Are window frames structural?

Question

My circa 1920 house is one story, solid brick from the footings in the basement to the roof. Three layer thick up to the first floor joists, then two layers to the roof. The basement windows are all look like this (through the three layer portion of the wall). Basically a hole through the wall lined with 2x8s:

There does not appear to be any sort of lintel, apart from the three arched courses of brick.

I want to install more functional windows. The question then is: Can I remove all the wooden parts, window and frame, or is the frame contribute to the wall structure? I would leave the wooden arch (arrow) used to square off the opening. It makes a big difference in the dimensions of the windows I would order...

Answer 1

An arch (if engineered correctly) is self supporting. No need for a lintel at all.

From the looks of it, that arch is more than adequate to hold the brick above so I'd say that wooden piece is merely a filler--not a structural element.