Life Flight of Maine is an IFR program. IFR stands for Instrument Flight Rules (versus VFR, Visual Flight Rules). IFR means you can fly in the clouds with zero visibility. You use only your instruments to guide you (instead of looking outside). So, instead of looking out the window and seeing that you are X number of feet in the air and that X mountain is off to your left or X building to your right, you rely on technology alone to get you where you need to go.
In order to do this, you have to be flying the right helicopter (not all helis have the stuff you need to fly IFR), and you need to have nerves of steel.
Here’s a video of Stéphane getting a little IFR practice flight in. The flight nurses tag along (in case they get a call while they are out flying) and one of them took a little footage of the trip.