How can I set up local comms so I (in the same room) can speak to someone flying with headphones on using a separate mic?

[Tree_Beard]

To clarify-

I use a Delan Clip head tracker while flying and its attached to my Sennheiser HD280 headphones. Works great.

One annoying characteristic of this setup, though, is that obviously you can't hear anyone talking to you with the headphones on. Occasionally friends will come over and want to fly with my setup, which is great, but the problem is I can't tell them how to operate the jet without pausing the sim or turning the game volume down extremely low, which is lame. 

Ideally what I'd like to be able to do is talk into a mic and the audio comes through in game through the pilots headphones, just like how a real instructor would speak to you if you were taking flying lessons.

Is this possible and, if so, what hardware do I need? I already have headphones (obviously) and a variety of USB mics, so I'm hoping I can rig something up without buying anything new but I'm open to all options. 

Let me know, thanks. 

 

[The_Nephilim]

well if you have a laptop or a secondary PC you can set up a local Teamspeak3 server and client and use that. the only other way would be with a 2 way radio or CB.

[Ala12Rv-Tundra]

Most simple solution would be having dcs audio via regular speakers. 

Secondly, if you are willing to keep dcs audio via headphones, you can connect your mic, and mess with windows recording and playback options to force that mic input to be put through the headphones the other guy is using. 

Another option would be using a software called Voicemeeter banana which is used to mix audio channels, but never used it sorry

[AegisFX]

I was coming to say the same thing tundra was saying. Use another microphone and make it so Windows will play it back. I think it's called "monitoring"

[HiJack]

I believe you want the VB Audio Cable. 
https://vb-audio.com/Cable/

Virtual audio cable letting you have several input source devices.