Any night vision equipment will pick up the beam. In the military, we would wear the cav-navs, and have battles with remote control units and laser pens.
There are many ways to make a LASER these days.
The most common is to get a read/write disk player from a computer. It is very easy to disassemble, solder 2 wires to what is there, and place this in a 6v maglight. Very common with Blu-Ray players to make a blue laser pointer...
The local high school kids, as a project, took a full size laser printer apart, the unit inside ran at 5W...so figure out what power that had compared to a laser pen...
There are many laser range finding devices out there as well, from gun sights to binoculars and survey equipment.
One thing, nothing you can do about stupid.
Perhaps a reflective film on the aircraft windows to prevent the beam from getting inside.