ST weapon accuracy and range
This article deals with demonstrated accuracy and range of various weapons used by major Star Trek civilizations like the Federation, Borg, Dominion, and Klingon Empire.
As the examples provided below demonstrate, all major military forces engage at ranges from several hundred meters up to several kilometers, which represents the upper limit of their demonstrated effective range.
Examples
DS9 "The Die is Cast"
Commander Sisko orders Dax to bring the Defiant to within 500 meters of a group of Jem'Hadar fighters before firing on them. The advantage he sought by closing to such short range isn't clear. However the Jem'Hadar attack ships opened fire from 50 kilometers distance.
DS9 "Call to Arms"
In this episode, a Dominion fleet attacks Deep Space 9. Even when engaging a completely immobile target, the Dominion ships close to within several kilometers before opening fire.
The screenshot on the right shows the Dominion/Cardassian fleet approaching Deep Space 9 to the point of it taking up a significant fraction of the field of view. Yet in the following scene, Damar reports that they will not be in weapons range for another minute[1].
After the battle is joined, the attacking fleet continues to fight at extremely close ranges; however, even ranges of several hundred meters appear to be too great for Deep Space 9 targeting sensors to achieve a reasonable accuracy. On the left we can see a Cardassian shuttle flying straight towards Deep Space 9 central assembly. The shuttle doesn't change course or attempt to evade the incoming fire, yet Deep Space 9 only scores two grazing shots on it, thus failing to stop the craft.
Further evidence of limited accuracy comes from the end of the episode. As the Defiant and a Bird of Prey flee DS9, the Dominion fleet opens fire, and we see 11 shots fired without a single one hitting the fleeing ships. The shots can be seen at right, and -- as is immediately apparent -- the ships are flying in a tight formation without making any attempts to evade enemy fire. As before, the range is on the order of several hundred meters or several kilometers at most.
TNG "Conundrum"
Riker says they are still 55 seconds from "Optimal firing range in fifty five seconds" for the Lysian Central Command, even though they are practically on top of a stationary target that is both very large and very poorly defended (by Federation standards, although the crew up to that point had been deceived by an enemy of the Lysians that they were facing an opponent of equal strength to themselves).
The Lysian station is indeed quite large and the Enterprise-D is shown heading towards the station at approximately it's own 642 meter length each second. In 55 seconds, the Enterprise would travese nearly 36 km. This would make the Lysian Central Command absolutely gigantic since it subtends a large portion of the camera's field of view, even though it was so far away, thus the visuals for the scene itself may be considered suspect.
At any rate, clearly "optimal firing range" is not necessarily the full range capability of the ship, especially since the Enterprise crew was expecting to be facing a vastly superior opponent than what they actually encountered.
TNG "Yesterday's Enterprise"
Three un-cloaked Klingon Birds of Prey close to within a few kilometers before firing on the Enterprise. Likewise, the Enterprise, knowing they will be attacked by the Klingons, doesn't fire until the enemy is at close range (there is no political reason to delay firing, since the Federation is in a state of war with the Klingons in this alternate-timeline episode).
TNG "The Wounded"
This episode is often cited as evidence for long-range combat by major ST civilizations:
- DATA: The warship is three hundred thousand kilometers from the Phoenix. It is opening fire. The Phoenix has taken a direct hit ... the Phoenix is beginning evasive maneuvers ... it has positioned itself outside the weapons range of the opposing ship ... the Phoenix has powered up with both phasers and photon torpedoes ... the Phoenix is firing photon torpedoes.
As Data is speaking, the viewscreen shows a two-dimensional display of the battle. If this display is oriented to provide the most useful view of the battle (placing all three of the vessels being tracked in the same plane), then it shows the relative weapon ranges of the ships and the distance between the them. The display casts doubt on Data's description of the battle, since the viewscreen shows that the Phoenix is still well within weapons range of the Cardassian ship, which actually has greater range than the Phoenix if the display is accurate.
It should also be noted that the ships involved in the battle are travelling at warp speeds, so a gap of 300,000 km could easily drop to zero in less than a second. It may also be worth noting that the battle was conducted entirely with torpedoes, and the Cardassian ship was pursuing the Phoenix: the Phoenix would therefore have been running away from torpedoes fired by the Cardassian ship, while the Cardassian ship was running toward the torpedoes fired by the Phoenix, possibly explaining the "out of range" statement. [proof that the Cardassian ship fired on the Phoenix with photon torpedoes? Nowhere is it stated that the Cardassian ship used photon torpedoes, in fact the weapons used are never stated at all in that entire scene, only the Phoenix's]
The battle between the Enterprise and the Cardassian warship, Trager, earlier in the episode, further disproves any optimistic interpretation of Data's range description. As the screenshot to the left shows, the ships engage at a range of several hundred meters, nowhere near the supposed hundreds of thousands of kilometers. However this can be explained since the Enterprise was awaiting a meeting with the ship that attacked it. The Cardassians closed the distance no doubt as an abush ruse to catch the Federation starship off-guard. However the Enterprise was able to respond quickly and using accurate targetting of the Trager's shields and engines to disable it within seconds.
TNG "Q Who"
When the Enterprise is attacked by a Borg Cube, Picard orders Worf to target the source of the tractor beam and fire. Shockingly, it takes Worf four tries to hit the beam emitter from point-blank range; the first three shots aren't even close!
VOY "Equinox"
Voyager reportedly attacks the Equinox with phasers from 30,000 km away. Upon closer inspection of the episode, however, we find that no evidence of such range exists. On the contrary, the episode implies far shorter maximum ranges of Federation ships.
The relevant dialog:
- [Bridge]
- PARIS: Thirty thousand kilometres and closing.
- JANEWAY: Target their power core.
- [Equinox Bridge]
- GILMORE: Direct hit. Minor damage.
- RANSOM: Return fire.[1]
Since Janeway only instructed the crew to start targeting Equinox's power core at 30,000km and since there is a scene cut between the order and the first seen hit there is no way to determine how far away Voyager actually was when it started firing upon Equinox.
Further events in the episode suggest much lower ranges:
- RANSOM: Lay in a course through the planet's atmosphere. Sixty degree vector.
- [Bridge]
- JANEWAY: What the hell is he doing. Follow him!
- PARIS: Crossing the upper thermosphere.
- JANEWAY: Phasers.
- TUVOK: Shields are weakening. Thirty one percent, twenty nine.
- KIM: Inertial dampers are offline.
- CHAKOTAY: Captain, if we loose our shields well be attacked by the aliens. Captain!
- JANEWAY: Break off pursuit.
If Voyager were capable of scoring hits from anywhere near 30,000km, there would be no need to follow the Equinox into the atmosphere and risk damage due to atmospheric friction.
TNG "The Arsenal of Freedom"
Left in command of the Enterprise, Geordi takes the drive section of the ship into the atmosphere of the planet to lure a cloaked alien drone into following them. The drone pursues them into the atmosphere, where they are able to detect its wake and target it. If the drone were capable of attacking from a range of thousands of kilometers, it would not have needed to follow the Enterprise into the planet's atmosphere.
However earlier in the episode the very same drone is shown firing from a vastly greater distance, so far away that the beam disappears off to an infinity point, thus the drone was capable of far greater range.
"A Matter of Honor"
A klingon bird of prey is preparing to attack the Enterprise-D under the mistaken belief that the Enterprise is responsible for contaminating it with a subatomic lifeform destructive to their ship's hull. Riker is serving aboard as an exchange officer during this time, he gives advice to Kargan, the BoP's captain:
RIKER: You'll get only one shot.
KARGAN: We'll only need one. Stand by on phasers and torpedoes. Prepare to fire them simultaneously.
RIKER: I recommend you don't fire until you're within forty thousand kilometers.
KLAG: Why?
RIKER: It will cut down their response time.
This was part of a ruse on Riker's part to get within transporter range, but it does establish no less than 40,000 km as range, and nothing in the episode contradicts this since neither ship fired on the other.