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superconnie
09-26-2007, 03:41 PM
I hope this has not been answered before.... if so, then sorry, it's my first day ;)

I'm building a Super Constellation cockpit and I don't know how to solve my propeller reverser problem. Since I'm using original aircraft parts, I'm a bit restricted in the possibilities. The problem is the following:

The reverser levers are mechanically coupled with the throttle levers. If I pull them up, a small switch is activated and the throttles open up to maximum 30%.
Originally the switch was used to tell the propeller control box to set the prop pitch to reverse. The engines RPM were then increased and that slowed down the aircraft. In fact, it was possible to taxi backwards that way but you had to be very careful with the brakes because you could make the plane fall down on it's tail.

Now I have to tell the Simulator that I want to have a negative pitch by pushing that little switch and then it shall interpret the throttle movement as reverse thrust and slow down the plane.

How can I do that?

I know that it will not work the way I just described... I have already figured out a possible solution together witch a friend but I'd like to have a more elegant way to solve that.
Currently I have this solution. I add a resistor to the throttle potentiometer. This has the effect that the lowest position of the pot is not zero but (for example) 30%. If I pull then the reversers, the switch will short circuit the resistor and that gives the 0% throttle value. This is then interpreted by the software as reverse thrust.

It's a bit complicated to describe but I hope you know what I mean.:cool:

Thanks in advance
Christian

Trevor Hale
09-26-2007, 03:53 PM
I hope this has not been answered before.... if so, then sorry, it's my first day ;)

I'm building a Super Constellation cockpit and I don't know how to solve my propeller reverser problem. Since I'm using original aircraft parts, I'm a bit restricted in the possibilities. The problem is the following:

The reverser levers are mechanically coupled with the throttle levers. If I pull them up, a small switch is activated and the throttles open up to maximum 30%.
Originally the switch was used to tell the propeller control box to set the prop pitch to reverse. The engines RPM were then increased and that slowed down the aircraft. In fact, it was possible to taxi backwards that way but you had to be very careful with the brakes because you could make the plane fall down on it's tail.

Now I have to tell the Simulator that I want to have a negative pitch by pushing that little switch and then it shall interpret the throttle movement as reverse thrust and slow down the plane.

How can I do that?

I know that it will not work the way I just described... I have already figured out a possible solution together witch a friend but I'd like to have a more elegant way to solve that.
Currently I have this solution. I add a resistor to the throttle potentiometer. This has the effect that the lowest position of the pot is not zero but (for example) 30%. If I pull then the reversers, the switch will short circuit the resistor and that gives the 0% throttle value. This is then interpreted by the software as reverse thrust.

It's a bit complicated to describe but I hope you know what I mean.:cool:

Thanks in advance
Christian

Dude... It can be even easier then that.. Check it out. Attach that "Switch" to your interface and program it for a key press of the F2 Key (repeating) through FSUIPC. When that switch is locked in the "reverse position" the engines go into reverse mode full boar. When you disengage and return the throttle to idle, this will disengage that switch you speak of, and Program the off position for FSUIPC F1 key press.

Am I totally misunderstanding what you describe or is this going to work for ya?

Best regards,

Trev

Trevor Hale
09-26-2007, 03:56 PM
Oh forgot to add, you will need to have that switch probably connected through a relay cause it will need to disengage your "throttle" pots while in reverse mode otherwise the sim won't be able to decide if you want rev thrust or forward thrust.

But easy as pie either way!

Trev

superconnie
09-26-2007, 04:09 PM
Well that sounds much easier than my idea.... Of course thats it! I forgot that I can program a activate and release function in FSUIPC... thanks alot! I will try that :D

superconnie
09-27-2007, 02:00 PM
There is still a little problem. I use the TRC-Simkits Multicontroller for all kind of lamps, switches and servos. To assign a function to the 23 I/O ports, there is a software called MC-calibration and this software uses a list of functions with the corresponding numbers from FSUIPC and also Project Magenta. But I have not seen any F-keys to assign.... I know that I can assign the F2 function to my joystick buttons in the flight simulator. But the Multicontroller is not seen as a joystick.

Does someone have experience with simkits? Or do I have to cannibalize my joystick to get that F2 assigned to my switch?

Second question: I have 4 switches, one for each engine... is it possible to reverse each engine independently? Or is there only a "global reverse" for all together?

Trevor Hale
09-27-2007, 02:20 PM
You can specify the engine. F2 does all engines, you will have to specify the engine via Offset possibly.

For instance, My reverser on my Dassault is only on engine #2 so I have that key assigned in FSUIPC to reverse engine #2 only.

Trev

superconnie
11-16-2007, 05:24 PM
The propeller reverser problem is solved. I made a little interface for the interface and thanks to the good ideas of you all, it really works! Please have a look in the photo gallery to see what I did the whole week long... :-)

Christian