In one Cure mission, I outran a borg torp, engaged evasion action and there was 2 kilometres left. I ran over to Kang and was about to engage the BOPS on the other side when all of a sudden, the torp hit me. No I wasn't close to the other cube.
I know it was the borg torp because it did 15k damage to my hull and took out my fully charged rear shields. (the nearest rear target was 30 kilometres away)
Whatever, it didn't cost me the optional but I got killed as with that much hull damage, I was slaughtered by the other bops.
Anyways, again, I see a borg plasma torp and I shoot it down at 2 kilometres. A few seconds later, my ship registered a hit from a borg plasma torp. More specifically, the one I had shot down seconds earlier. I watched it dissipate and nothing happened for 2 seconds. No there was no follow up shot as sometimes the cube does fire a salvo.
I've seen this before: It seems anytime a torpedo times out without having reached its target, it will auto-hit its target. Therefore, it is impossible to outrun torpedoes: If you try, you'll just delay it until it times out, then automatically get hit even if the torpedo is nowhere near you. This is probably one of the causes of invisible Borg torpedoes, as it is fairly easy to outrun the thing by accident and have no idea it was ever there as a result.
It's not a MMOSIM. Whether or not a torp hits you is determined when it's fired.
So when you were within 10km of the Cube and it fired a Torp at you? At that time, it rolled some dice and determined that the torp hit you. After that, the only thing that can prevent it from hitting you is if... well actually I can't think of one. Even if you die... I've seen the torp still hit .
This works both ways too, I can fire Heavy Torps from 1km and not get 'feedback' by quickly turning around the moment the first torp leaves the launcher. I don't have to keep the target within the 90' arc until all torps are launched. The game determines if I get to shoot my trio of torps, but it doesn't determine it individually, only if my first torp is 'good' or 'not'. I can therefore fire my first torp, turn around and run, even as the other torps are launched. I've seen my last torp leave my ship even when I'm 10km+ away from the target AND pointing away from it. (using EM/APO/Deutherium)