The Engineer is a support/defence class, constructing and repairing vehicles, deployables, and objectives (such as bridges and machinery). He also deploys and maintains defence turrets, such as the Anti-Personnel, Anti-Missile and Anti-Vehicle deployables. The Engineer carries the N80 Assault Rifle or N22 Shotgun and multi-purpose mines.
It takes approximately 16 seconds per stage of construction.
Defusing planted explosives takes ~6 seconds; if an engineer is defusing planted explosives, you will see a red progress bar overlaid on the dyno timer bar.
Once a deployment spot is selected, it will take ~34 seconds before a turret is deployed and operational.
You can drop a mine (unarmed) then toss a Frag Grenade on it to get some additional bang - very useful for taking out turrets or a vehicle that is isn't moving.