LU17,
Is it to go on the EAL training course by any chance?
You can fly MAN-BOH via Dublin with Ryan Air. You're going out of you way a bit but it still works out quicker than the train. I checked it out on the Ryanair web site and the flight were reasonable too, one of the sectors was only 1 euro each way!
Don't know if prices have gone up but have a look.