Table mounted landing gear selector switch from a Tornado

Cheers guys

So here's a fun little thing I put together

I don't have room for a full pit in which to integrate a "full" landing gear handle setup, so I have been struggling to find a satisfying solution beyond toggle switches with 3d printed levers stuck on them.

What I did was I bought a Tornado gear switch assembly on EBay (as others around here have) and converted it for use with DCS and mounted it to the side of a Monstertech joystick table mount.

It is fun to operate and makes landings and takeoffs that much more involved when you have to throw that heavy handle :joystick:

The box fits pretty snugly on the side of the alu profile and doesn't get in the way of joystick or leg/rudder movements in neither up or down handle positions.

I have it sitting high enough off of the mounting plate so it is easy to grab and operate without getting any fingers pinched.

To be more realistic it should probably sit off to the left side of the throttle of course but I found it interfered with the throttle when I tried mounting it there.

In practice I find it very easy and fast to find and operate the gear lever without having to look down.

To hold the box in place I tried plastic strips and clamps at first which didn't really work. I then tried clamping it using standard corner brackets from Monstertech and it turns out that they fit just perfectly! They're cheap and easy to install.

I'm thinking to buy another gear switch and convert it to a hook handle that I can place on the right side of the joystick for added fun around the carrier.

The switch assembly has the wiring schematic printed on the side and the pins on the back are labeled so wiring it up was very straightforward.

I didn't have a mil connector and I didn't want to pry the thing open so I soldered directly onto the pins in the back. A crappy but functional solution.

I have it hooked up to a Nano running DCS BIOS and it works perfectly with both the F/A-18C and the A-10C. I'm sure it would work with the other modules but I haven't tested it.

There were little bulbs in the gear handle but I couldn't get them to light up so I swapped them out for a pair of ultra bright red LEDs. I drive them with 5V PWM straight from the Nano with no issue. They look white in the video but they actually shine a nice red.

The assembly has a mechanical downlock that is disabled by either manually pressing the override button or by activating the solenoid inside. It is rated at 28V but 12V from a regular (switching) wall adapter works just fine.

I control power supply for the solenoid with a little MOSFET circuit that engages when DCS BIOS outputs an airspeed higher than taxi speed, since we can't seem to check for weight-on-wheels directly. More precisely I read the airspeed gauge postion and just engage the 12v when it is above 10% of max or whatever.

/*
 Tell DCS-BIOS to use a serial connection and use the default Arduino Serial
 library. This will work on the vast majority of Arduino-compatible boards,
 but you can get corrupted data if you have too many or too slow outputs
 (e.g. when you have multiple character displays), because the receive
 buffer can fill up if the sketch spends too much time updating them.
 
 If you can, use the IRQ Serial connection instead.
*/
#define DCSBIOS_DEFAULT_SERIAL

#include "DcsBios.h"

int GearUpAllowed = 0;
int GearUpSpeed = 650;

/* paste code snippets from the reference documentation here */


const byte gearLeverPins[2] = {8, 7};
DcsBios::SwitchMultiPos gearLever("GEAR_LEVER", gearLeverPins, 2);

void onStbyAsiAirspeedChange(unsigned int newValue) {
   if (newValue > GearUpSpeed){
     GearUpAllowed = 1;
   }
   else {
     GearUpAllowed = 0;
   }
}
DcsBios::IntegerBuffer stbyAsiAirspeedBuffer(0x54d8, 0xffff, 0, onStbyAsiAirspeedChange);

void onGearLeverLightChange(unsigned int newValue) {
  if (newValue == 1){
   analogWrite(6, 255);
  }
  else {
   analogWrite(6, 0);
  }
}
DcsBios::IntegerBuffer gearLeverLightBuffer(0x5470, 0x0800, 11, onGearLeverLightChange);

void setup() {
 DcsBios::setup();
 pinMode(9, OUTPUT);
}

void loop() {
 DcsBios::loop();
 if (GearUpAllowed == 1){ 
   digitalWrite(9, HIGH); //activate solenoid
 }
 if (GearUpAllowed == 0){
   digitalWrite(9, LOW); 
 }
}

Here's crappy video showing the switch in action. You can hear a clank as the jet accelerates and the solenoid energizes and disables the downlock.

Here's link to the Monstertech corner brackets - needs the fastening set option to attach to the profile.

That's great work!

Good idea on the airspeed to operate the solonoid.

I've got one of those Tornado levers lying around as well, after seeing yours I think I'll get it out and wire it up!

Sent from my SM-G950F using Tapatalk

Agreed. Nice job and very good idea with the airspeed to release the solenoid. Just directed Fusedspine33 to this idea. Keep up the work sir.

Cheers

Solo

That's great work!

 

Good idea on the airspeed to operate the solonoid.

 

I've got one of those Tornado levers lying around as well, after seeing yours I think I'll get it out and wire it up!

 

Sent from my SM-G950F using Tapatalk

Just lying around!! They dont seem to have any of that in Aus.

Edit: https://www.ebay.com.au/itm/PANAVIA-TORNADO-AIRCRAFT-COCKPIT-LANDING-GEAR-LEVER/232916936614?hash=item363aee67a6:g:DO0AAOSwy6la8PEf

And as if by magic..........

Thanks for the comments guys. The setup is still working great after a few weeks of use.

I bought another gear switch from this guy to convert into a hook switch:

https://www.ebay.com/itm/RAF-Aircraft-Undercarriage-Selector-Switch-as-fitted-to-Tornado-Aircraft/223124835190

He only has one more left if anyone's interested, but then there's many similar switches to be found, e.g. https://www.ebay.com/itm/Aircraft-ZE158-1986-Panavia-Tornado-F-3-Undercarriage-U-C-Selector-Switch-K0653/223155655591 This model seems to be quite common. It is a little different from the one I have and I can't make out if the two little holes on the end is supposed to light up during operation.

can i ask u to share ur instruction on how u did this with the nano and its wiring . but thats if u dont mind, i dont wanna step on ur toes . ty in advance,

btw, thats is a freakin kick ass video nd how u set this up. thats an awesome video. great job

can i ask u to share ur instruction on how u did this with the nano and its wiring . but thats if u dont mind, i dont wanna step on ur toes . ty in advance,

The gear switch assembly is basically just a mechanism that throws a bunch of toggle switches when you move the handle up or down. I've put LEDs in the handle that light up in place of the little lamps there were there originally and they're wired through the handle and out the back along with the toggle switches.

So...the wiring is very straightforward and follows exactly how you would wire any toggle switch and any LED to any Arduino board.

I strongly recommend that you follow Ian's tutorial to learn how to do exactly that and how to use the DCS BIOS code as well:

http://dcs-bios.a10c.de/docs/v0.7.0/userguide.html

It shows an example for an Uno and the A-10C module but the principle works for any board and any module, including the Nano and the F/A-18C.

If you want to learn about how to control a solenoid I recommend that you check out Hansolo's thread or GSS Rain's excellent videos, like

DeadMeat, did you measure the current draw of the solenoid by any chance? Working on a PCB to drive one of these (but waiting for all the bits to arrive in the post), and want to make sure I'm designing with appropriate FETs and so forth.

DeadMeat, did you measure the current draw of the solenoid by any chance? Working on a PCB to drive one of these (but waiting for all the bits to arrive in the post), and want to make sure I'm designing with appropriate FETs and so forth.

I just measured 0.3A @12VDC or 0.65A @28VDC.

Cheers

Hans

I just measured 0.3A @12VDC or 0.65A @28VDC.

 

Cheers

Hans

DeadMeat, did you measure the current draw of the solenoid by any chance? Working on a PCB to drive one of these (but waiting for all the bits to arrive in the post), and want to make sure I'm designing with appropriate FETs and so forth.

Yeah, I measure the same 0,3A @12V.

For the FET, I think most logic level MOSFET would be okay, since these are designed to give you full output at 5V. I use IRL540NPBF to drive these gear switches as well as my mag switches.

Got the hook switch up and running.

It is a pretty simple conversion of another Tornado gear switch bought on EBay with a few added details. The handle dimensions are interpreted from photos and adjusted to fit the switch so I'm sure they're not accurate.

The wheel handle is replaced with a custom designed, 3D printed hook handle.

The red handle lights have been swapped for a bright green LED to provide backlight for the 'HOOK' lettering and there is a notch for holding a metal bar to defeat the uplock mechanism.

The handle is printed in semi transparent material and painted so the letters can be illuminated from within.

The painting process is like I do knobs and light plates - first a thin white base layer (Tamiya Primer L spray), then the letters are masked off with delicate 1 mm modeller's masking tape, followed by two layers of gray paint (Tamiya AS-7 spray). Finally the masking tape is removed and two layers of clear matte varnish is applied. Each layer is allowed to dry before the next is applied.

The letters are probably sunk in a bit too deep as it was pretty difficult to mask the round shapes off and get the white paint in there in an even fashion.

I had to cover some light leaks as well so the final paint job looks a little rough up close I guess. We'll call this a draft version :)

The backlight intensity is PWM controlled and coded to follow the INST PNL knob position and I've coded a check to see if conditions should allow it to turn on.

It seems we need power on the AC bus, which we can check for indirectly by looking at least one generator switch on and the corresponding engine RPM on the IFEI at least in ground IDLE (let's say above 60%).

I've skipped the check for ground power, so during maintenance the plane cap will have to feel her way around the pit in darkness I'm afraid.

The LED wiring is routed through the handle and out the back using the existing wiring. I just installed a 150R resistor back there.

I've installed a hook indicator light in the front plate. This is the top part of a NKK KB series rectangular illuminated push button with the dinky amber LED. I drilled out the hole in the front plate to 8,5mm to fit the indicator and the wiring (including a 150R resistor) is simply routed out the back over the solenoid. The 'HOOK' label is simply printed on a clear sheet, cut to size and fitted behind the cap.

The downlock solenoid is fed a constant supply of 12V from the landing gear switch source to keep it disengaged. I went ahead and wrapped wire around the back of the override button to keep it pressed in as well so I guess I'm covered here. The uplock is defeated by keeping a sawn off 16 mm part of the lever mechanism wedged down and in place by a slot in the handle.

I use the same Monstertech brackets for mounting as I did for the landing gear switch in the first post.

Here's a short video of the switch, the backlight and the indicator in action:

Very nice work DeadMeat :thumbup:

Cheers

Hans

Love it!

Sent from my SM-G950F using Tapatalk

I bought another gear switch from this guy to convert into a hook switch:

https://www.ebay.com/itm/RAF-Aircraft-Undercarriage-Selector-Switch-as-fitted-to-Tornado-Aircraft/223124835190

 

He only has one more left if anyone's interested.

Not anymore he doesn't. :)

Don't think I'll manage anything quite as impressive as your working solenoid but an LED should be within my limits. Having said that, I wouldn't see it from inside the Vive.

Thanks guys. It certainly adds to the fun around the carrier.

Brun, if you don't want to mess with the solenoid, the easiest way to disable downlock mechanically is probably to just unscrew the front panel and wrap something around the red override button behind to keep it pressed in when you screw the panel back on.

Ah, so it's locked by default and requires power to override that? For some reason I assumed it was the other way round.

Thanks for the hint, it sounds pretty simple to overcome.

Can you share the 3d print model for the hook as I've got a Tornado gear lever ready and waiting for just this task!

Can you share the 3d print model for the hook as I've got a Tornado gear lever ready and waiting for just this task!

Sure - I have uploaded the file to the Autodesk gallery. You have to register to download it I think.

I haven't refined the file further than my initial version.

I printed in Shapeways' smooth fine detail plastic material for the translucency and detail but if you don't want to bother with backlight you can print in a cheaper material of course. The tolerances are pretty tight as it is so I'm not sure how the fit will be if you print in another material or use another printer.

Sure - I have uploaded the file to the Autodesk gallery. You have to register to download it I think.

I haven't refined the file further than my initial version.

 

I printed in Shapeways' smooth fine detail plastic material for the translucency and detail but if you don't want to bother with backlight you can print in a cheaper material of course. The tolerances are pretty tight as it is so I'm not sure how the fit will be if you print in another material or use another printer.

Cheers buddy! Just got one ordered up so look forward to getting that :thumbup:

Where you get the gearspeed = 650 from? is that 65 knots?

Where you get the gearspeed = 650 from? is that 65 knots?

Check your DCS BIOS documentation, select advanced. 65535 is the max deflection of the gauge, meaning 650 is about 10%. You can translate this to a specific indicated airspeed. The idea is that if your airspeed is above stall speed, then you should be off the ground without WoW :smartass:

If you're on a moving carrier and you're taxing forward in that frame of reference your indicated airspeed can get pretty high even though you still have WoW, let's say 25 knots + your taxi speed = pretty fast indicated. In practice you may want to use a bigger value than 650, I think I indeed did adjust it up a bit.

A bit of background - from what I can tell we can only infer if we have WoW in DCS BIOS, there is no specific variable that can be read directly. Alternatives to reading the airspeed gauge position (sensitive to stall speed, icing of probes, movement of carrier), could be the barometric altitude gauge (sensitive to pressure setting) and the radar altitude gauge in the F18.

I suppose if you really want to be specific and make the WoW inference airframe independent, you could calculate an absolute velocity from changes to the DCS BIOS commonData lat and long coordinates. You may want to throw MSL altitude change in there to account for vertical component (climbing) and get the true vector and velocity :huh:

Regardless of how you do it, you will face the issue that stall speed varies with aircraft weight, air density, load factor and lift coefficient - variables that we can't read directly from DCS BIOS..

Check your DCS BIOS documentation, select advanced. 65535 is the max deflection of the gauge, meaning 650 is about 10%.

Ah yes, that make sense. Thanks.

In my case I just went with the state of the landing gear down and locked light. For what I am doing using landing gear state is good enough.

Small correction to my statement - 650 is more like 1% of full deflection :) So we may want to use a bigger value if we're going for stall speed approximation..

Ah yes, that make sense. Thanks.

 

In my case I just went with the state of the landing gear down and locked light. For what I am doing using landing gear state is good enough.

Gear down lights is a good indicator that you're on the ground or close to it. Depending on what you want to use it for it can be okay

That looks great, but it's missing the tape they used to put around it to stop it falling apart...which it used to do a lot...LOL