Newton Airlines

Sunday, 1 February 2026

INAV configuration for Spektrum Radios

I don't have any Spektrum gear to check this but INAV setup is the same as any other radio system apart from channel order and Serial Receiver Provider.

Spektrum radios use TAER channel order and Serial Receiver Provider is SRXL2 (or SBUS if available). Make these selections in the INAV Receiver page.

SRXL2 signal wire connects to the T pin of your selected Serial Receiver UART.

Configure the INAV Model Mix in the radio with 100% for the first 4 channels (TAER), and the Arming and Mode switches. This may be the Multirotor premix in Spektrum radios.

In the INAV Receiver page, check that the channel graph bars move to the right when you move the sticks up and right.

If all this is working but Arming is still not possible check this Troubleshooting checklist

Monday, 25 August 2025

Crow braking

EdgeTX mix for a glider with Flaps and Crow Braking on the S1 slider

I like to shorten flap pushrods so the flaps go from Level with wing to Full down using full servo movement.

Start with a basic mix.

Note: "IAil" is the Input named "Ail" from the Inputs Page.

Ch1 100 IAil - Aileron L
Ch2 100 IEle - Elevator
Ch3 100 IThr - Throttle
Ch4 100 IRud - Rudder
Ch5 100 IAil - Aileron R
Ch6 100 S1 - Flap L
Ch7 100 S1 - Flap R

Check control surface movements and change weight to -100 if throw direction is reversed
Reduce rates from 100 if desired, but it's better to move the pushrods to an inner servo arm hole to reduce throws.

Now add mixer lines to Ch1 and Ch5
Source S1, Weight 30 (or -30 if required), Curve Func x>0, Multiplex Add (+=)

Mixer lines should now look like this

Ch1 100 IAil

+= 30 S1 x>0

Ch5 100 IAil

+= -30 S1 x>0

Change the weight from 30 to -30 to reverse the movement if required. Ailerons should move up as flaps go down. 30% weight is just a suggestion, adjust as required.

Func x>0 means the Ailerons will only move UP for the bottom half of S1 rotation. Otherwise Offset will be required to re-level the ailerons when the flaps are up.

If Elevator compensation is required to prevent pitching up when flaps are dropped

Add mixer line to Ch2 .

Source S1, Weight 5 (or -5 if required), Curve Func x>0, Multiplex Add (+=)

Ch2 100 IEle

+= 5 S1 x>0

Make sure the elevator moves down with S1. Fly and test whether weight of 5 is suitable. Adjust as required.

If Expo is required, add it in the INPUTS page

Curve Expo 30

If Differential is required, add it in the Mixer page for each Aileron channel

Curve Diff 50 (or -50 as required)

Sunday, 17 August 2025

INAV Troubleshooting - Quick Tips

1. FIRMWARE

Are you using the correct firmware target for your board?

Note that the SpeedyBee F405 Wing Mini board uses the WING target, NOT the MINI target.

2. BOARD ORIENTATION

Does the animation move the same way as your plane?

Set FC orientation using the Alignment Tool if the board is not facing forward

3. INAV MIX in the RADIO

Do Not set up V-Tail or Elevon mixing in the radio, that is done in the INAV Mixer

Must use this basic mix in the radio. I call it the INAV Mix.

Ch1 100 AIL
Ch2 100 ELE
Ch3 100 THR
Ch4 100 RUD
Ch5 ARM Switch (must be Ch5 for ELRS)

Ch6 7 8 etc. for your desired flight modes, but always include a switch position where no modes are selected. This will allow for ACRO.

In the radio, adjust the endpoints of Ch 1 to 4 to give PWM range of 1000 to 2000 in the INAV Receiver graphs.

4. OUPUTS Page - Enable Motor and Servo Output

Choose the correct ESC Protocol and Servo Refresh Rate for your gear.

Use STANDARD and 50 Hz if they are unknown.

Use the slider controls on this page to calibrate Standard ESCs, and check if the motor runs.

5. PORTS - Enable separate UARTs for Serial RX, GPS and Digital FPV if required.

SBUS Rx with F405 boards require Serial RX to be on UART2.

6. CONFIGURATION - Turn On "GPS for Navigation and Telemetry" (if GPS will be used)

7. FAILSAFE - Only set as RTH if you have a GPS setup.

Arming will be prevented if failsafe is RTH on a non-GPS setup.

8. RECEIVER - Connect the receiver to the Serial RX UART
Choose the Channel Order for your type of radio. AETR is most common
Choose the Serial Receiver Provider for your receiver - CRSF for ELRS, SBUS for SBUS etc.

Check that the Rx is bound to your radio.

Check that the INAV Channel bars for Roll, Pitch, Yaw and Throttle move to the RIGHT when moving the radio sticks UP and RIGHT?

If one moves to the left then you may have reversed a channel in the radio.

9. ARMING PROBLEMS - Read the Arming Flags message along the bottom of the INAV window and in your FPV goggles. Type STATUS in to the CLI for more clues.

Arming is only possible in ACRO, HORIZON, ANGLE or MANUAL modes, and GPS must have acquired at least 6 satellites and a 3D lock.

To bypass the Arming Flags, hold the throttle stick down and yaw right while arming.

BEWARE this is for troubleshooting only and is not a safe flying condition.

Disconnect the battery to clear Arming Flag bypass.