Hi Barrick,
Good luck with testing today...

The short answer is:
Channel 4 = Collective
Channel 2 = Aileron
Channel 1 = Pitch (or elevator)

To find out for yourself in the future or for other aircraft:
Click on the Edit Transmitter and look at the second column (blue color and it's called Channel name)
Click on the description in any cell and in the header it identifies the Channel number.

Best of luck
Scott