Simple enough. Sit in a Phalanx... enemy pops a anti-infantry mine next to you. Kills you while you are inside the turret. :/
Are you sure it's killing you inside the turret? One of my new favorite things to do is place a AP mine where you get in/out of the turret then hack the turret forcing them out directly onto my mine insta-killing them. That may be what happened to you.
what Obe said is true, ive done it a few times as well. you can tell what kinda mine it is by the image at the "X Killed X" tag up in the top right corner, if its got yellow striping its an AVM, should also tell you in the "you where killed by" death screen. it might be proximity or it might be the mine blowing UP the turret.
Probably a bug, I have dropped 3 AT mines on a turret before, an did nothing to him, jsut made the turret smoke a little.
I wonder what genius dev decided to make mines invisible, fire and forget and insta kill, must be from the COD school of development
they have to be mate or els they become utterly useless. Engi dont have any real ability to control the battlefield, our AT/AP mines are all we have. besides that anyone with flak armor becomes instantly immune to mines.