catapult launches where you want the motor to engage only after the plane leaves the catapult, but it is preferable to use the TKOFF_THR_MINACC and TKOFF_THR_DELAY parameters for catapult launches due to the errors associated with GPS measurements. For hand launches with a pusher prop it is strongly advised that this parameter be set to a value no less than 4 m/s to provide additional protection against premature motor start. Note that the GPS velocity will lag the real velocity by about 0.5 seconds. The ground speed check is delayed by the TKOFF_THR_DELAY parameter.
// @Description: Minimum forward acceleration in m/s/s before arming the ground speed check in auto-takeoff. This is meant to be used for hand launches. Setting this value to 0 disables the acceleration test which means the ground speed check will always be armed which could allow GPS velocity jumps to start the engine. For hand launches and bungee launches this should be set to around 15. Also see TKOFF_ACCEL_CNT paramter for control of full "shake to arm".
// @Description: This parameter sets the time delay (in 1/10ths of a second) that the ground speed check is delayed after the forward acceleration check controlled by TKOFF_THR_MINACC has passed. For hand launches with pusher propellers it is essential that this is set to a value of no less than 2 (0.2 seconds) to ensure that the aircraft is safely clear of the throwers arm before the motor can start. For bungee launches a larger value can be used (such as 30) to give time for the bungee to release from the aircraft before the motor is started.
// @Description: This parameter sets the amount of elevator to apply during the initial stage of a takeoff. It is used to hold the tail wheel of a taildragger on the ground during the initial takeoff stage to give maximum steering. This option should be combined with the TKOFF_TDRAG_SPD1 option and the GROUND_STEER_ALT option along with tuning of the ground steering controller. A value of zero means to bypass the initial "tail hold" stage of takeoff. Set to zero for hand and catapult launch. For tail-draggers you should normally set this to 100, meaning full up elevator during the initial stage of takeoff. For most tricycle undercarriage aircraft a value of zero will work well, but for some tricycle aircraft a small negative value (say around -20 to -30) will apply down elevator which will hold the nose wheel firmly on the ground during initial acceleration. Only use a negative value if you find that the nosewheel doesn't grip well during takeoff. Too much down elevator on a tricycle undercarriage may cause instability in steering as the plane pivots around the nosewheel. Add down elevator 10 percent at a time.
// @Description: This parameter sets the airspeed at which to stop holding the tail down and transition to rudder control of steering on the ground. When TKOFF_TDRAG_SPD1 is reached the pitch of the aircraft will be held level until TKOFF_ROTATE_SPD is reached, at which point the takeoff pitch specified in the mission will be used to "rotate" the pitch for takeoff climb. Set TKOFF_TDRAG_SPD1 to zero to go straight to rotation. This should be set to zero for hand launch and catapult launch. It should also be set to zero for tricycle undercarriages unless you are using the method above to genetly hold the nose wheel down. For tail dragger aircraft it should be set just below the stall speed.
// @Description: This parameter sets the airspeed at which the aircraft will "rotate", setting climb pitch specified in the mission. If TKOFF_ROTATE_SPD is zero then the climb pitch will be used as soon as takeoff is started. For hand launch and catapult launches a TKOFF_ROTATE_SPD of zero should be set. For all ground launches TKOFF_ROTATE_SPD should be set above the stall speed, usually by about 10 to 30 percent
// @Description: This parameter sets the slew rate for the throttle during auto takeoff. When this is zero the THR_SLEWRATE parameter is used during takeoff. For rolling takeoffs it can be a good idea to set a lower slewrate for takeoff to give a slower acceleration which can improve ground steering control. The value is a percentage throttle change per second, so a value of 20 means to advance the throttle over 5 seconds on takeoff. Values below 20 are not recommended as they may cause the plane to try to climb out with too little throttle. A value of -1 means no limit on slew rate in takeoff.
// @Description: This parameter reduces the pitch minimum limit of an auto-takeoff just a few seconds before it reaches the target altitude. This reduces overshoot by allowing the flight controller to start leveling off a few seconds before reaching the target height. When set to zero, the mission pitch min is enforced all the way to and through the target altitude, otherwise the pitch min slowly reduces to zero in the final segment. This is the pitch_min, not the demand. The flight controller should still be commanding to gain altitude to finish the takeoff but with this param it is not forcing it higher than it wants to be.
// @Description: This controls the maximum bank angle in degrees during flight modes where level flight is desired, such as in the final stages of landing, and during auto takeoff. This should be a small angle (such as 5 degrees) to prevent a wing hitting the runway during takeoff or landing. Setting this to zero will completely disable heading hold on auto takeoff and final landing approach.
// @Description: This controls when to use reverse thrust. If set to zero then reverse thrust is never used. If set to a non-zero value then the bits correspond to flight stages where reverse thrust may be used. Note that reverse thrust is only ever auto-enabled in auto-throttle modes. In modes where throttle control is pilot controlled the ability to do reverse thrust is controlled by throttle stick input. The most commonly used value for USE_REV_THRUST is 2, which means AUTO_LAND only. That enables reverse thrust in the landing stage of AUTO mode. Another common choice is 1, which means to use reverse thrust in all auto flight stages.
// @Description: Which navigation controller to enable. Currently the only navigation controller available is L1. From time to time other experimental controllers will be added which are selected using this parameter.
// @Description: This sets what algorithm will be used for altitude control. The default is zero, which selects the most appropriate algorithm for your airframe. Currently the default is to use TECS (total energy control system). From time to time we will add other experimental altitude control algorithms which will be selected using this parameter.
// @Description: Defines the maximum distance from a waypoint that when crossed indicates the waypoint may be complete. To avoid the aircraft looping around the waypoint in case it misses by more than the WP_RADIUS an additional check is made to see if the aircraft has crossed a "finish line" passing through the waypoint and perpendicular to the flight path from the previous waypoint. If that finish line is crossed then the waypoint is considered complete. Note that the navigation controller may decide to turn later than WP_RADIUS before a waypoint, based on how sharp the turn is and the speed of the aircraft. It is safe to set WP_RADIUS much larger than the usual turn radius of your aircraft and the navigation controller will work out when to turn. If you set WP_RADIUS too small then you will tend to overshoot the turns.
// @Description: Sets the maximum distance to a waypoint for the waypoint to be considered complete. This overrides the "cross the finish line" logic that is normally used to consider a waypoint complete. For normal AUTO behaviour this parameter should be set to zero. Using a non-zero value is only recommended when it is critical that the aircraft does approach within the given radius, and should loop around until it has done so. This can cause the aircraft to loop forever if its turn radius is greater than the maximum radius set.
// @Description: Defines the distance from the waypoint center, the plane will maintain during a loiter. If you set this value to a negative number then the default loiter direction will be counter-clockwise instead of clockwise.
// @Description: Defines the radius of the loiter circle when in RTL mode. If this is zero then WP_LOITER_RAD is used. If the radius is negative then a counter-clockwise is used. If positive then a clockwise loiter is used.
// @Description: Enables roll limits at low airspeed in roll limiting flight modes. Roll limits based on aerodynamic load factor in turns and scale on ARSPD_FBW_MIN that must be set correctly. Without airspeed sensor, uses synthetic airspeed from wind speed estimate that may both be inaccurate.
// @Description: Maximum airspeed demanded in automatic throttle modes. Should be set slightly less than level flight speed at THR_MAX and also at least 50% above ARSPD_FBW_MIN to allow for accurate TECS altitude control.
// @Description: Reverse sense of elevator in FBWB and CRUISE modes. When set to 0 up elevator (pulling back on the stick) means to lower altitude. When set to 1, up elevator means to raise altitude.
// @Description: This enables terrain following for CRUISE mode, FBWB mode, RTL and for rally points. To use this option you also need to set TERRAIN_ENABLE to 1, which enables terrain data fetching from the GCS, and you need to have a GCS that supports sending terrain data to the aircraft. When terrain following is enabled then CRUISE and FBWB mode will hold height above terrain rather than height above home. In RTL the return to launch altitude will be considered to be a height above the terrain. Rally point altitudes will be taken as height above the terrain. This option does not affect mission items, which have a per-waypoint flag for whether they are height above home or height above the terrain. To use terrain following missions you need a ground station which can set the waypoint type to be a terrain height waypoint when creating the mission.
// @Description: This controls how far ahead the terrain following code looks to ensure it stays above upcoming terrain. A value of zero means no lookahead, so the controller will track only the terrain directly below the aircraft. The lookahead will never extend beyond the next waypoint when in AUTO mode.
// @Description: This sets the rate in m/s at which FBWB and CRUISE modes will change its target altitude for full elevator deflection. Note that the actual climb rate of the aircraft can be lower than this, depending on your airspeed and throttle control settings. If you have this parameter set to the default value of 2.0, then holding the elevator at maximum deflection for 10 seconds would change the target altitude by 20 meters.
// @Description: Minimum throttle percentage used in all modes except manual, provided THR_PASS_STAB is not set. Negative values allow reverse thrust if hardware supports it.
// @Description: Maximum change in throttle percentage per second. Lower limit based on 1 microsend of servo increase per loop. Divide SCHED_LOOP_RATE by approximately 10 to determine minimum achievable value.
// @Description: maximum percentage change in flap output per second. A setting of 25 means to not change the flap by more than 25% of the full flap range in one second. A value of 0 means no rate limiting.
// @Description: When throttle is suppressed in auto mode it is normally forced to zero. If you enable this option, then while suppressed it will be manual throttle. This is useful on petrol engines to hold the idle throttle manually while waiting for takeoff
// @Description: If this is set then when in STABILIZE, FBWA or ACRO modes the throttle is a direct passthru from the transmitter. This means the THR_MIN and THR_MAX settings are not used in these modes. This is useful for petrol engines where you setup a throttle cut switch that suppresses the throttle below the normal minimum.
// @Description: 0 disables the failsafe. 1 enables failsafe on loss of RC input. This is detected either by throttle values below THR_FS_VALUE, loss of receiver valid pulses/data, or by the FS bit in receivers that provide it, like SBUS. A programmable failsafe action will occur and RC inputs, if present, will be ignored. A value of 2 means that the RC inputs won't be used when RC failsafe is detected by any of the above methods, but it won't trigger an RC failsafe action.
// @Description: The PWM level on the throttle input channel below which throttle failsafe triggers. Note that this should be well below the normal minimum for your throttle channel.
// @Description: Target percentage of throttle to apply for flight in automatic throttle modes and throttle percentage that maintains TRIM_ARSPD_CM. Caution: low battery voltages at the end of flights may require higher throttle to maintain airspeed.
// @Description: When enabled, this uses the throttle input in auto-throttle modes to 'nudge' the throttle or airspeed to higher or lower values. When you have an airspeed sensor the nudge affects the target airspeed, so that throttle inputs above 50% will increase the target airspeed from TRIM_ARSPD_CM up to a maximum of ARSPD_FBW_MAX. When no airspeed sensor is enabled the throttle nudge will push up the target throttle for throttle inputs above 50%.
// @Description: The action to take on a short (FS_SHORT_TIMEOUT) failsafe event. A short failsafe event can be triggered either by loss of RC control (see THR_FS_VALUE) or by loss of GCS control (see FS_GCS_ENABL). If in CIRCLE or RTL mode this parameter is ignored. A short failsafe event in stabilization and manual modes will cause a change to CIRCLE mode if FS_SHORT_ACTN is 0 or 1, and a change to FBWA mode if FS_SHORT_ACTN is 2. In all other modes (AUTO, GUIDED and LOITER) a short failsafe event will cause no mode change if FS_SHORT_ACTN is set to 0, will cause a change to CIRCLE mode if set to 1 and will change to FBWA mode if set to 2. Please see the documentation for FS_LONG_ACTN for the behaviour after FS_LONG_TIMEOUT seconds of failsafe.
// @Description: The action to take on a long (FS_LONG_TIMEOUT seconds) failsafe event. If the aircraft was in a stabilization or manual mode when failsafe started and a long failsafe occurs then it will change to RTL mode if FS_LONG_ACTN is 0 or 1, and will change to FBWA if FS_LONG_ACTN is set to 2. If the aircraft was in an auto mode (such as AUTO or GUIDED) when the failsafe started then it will continue in the auto mode if FS_LONG_ACTN is set to 0, will change to RTL mode if FS_LONG_ACTN is set to 1 and will change to FBWA mode if FS_LONG_ACTN is set to 2. If FS_LONG_ACTION is set to 3, the parachute will be deployed (make sure the chute is configured and enabled).
// @Description: Enable ground control station telemetry failsafe. Failsafe will trigger after FS_LONG_TIMEOUT seconds of no MAVLink heartbeat messages. There are three possible enabled settings. Setting FS_GCS_ENABL to 1 means that GCS failsafe will be triggered when the aircraft has not received a MAVLink HEARTBEAT message. Setting FS_GCS_ENABL to 2 means that GCS failsafe will be triggered on either a loss of HEARTBEAT messages, or a RADIO_STATUS message from a MAVLink enabled 3DR radio indicating that the ground station is not receiving status updates from the aircraft, which is indicated by the RADIO_STATUS.remrssi field being zero (this may happen if you have a one way link due to asymmetric noise on the ground station and aircraft radios).Setting FS_GCS_ENABL to 3 means that GCS failsafe will be triggered by Heartbeat(like option one), but only in AUTO mode. WARNING: Enabling this option opens up the possibility of your plane going into failsafe mode and running the motor on the ground it it loses contact with your ground station. If this option is enabled on an electric plane then you should enable ARMING_REQUIRED.
// @Description: Maximum bank angle commanded in modes with stabilized limits. Increase this value for sharper turns, but decrease to prevent accelerated stalls.
// @Description: Altitude at which to use the ground steering controller on the rudder. If non-zero then the STEER2SRV controller will be used to control the rudder for altitudes within this limit of the home altitude.
// @Description: Enables the setting SERVOn_TRIM values to current levels when switching out of MANUAL mode. Should not be left on as mode switches while the plane is rolling or pitching can cause invalid trim values and subsequent unstable behavior. See newer and safer SERVO_AUTO_TRIM parameter for automated results.
// @Description: The gain for the Vtail and elevon output mixers. The default is 0.5, which ensures that the mixer doesn't saturate, allowing both input channels to go to extremes while retaining control over the output. Hardware mixers often have a 1.0 gain, which gives more servo throw, but can saturate. If you don't have enough throw on your servos with VTAIL_OUTPUT or ELEVON_OUTPUT enabled then you can raise the gain using MIXING_GAIN. The mixer allows outputs in the range 900 to 2100 microseconds.
// @Description: Enable rudder only mode. The rudder will control attitude in attitude controlled modes (such as FBWA). You should setup your transmitter to send roll stick inputs to the RCMAP_YAW channel (normally channel 4). The rudder servo should be attached to the RCMAP_YAW channel as well. Note that automatic ground steering will be disabled for rudder only aircraft. You should also set KFF_RDDRMIX to 1.0. You will also need to setup the YAW2SRV_DAMP yaw damping appropriately for your aircraft. A value of 0.5 for YAW2SRV_DAMP is a good starting point.
// @Description: The offset for the Vtail and elevon output mixers, as a percentage. This can be used in combination with MIXING_GAIN to configure how the control surfaces respond to input. The response to aileron or elevator input can be increased by setting this parameter to a positive or negative value. A common usage is to enter a positive value to increase the aileron response of the elevons of a flying wing. The default value of zero will leave the aileron-input response equal to the elevator-input response.
// @Description: Sets the amount of deflection that the rudder output will apply to the differential spoilers, as a percentage. The default value of 100 results in full rudder applying full deflection. A value of 0 will result in the differential spoilers exactly following the elevons (no rudder effect).
// @Description: Bitmap of what on-board log types to enable. This value is made up of the sum of each of the log types you want to be saved. It is usually best just to enable all log types by setting this to 65535. The individual bits are ATTITUDE_FAST=1, ATTITUDE_MEDIUM=2, GPS=4, PerformanceMonitoring=8, ControlTuning=16, NavigationTuning=32, Mode=64, IMU=128, Commands=256, Battery=512, Compass=1024, TECS=2048, Camera=4096, RCandServo=8192, Sonar=16384, Arming=32768, FullLogs=65535
// @Description: Target altitude above home for RTL mode. Maintains current altitude if set to -1. Rally point altitudes are used if plane does not return to home.
// @Description: This is the minimum altitude in centimeters that FBWB and CRUISE modes will allow. If you attempt to descend below this altitude then the plane will level off. A value of zero means no limit.
// @Description: The speed in meters per second at which to engage FLAP_1_PERCENT of flaps. Note that FLAP_1_SPEED should be greater than or equal to FLAP_2_SPEED
// @Description: The speed in meters per second at which to engage FLAP_2_PERCENT of flaps. Note that FLAP_1_SPEED should be greater than or equal to FLAP_2_SPEED
// @Description: If set to a non-zero value then this is an RC input channel number to use for giving IO manual control in case the main FMU microcontroller on a board with a IO co-processor fails. When this RC input channel goes above 1750 the FMU microcontroller will no longer be involved in controlling the servos and instead the IO microcontroller will directly control the servos. Note that IO manual control will be automatically activated if the FMU crashes for any reason. This parameter allows you to test for correct manual behaviour without actually crashing the FMU. This parameter is can be set to a non-zero value either for ground testing purposes or for giving the effect of an external override control board. Please also see the docs on OVERRIDE_SAFETY. Note that you may set OVERRIDE_CHAN to the same channel as FLTMODE_CH to get IO based override when in flight mode 6. Note that when override is triggered due to a FMU crash the 6 auxiliary output channels on Pixhawk will no longer be updated, so all the flight controls you need must be assigned to the first 8 channels.
// @Description: This controls whether the safety switch is turned off when you activate override with OVERRIDE_CHAN. When set to 1 the safety switch is de-activated (activating the servos) then a IO override is triggered. In that case the safety remains de-activated after override is disabled. If OVERRIDE_SAFETTY is set to 0 then the safety switch state does not change. Note that regardless of the value of this parameter the servos will be active while override is active.
// @Description: This enables and disables hardware in the loop mode. If HIL_MODE is 1 then on the next reboot all sensors are replaced with HIL sensors which come from the GCS.
// @Description: This controls whether real servo controls are used in HIL mode. If you enable this then the APM will control the real servos in HIL mode. If disabled it will report servo values, but will not output to the real servos. Be careful that your motor and propeller are not connected if you enable this option.
// @DisplayName: Limit of error in HIL attitude before reset
// @Description: This controls the maximum error in degrees on any axis before HIL will reset the DCM attitude to match the HIL_STATE attitude. This limit will prevent poor timing on HIL from causing a major attitude error. If the value is zero then no limit applies.
// @Description: Automatically begin landing sequence after arriving at RTL location. This requires the addition of a DO_LAND_START mission item, which acts as a marker for the start of a landing sequence. The closest landing sequence will be chosen to the current location.
// @Description: X-Axis deceleration threshold to notify the crash detector that there was a possible impact which helps disarm the motor quickly after a crash. This value should be much higher than normal negative x-axis forces during normal flight, check flight log files to determine the average IMU.x values for your aircraft and motor type. Higher value means less sensative (triggers on higher impact). For electric planes that don't vibrate much during fight a value of 25 is good (that's about 2.5G). For petrol/nitro planes you'll want a higher value. Set to 0 to disable the collision detector.
// @Description: Automatically detect a crash during AUTO flight and perform the bitmask selected action(s). Disarm will turn off motor for safety and to help against burning out ESC and motor. Set to 0 to disable crash detection.
// @Description: This enables the use of a rangefinder for automatic landing. The rangefinder will be used both on the landing approach and for final flare
// @Description: Mask of R/C channels to pass directly to corresponding output channel when in MANUAL mode. When in any mode except MANUAL the channels selected with this option behave normally. This parameter is designed to allow for complex mixing strategies to be used for MANUAL flight using transmitter based mixing. Note that when this option is used you need to be very careful with pre-flight checks to ensure that the output is correct both in MANUAL and non-MANUAL modes.
// @Description: When the aircraft is within this altitude of the home waypoint, while disarmed it will automatically update the home position. Set to 0 to continously reset it.
// @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, 3:Force target airspeed to trim airspeed in Cruise or FBWB, 4: Climb to ALT_HOLD_RTL before turning for RTL, 5: Enable yaw damper in acro mode, 6: Surpress speed scaling during auto takeoffs to be 1 or less to prevent oscillations without airpseed sensor.
// @Description: This is the number of acceleration events to require for arming with TKOFF_THR_MINACC. The default is 1, which means a single forward acceleration above TKOFF_THR_MINACC will arm. By setting this higher than 1 you can require more forward/backward movements to arm.
// @Description: This is amount of deflection applied to the two outer surfaces for differential spoilers for flaps to give crow flaps. It is a number from 0 to 100. At zero no crow flaps are applied. A recommended starting value is 25.
// @Description: This is amount of deflection applied to the two inner surfaces for differential spoilers for flaps to give crow flaps. It is a number from 0 to 100. At zero no crow flaps are applied. A recommended starting value is 45.
// @Description: This is the timeout for an automatic takeoff. If this is non-zero and the aircraft does not reach a ground speed of at least 4 m/s within this number of seconds then the takeoff is aborted and the vehicle disarmed. If the value is zero then no timeout applies.
// @Values: 0: none, 1: D spoilers have pitch input, 2: use both control surfaces on each wing for roll, 4: Progressive crow flaps only first (0-50% flap in) then crow flaps (50 - 100% flap in)
// @Description: This scales down the inner flaps so less than full downwards range can be used for differential spoiler and full span ailerons, 100 is use full range, upwards travel is unaffected
// @Description: Forward throttle battery voltage compensation maximum voltage (voltage above this will have no additional scaling effect on thrust). Recommend 4.2 * cell count, 0 = Disabled. Recommend THR_MAX is set to no more than 100 x FWD_BAT_VOLT_MIN / FWD_BAT_VOLT_MAX, THR_MIN is set to no less than -100 x FWD_BAT_VOLT_MIN / FWD_BAT_VOLT_MAX and climb descent rate limits are set accordingly.
// @Description: Forward throttle battery voltage compensation minimum voltage (voltage below this will have no additional scaling effect on thrust). Recommend 3.5 * cell count, 0 = Disabled. Recommend THR_MAX is set to no more than 100 x FWD_BAT_VOLT_MIN / FWD_BAT_VOLT_MAX, THR_MIN is set to no less than -100 x FWD_BAT_VOLT_MIN / FWD_BAT_VOLT_MAX and climb descent rate limits are set accordingly.
// @Description: The vehicle will climb this many m during the initial climb portion of the RTL. During this time the roll will be limited to LEVEL_ROLL_LIMIT degrees.