In the proposed tactic, a starship sets a course to fly past an enemy vessel, starting out of weapons range from the target (perhaps light-hours or more away). It then approaches the target at warp speed. Once the enemy vessel is within weapon range, the starship fires its weapons as it flies by the target. Supposedly, the starship could perform an alpha strike while the enemy is unable to return fire.
The critical problem with warp strafing is relative speed, a topic covered in Junior High School physics courses. Suppose car A approaches car B while at 50 km/h. Further suppose car B is traveling at 49 km/h in the same direction. The relative speed between car A and car B is 1 km/h. However, a car traveling at 100 km/h compared to a car traveling at 20 km/h in the same direction is truly approaching at a relative speed of 80 km/h.
Relative speed is important because Star Trek starships of every faction have shown difficulty locking onto relatively slow and predictable targets, let alone targets travelling at relative speeds in excess of lightspeed. In short, the evidence indicates that Star Trek ships could not hit their targets if they attempted a warp strafe.
Furthermore, generously accepting the stated ranges of as much as 300,000 km for Star Trek weapons, a starship attempting to warp-strafe a sublight target would be in range for no more than two seconds and probably far less (since warp-driven starships are capable of traveling at thousands of times the speed of light). An attacker would only be able to use a tiny fraction of its firepower on each fly-by, meaning that it would probably take hundreds or thousands of strafing runs to significantly affect an armored or shielded target.
Alternatives and Countermeasures
Warp strafing would be ineffectual against stationary targets. If a target were stationary, the attacking starship could simply stand off and fire from light-minutes away. Its beams and missiles would eventually reach the target, but the stationary target could not effectively return fire, since the mobile starship could perform simple evasive maneuvers to avoid shots that would take minutes to reach it.
Secondly, stationary and heavily defended targets such as battle stations, weapons platforms and fortified planets could track the attacker with faster-than-light sensors. Any vessel attempting this tactic would move in a predictable straight line, a so-called "attack run." Unless the attacking vessel further complicates the attack run with changes of course and acceleration, the defender could track the attacking vessel just as easily as the attacking vessel could track it, with the added advantage of being stationary and using more power for shields and weapons. The attacker would have to fly through a barrage of defensive fire to complete its strafing run, with much of its power devoted to propulsion instead of weapons and shields.
If warp strafing were really such a powerful tactic, we would expect to see it used against stationary targets like Deep Space Nine. DS9 has been attacked repeatedly by the Cardassians, Klingons, and the Dominion, but none of them have employed warp-strafing attacks against the station.
In summary, warp strafing requires the attacker to have far more advanced propulsion, sensor and weapons technology than the defender. With such advantages, a more conventional approach would be at least as successful. The attacker could simply stay at stand-off range and pelt the defender with beams and missiles, negating the need for a dangerous warp-speed approach.
Elaan of Troyius
Trekkie debaters often cite the TOS episode "Elaan of Troyius" as an example of a canonical warp strafe, saying a Klingon vessel makes repeated strafing runs against the Enterprise, which is limited to impulse speed because the warp core was sabotaged. There are several problems with this example, however.
- Sulu counts down the range between the vessels in tens of thousands of kilometers over several seconds, indicating the relative velocity between the starships is less than lightspeed. Episodes like "Mudd's Women" show that it is possible to achieve warp speed for a limited time without a functioning warp core, so it's possible that the Enterprise is engaging in FTL maneuvers using power from its impulse engines.
- The low-end estimate for the klingon ship's speed on a warp 7 attack run is 343c. Assuming a disruptor range of a light-second, the klingon ship would be in range for less than 3 milliseconds on a "strafing" run against a sublight target. The Klingon weapon discharges took far longer.
- Maneuvers at warp speed will arc across millions of kilometers of space, at minimum. The klingon ship could not reasonably warp to an unshielded side of the Enterprise and then turn to bring its forward weapons to bear and still be in disruptor range if it's relative speed was greater than lightspeed the entire time.
In light of these difficulties, it seems more plausible that the klingon cruiser is using warp to position itself for a shot at the weakened shield of the Enterprise, slowing to match speeds while it brings its weapons to bear and fires, then accelerating away again before the Enterprise can shoot back with photon torpedoes (which would not be weakened by the loss of warp power on the Enterprise). This is undeniably effective, but it does not constitute firing on a sublight target while moving at warp speed.
Journey to Babel
TOS "Journey to Babel" is also cited as an example of warp strafing. The Enterprise is attacked by an unidentified vessel with modified warp engines, giving it greater speed than the Enterprise by a couple of warp factors. It repeatedly approaches the Enterprise at Warp 8 and rakes the ship with phaser fire, but the Enterprise is unable to effectively return fire against the fast-moving attacker. Kirk is eventually forced to trick the enemy ship into approaching at sublight speed in order to deal with it.
The fact that the enemy approaches at sublight speed when the Enterprise is "stopped" indicates that a warp strafe would not be plausible against a "stationary" target.
The Ultimate Computer
In TOS "The Ultimate Computer", the Enterprise engages in mock battles and, later, real battle against other Constitution-class starships. The Enterprise engages them at warp speed, maneuvering to attack and then maneuvering away without taking return fire. A "warp strafing" explanation in this episode has the following issues:
- The other ships have exactly the same capabilities as the Enterprise: they are not restricted to impulse power the way the Enterprise was in "Elaan of Troyius".
- The M5 computer allows the Enterprise to instantly turn command decisions into action, avoiding the delays of relaying orders and keying them into consoles. This reaction time advantage may be all that is necessary for the M5 to effectively employ its hit-and-run strategy.
The Picard Maneuver
Trekkies sometimes cite the Picard Maneuver (TNG "The Battle") as an example of warp strafing, but the Picard Maneuver specifically involves accelerating from sublight speed to high warp and then dropping back out of warp before firing weapons.
Star Trek Into Darkness reveals that the only Federation starship capable of engaging in combat at warp speed is the USS Vengeance, and even then it was only tried against another target traveling at warp, meaning their relative speed was not very high. It follows that warp strafing is not a viable tactic in the "new Trek" timeline.