Gents,

For who is interested something to read in the dark days that come.

The airspeed sensor is ready, only encapsulation I have still to do.
I will do that later after the calibration with the pitot tube with my car.

Important for me was to make the sensor and so to know the dimensions and give it a place in the wing.
Now I can make a compartment beside the aileron servo, in the centre section of the wing, see the picture.

The service plug to measure the signal for zero adjustment and this adjusting I make in the bottom of the wing centre section so I can check the signal without removing the wings.
Two tubes from about 22 cm / 9 “ will connect the pitot tube near the left side main wheel leg with the sensor.

Some values of the instrument I show in the sheet of picture 1, for me to archive together with the circuit diagram.

Picture 2 the 3D layout of compressed components in the instrument. All before I will fill the space between the components with suet/tallow?. (Yes I also flying 3D)
Picture 3 Weight 39 grams, (1 ¼ ounce?)

Picture 4 the place in the wing.

ABOUT MEASUREMENT

For cruise control I do mount the transmitter normal directly near the pitot tube.
The speed of measurement has to be as fast as possible to adjust a high control loop gain and have the best cruise control.
For the Wester Taurus the connection tubes to the pitot tube will be around 25 cm (9”) so the measurement is a little slower but still within tenths of seconds.
I will not use cruise control in the Wester Taurus in the first flight period.

SOME FACTS ABOUT CRUISE CONTROL

For cruise control I use a root extractor that calculates the pressure difference of the pitot tube to values speed, see the diagram, 10 km/h (10 % speed) the pressure difference is only 1 % of the max value, 4 % difference for 20 km/h etc.. See picture 5.

In the diagram it is also interesting to see the engine is used for 50 % of his action as a brake when the speed is above the setpoint. The – part of the “line of action”
This works because the cruise control keeps the RPM’s of the engine on controlled values so the propeller doesn’t stall. Only near Idle and above 80 – 90 km/h I think the break doesn’t work or bad , the angles of attack of the prop are too negative.

I Hope to learn more of this possibility of airbrake in the second part of flying with the Wester Taurus and the algorithm, parameters but also propeller to use.

Braking power of the engine will depend on the profile of the propeller and is like inverted flying with an asymmetrical wing! Also the shape of the nose radius is important because of the negative angles of attack. The weight of the plane decides the braking force and the pressure difference over the area of the rotating propeller together with the total drag of the plane.

Normally, with my TF Taurus, I fly with higher gain values than showed in the diagram and not alone with proportional action but also with differential and integrating but these are not easy to explain. The Wester Taurus will be a lot lighter so the cruise control must do better on this plane especially the brake action..

With a measured airspeed beneath the setpoint it is thrust what we get from the engine, see diagram the + of the “line of action”.

Limitation of the setpoint above the stall speed is my security to fly with low speeds without stalling.
In the diagram the setpoint is 70 km/h as example.
The engine Idle is adjusted to prevent the engine is cut off by the controller.

So enough about the electronics, you have something to read and I now making dust again.

Cees