Mig-31 has air refuel boom, but cannot find action shortcut key

[uboats]

Just look at the mig31 3d model, you can find the air refuel boom.

Then I created an AI map, and mig31 is able to do air refueling.

http://www.digitalcombatsimulator.com/en/files/487456/

 

So, I made a flyable mig31 mod with su33 fc2 cockpit and key binding.

However, all shortcut keys worked except

1. folding wing (mig31 model cannot, so useless)

2. tail (mig31 model does not have it)

3. airbrake (no animation action, but the light works and has script effect)

 

4. air refuel boom (nothing happened)

In the cockpit view, there is no response after press lctrl+r,

In F2 view, there is none either.

 

I looked at all the keyboard input lua files for those planes who have air refuel capability.

And I found all of them are using the same script command.

Then I manually copy .the refueling boom command to mig31 keyboard file, which can be found in the option->control->mig-31. However, during flying mig31, the command did nothing.

 

Could anyone can help me to find out howto make mig31 be able to do air refueling?

[SkateZilla]

Moved to Mods Section as this isnt a BUG.