The superluminal drive is a 'warp' drive, in that the device generates a warp bubble which itself then moves at faster than light velocity.
A successful warp jump requires calculations which may take anywhere from days to months to complete on 22nd century supercomputer systems. The time required varies depending on the distance between the departure and destination points and on both points' depth inside gravity wells.
Generating, maintaining and controlling a warp bubble takes relatively little energy.
The end result of the calculations is a 'flight plan' which describes the trajectory, velocity, and so on of any warp bubble travelling between the departure and destination point. This is also time-dependent, i.e. the flight plan is only accurate for one point in time, which is therefore always set to be some time after the completion of the calculations (if the calculations unexpectedly take longer and are not finished when this point in time ticks by, they will need to be aborted and started again). There is a small window during which the ship's onboard computers can correct for errors induced by performing the jump at the incorrect time.
It is possible to correct for such errors because once a flight plan exists for one point in time, it is much easier and faster to calculate a new flight plan for another point in time shortly afterwards assuming the same departure and destination points.
If the ship cannot correct for this error, the warp bubble's shape and trajectory will be distorted. If the ship is fortunate, i.e. if the distortion is minimal, it will arrive at a destination specified by this new erroneous flight path. If it is unfortunate, the distortion of the warp bubble will be great enough to bring its interior wall in contact with the ship. Contact with the interior wall of a warp bubble results in the immediate conversion of matter into energy.
If this error is great enough to make the flight plan essentially invalid (in practical terms, this might mean outside of said several second-wide window), this may have several effects. The ship may appear to enter warp normally, followed by immediately disappearing without a trace; it may enter warp normally, after which the bubble will collapse; it may fail to enter warp, but generate a huge amount of energy (released as heat and x-rays) which would otherwise have gone into creating a warp bubble; or nothing at all may happen.
If the shipboard systems responsible for controlling the warp bubble are rendered inoperative while in flight, the bubble becomes 'free-flying' and entirely unpredictable.
Warp bubbles simply pass through all matter while in flight, although they do constantly radiate energy and it is possible to see out from within.
A flight plan typically has 'drop-out' points built-in as a safety precaution at regular intervals along its trajectory; should an emergency occur, the ship can dissolve the warp bubble and drop out of warp near any of these points.
It is possible to detect warp bubbles from outside, this growing progressively more difficult the greater the distance to the warp bubble. It also depends on the warp bubble's velocity relative to the observer, i.e. a warp bubble moving away from them at sufficient velocity may be impossible or very difficult to detect.
It is furthermore possible to induce the aforementioned distortions artificially; this is generally done to force a ship to drop out of warp. While it can be used to destroy an enemy ship outright, this practice may be prohibited by international convention. This effect can only be achieved from relatively close range (and can also be employed by one ship inside a warp bubble to target another vessel in warp), though 'close range' depends on how deep one is inside a gravity well.
If a system calculating a flight plan is able to communicate with another system at the destination point, the length of time taken to perform said calculations is dramatically reduced. This results in the establishment of 'FTL stations' acting as jump-points. This frees spacecraft of needing to calculate their own flight plan. Such stations continually run these calculations. Ships desiring to make the jump to the station at the 'other end' simply park near the station and wait; when a new flight plan is finished, the station transmits it to all of them. At this point, they all enter warp simultaneously, following the flight plan.