I haven't played my copy of Freespace/Silent Threat in years (although I've been back in the Descent 3 community for a while now), and recently started re-playing the main FS1 campaign.
Near the beginning of the mission "The Hammer and the Anvil", a weakened ship appears in the far distance, asking to be rescued. The mission script seems to be designed so the ship is destoyed soon thereafter, while the player sticks to his/her assigned escort duty (or if the player decides to attempt a rescue, they're too far away).
However, if at the beginning of the level, the player takes off for the area where this ship will appear, it's possible to reach it before it gets destroyed. But every time I've tried this, the ship is destroyed anyway, despite everything I try.
I seem to remember being able to keep the ship from being destroyed once, many years ago (probably playing on "Easy" at the time)... but it doesn't seem to be possible on the harder difficulties I'm playing on now.
Is it possible, and if so, what's the best way to do it? Also, is there any reward for this at the end of the mission?