Two Pipe Chess

This game is an entry in the contest to create a 41-square chess variant.  The name is based on the initial arrangement of pieces, which looks somewhat like two tobacco pipes. (Also, the board can be seen as two pipes surrounding a three-rank, five-file center rectangle.)
 

Board Setup

The board has nine files and five ranks, with squares a5, b5, h1 and i1 removed,  and has this initial setup: