Left Switch Panel
The left panel includes five categories of switches, the two magneto step switches and the gear lever. These are grouped in different colours:
- Electrical switches in blue
- Icing switches in yellow
- Light switches in grey
- Fuel switches in green
- Fan switches in orange
Most of them are straight forward, but with some of them I had my problems. These are the icing switches, because the virtual FSX cockpit shows a lot more icing switches, than I have implemented here. The reason for this is very simple: I did not manage to find the associated FSX events and variables, because in the virtual cockpit most of the switches a coupled. An example are the two pitot switches in the virtual cockpit, having one for the left and one for the right side. Looking to the Simconnect variables, you only find the entry 'PITOT HEAT', but nothing for the left or right side, which is shown in the right pictures with the left hand numbering:
- This shows all switches in the OFF position
- When switching one of the pitot switches, both switches are set to ON
- When switching the 'Surface Auto' switch, all remaining switches are set to ON
- Only the 'Propeller' switch can be set to ON as a single switch
This has totally confused me and I did also not find the associated FSX events for setting the switches individually. I therefore decided to implement the most important ones, which are the ones in the above picture, having one heat switch for both pitots, the left and right engine heat switches, followed by the propeller and structural heating switches. I will inform you in time, when I am flying in the future in cold weather and crash the aircraft.
I've added some cockpit light switches that I think are useful, because that's exactly what I have in my car, which is just a mid-range car.
As already mentioned, it is the intention to close the cockpit by a cabin. Therefore there is the need for fresh air, which shall come out of the three air vents in the mid lower panel. Behind the air vents there is a ventilator, which can be switched ON by the 'FAN' switch. In addition the speed of the ventilator can be increased by switching the 'FAN LEVEL' switch to ON. But whether I can ever make the other two switches functional remains my secret (AC and HEAT).
Because the levers of the small standard switches are not long enough and of course not coloured, they were extended by small brass pipes. One of the open side was closed with glue (Patex Stabilit), then sanded and sprayed with the required paint and finally glued onto the short switch lever arm. It's clear that the control of these switches do not require any FSX event, they only need some cabling within the cockpit.
The two magneto step switches have five positions, i.e. OFF, RIGHT, LEFT, BOTH and START. In the BOTH position, both magneto ignition distributors are in the ON state. This is the absolutely necessary redundancy scheme, if in flight one ignition distributor system fails. Having switched ON the engines and before taxing, it has to be checked, that both systems are working. This can be tested by turning the step switch to the RIGHT and LEFT position. If at both positions the engine does not stop, then both ignition distributor systems are working correctly.
These two magneto step switches require a dedicated design, because in the START position they have to jump back to the BOTH position, like the ignition switch in my old car. This is realised by two 3D printed PLA lever arms, which are mounted on the centre axis of the step switches. To force them to jump back, a lateral axis made out of aluminium with two stop-rings and a spring were designed. This works perfect and I was not required to buy some used very very expensive ones from a real cockpit. The two knobs were 3D printed and sprayed with silver paint.
The landing gear lever was made out of several 3D printed PLA parts, finally glued together. The housing also consist of some PLA parts, rigid white FOREX foam plates and a small snap switch. The lever was sprayed with black and white paint. The lever can only be moved up or down, when completely pulled out. To ensure the correct final position, the lever is fixated by an additional spring.
The plate for mounting all the switches, the LEDs, the gear lever mechanism and the magneto step switches is made out of 3 mm black hard PVC. The design is shown below before having performed the cabling of all the elements.
To control the switches and the LEDs a dedicated controller board was designed, which is based on an ATmega32 micro-processor. The schematics is shown below, is nearly self explaining and holds no mysteries. All inputs ports are activated by their internal pull-up resistors.