atco-matic - further to excrab's explanation about cruising levels on the DHC8 fleet, a rough guide is to use the sector distance as the cruising level of choice, up to the aircraft's ceiling (without drop-down oxy masks) of FL250, i.e. 180nm = FL180 cruise, and so on.
Additionally, a little info to any ATCers out there, the DHC8-400 is as flexible in the climb and descent as you want it to be, whatever the load. Just ask and thou shalt receive.
