Dang it. Didn't have that on my hulls cheat sheet and must have missed it when you first commented on it. I'll have to go and rethink that design a bit, as I don't think a spare engine makes sense on a ship that small. Might stick (MNE) or a couple H on it. With 2 H, the EXs could explore without CFN maintenance for a very, very long time. Or maybe Ya....
Also thanks to Cenalt for pointing out the same thing (plus strategic movement problems) in the turn 1 thread.