In their primary defensive application, the ship's phaser arrays land single or multiple beams upon a target in an attempt to damage the target structure, sometimes to complete destruction. As with other Starfleet-developed hardware, the Type IX phaser is highly adaptable to a variety of situations, from active low-energy scans to high-velocity ship to-ship combat operations.
The exact performance of most phaser firings is determined by an extensive set of practical and theoretical scenarios stored within the main computers. Artificial intelligence routines shape the power levels and discharge behaviors of the phaser arrays automatically, once specific commands are given by responsible officers to act against designated targets.
Low-energy operations provide a valuable direct method of transferring ship's energy for a variety of controlled applications, such as active sensor scanning. In high-energy weapon firings, several interrelated computer systems work to place the beam on the target, all within a few milliseconds.
Long and short-range sensor scans provide target information to the Threat assessment/tracking/targeting system (TA/T/TS), which drives the phaser arrays with the best target coverage. Multiple targets are prioritized and acted upon in order. The maximum effective tactical range of ship's phasers is 300,000 kilometers.
Targets protected by defensive EM shields and surface absorptive-ablative coatings may still be dealt with, but with a commensurate increase in power to defeat the shields. Phasers may be fired one-way through the ship's own shields due to EM polarization, with a small acceptable drag force penalty at the inner shield interface.
Threat vessels will be encountered with a wide variety of shields that act upon phaser emissions to reduce their effectiveness; the type most often confronted spreads the beam cross section, redirecting the energy around the shields and back into space. Higher power levels will usually overburden the shields and allow the phaser to hit the target directly, although more sophisticated adversaries possess highly resistant shield generators.
It has been the experience of some starship tactical officers that rapid-firing volleys at different parts of a shield bubble can weaken it. The phaser arrays on a Nova class ship are located to achieve maximum beam dwell time on a target. Generally speaking, regardless of the actual beam type, pulse or continuous, or the specific Threat situation, the most effective tactic is to maintain contact between the beam and the Threat shield or physical hull.
Computer sequencing of the arrays will always attempt to expose the target, even while the arrays are recharging. Conversely, the best tactics for minimizing disabling return phaser fire are to present the smallest visible ship cross section to the Threat weapons, and continue changing attitude so as to deny the beams any sites on which to inflict concentrated energies.
In Cruise Mode, all phaser arrays receive their primary power from the warp reaction chamber, with supplementary fusion power from the impulse engine systems. Recharge times are kept to <0.5 seconds. Full power firing endurance is rated at =45 minutes. Survival during crises depends on the understanding by Tactical officers of the constraints of both modes.
The actual number of variables involved in spacecraft defense can be staggering and would quickly overwhelm any manual efforts to adequately protect a starship. While shipto- ship operations may seem as simple as pointing and shooting, computers and semiautonomous weapon systems are the accepted standards, driven by the realities of the spaceflight regime.
In the total Starfleet history of armed spacecraft, over 3,500 unique spacecraft combat maneuvers (SCMs) have been recorded, too numerous to present more than a tiny fraction in detail (see descriptions following). Since combat conditions can change within seconds, high-speed calculations and tactical choices will also change rapidly.
General result-oriented firing and movement orders from command personnel are translated by the main computers and scripted into "trees" of possible sequences, along with a prioritization of the best paths for the current time, and influenced by the predictions of Threat assessment routines. As with the navigation system, which is directly linked to the tactical system within the main computers, phaser algorithms take two distinct forms, baseline code and self-rewritable code.
Both code types cover all known advantages and weaknesses of Threat vessels, including simulated adversaries used for training purposes, and analysis routines for new Threat types. The rewritable symbolic code performs primarily high-speed autonomic functions related to the defense of the Solstice, quickly reacting to danger from outside and repairing internal damage.
Only 10% of the rewritable code is needed for weapon fire control routines; they are fairly straightforward and are complicated only by firing sequences, precise timings, and unusual targeting requirements. All stored rewritable code is routinely transferred to Starfleet Headquarters and remote sites by secure means for high-level analysis.