I have a question about how Interdictors work. We have seen ships jump relatively close to a planet which means in order for Interdictors to affect other ships especially at a distance, then they have to generate massive amounts of gravity. How are the crews of these ships able to breathe let alone move? Why doesn't the gravity generated attract other ships towards the Interdictors? I might be way off base, but could someone please help me with this?

  • 1
    First question has an answer here scifi.stackexchange.com/questions/68754/…. Perhaps you should drop it, because you have two questions in one, and one is a duplicate of an existing question.
    – TimSparrow
    Commented Mar 30, 2018 at 23:46
  • Thanks TimSparrow, I edited the question as you suggested.
    – First Last
    Commented Mar 31, 2018 at 0:27
  • 2
    @FirstLast - Interdictors have gravity projectors. They don't generate their own gravity field, they shoot one off into space; starwars.wikia.com/wiki/Gravity_well_projector
    – Valorum
    Commented Mar 31, 2018 at 0:39
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    From the link, "A gravity well projector was a powerful device affixed to an Interdictor vessel used to pull ships out of hyperspace. As a ship could not usually enter hyperspace when within a planet's gravitational pull, the gravity well projector mimicked the effect by creating a strong artificial gravity well known as an interdiction field." It creates a strong artificial gravity well. Even if they shot one into space, gravity is omnidirectional. It would still affect everyone on the ship due to proximity to the generators.
    – First Last
    Commented Mar 31, 2018 at 8:02
  • I suspect the only robust answer to "how does an Interdictor work" will turn out to be "very well, thank you".
    – Graham Lee
    Commented Mar 31, 2018 at 8:11

3 Answers 3


The interdiction field (artificial gravity well) does not need to be left on continuously in order to drag ships out of hyperspace -- it can be turned on and off quickly. Also, the required strength of the interdiction field depends on the speed of the ship, so slower ships don't require such a strong field. These properties were established in the canon novel Tarkin, in which an Interdictor was used by the Empire in an effort to recapture Tarkin's stolen ship, the Carrion Spike:

“The projectors are powering up to high gain, Governor Tarkin,” the commander said. “The field will be initiated, then disabled, in an effort to keep from dragging vessels other than the [Carrion Spike] from hyperspace. I should caution, however, that that may be unavoidable, given the heavy traffic in this system.”

“I understand, Commander,” Tarkin said. “Order your technicians to be judicious, nonetheless.”

“I will, sir. But the power setting of the gravity wells is dictated to some extent by the relative speed of the targeted ship, and, well, sir, to be blunt about it, there aren’t many as fast as the Carrion Spike.

p. 192

Presumably, an interdiction field only needs to be about as strong as the gravity humans are accustomed to on a planet (i.e. about 1g in our universe). And in the event that the interdiction field needs to be considerably stronger to catch faster moving ships its strength could be lowered after only a few seconds -- the crew of the Interdictor might temporarily black out but would regain consciousness shortly after (as if they were flying in a fighter jet pulling a high g turn).

Why doesn't the gravity generated attract other ships towards the Interdictors?

It does. An early use of an interdiction field caused collisions when the Interdictor lost control of the field and the field became too strong:

The countdown had just reached T minus five when Tarkin was yanked forward, nearly completely off his feet. Fearing another lurch he spread his hands wide and so was kept from being slammed headfirst into the closest viewport panel. Klaxons began to howl throughout the suddenly trembling command bridge as the giant ship groaned and lurched yet again in the direction of the distant Interdictors. Struggling to remain upright, Tarkin caught a glimpse of the middle-distance frigates and pickets being pulled forward, almost as if accelerating.

“Commander,” he shouted into the headset mouthpiece, “the field is too powerful!”

“Working on it, sir,” the commander said with equal volume. “It’s the Immobilizer. The overcurrent resistors failed to prevent the gravitic systems from redlining—”

The comlink connection broke.

Close to the Interdictors, ships began to appear where there had only been star-filled space. Tarkin turned from the forward bay and stumbled back to the data pit to study the magnified view on one of the screens. First to drop out of hyperspace was an outmoded, saucer-shaped YT-1000 freighter, followed by two angular transports and a lustrous space yacht. Then another freighter winked into visibility, followed by two passenger vessels.

Abruptly, Tarkin felt as if he’d been shoved toward the rear of the bridge. With the interdiction field neutralized, the ships that had been caught in the invisible web began to whirl out of control. Two of the ships collided and drifted out of view. The magnification screen showed the sublight engines of other ships flashing, but the ships barely had a chance to flee or correct their spins when the field re-initiated, capturing them once again. Tarkin spread his legs wide in an effort to balance himself; then his eyes went wide as well as he turned to face the viewports. Listing on its port side, an enormous ship that more resembled something grown than built decanted, broadsiding the Detainer CC-2200 before careening into a spin that left its dorsal surface impaled on the Interdictor’s sloping bow.

p. 193

Again, presumably the interdiction field would not normally be set so high that ships would collide with the Interdictor quickly and/or without being able to thrust away from the Interdictor.


Why doesn't the gravity generated attract other ships towards the Interdictors?

It does, if not controlled correctly. There is a specific instance of this in the animated series Star Wars Rebels. In the second-season episode, "Stealth Strike", members of the Rebellion first discovered an Interdictor while trying to rescue some teammates who had been captured by it (they were pulled out of hyperspace by the gravity well when they traveled too close to its top-secret testing field). In order to escape it, they managed to sneak around to the control system and re-calibrate/direct the gravity "beam" (it's actually referred to specifically as a "gravity well" in the episode) in order to drag all the surrounding Imperial ships into collision with the Inderdictor, breaking its hold on the Rebel ship and allowing them to jump away.

And as others have said, there are more examples of this in the Tarkin novel.

Also, and once again as others have said, it makes total sense that the gravity created by this ship would not have to be ridiculously strong to pull a ship out of hyperspace, probably only about the same as that of normal, humanoid-inhabited planets. That's why interstellar pilots have to be very careful that they don't get too close to a planet or star while traveling within hyperspace, as it would probably pull them out. I'm even going to theorize that this may be the reason why jumping to hyperspace within the atmosphere is so dangerous/people are so shocked when it's even mentioned as a possibility. So when they want to pull a ship out of hyperspace, they specifically position the Interdictor near hyperspace lanes they know their victims will be traveling along, and boom! Now they're out and at the mercy of the Empire.

  • Good answer. +1 from me! I also deleted our discussion in the comments on my answer.
    – Null
    Commented Apr 6, 2018 at 22:55

It's mentioned in one of its very first (if not the first) appearance in Legends, in Heir to the Empire, that the Interdictor generates a cone of gravity, rather than a sphere. This, combined with the fact that the projectors are on the very bottom of the hull, suggests that the cone can simply be pointed in such a way that it doesn't intersect the Interdictor itself or any nearby ships.

Another interesting Legends tidbit: in Solo Command, it's shown that an Interdictor's gravity generators can be reversed, turning them into giant repulsors, for a brief period. (It has unspecified ill effects on the internal gravity, though, and there are apparently safeties in place to prevent this from being done casually.) The Stellar Web uses this trick to evade a damaged Imperial Star Destroyer on a collision course, after the point where its main engines wouldn't have turned it fast enough.

  • Except that's not how gravity works. It's omnidirectional, how then can an Interdictor generate a cone of gravity?
    – First Last
    Commented May 14, 2018 at 11:24
  • @FirstLast Well, ultimately, the name of the genre is science fiction. There are numerous cases of directed gravity in Star Wars: artificial gravity, dovin basals, even repulsorlifts. I don't know how it works, just that it does.
    – Cadence
    Commented May 14, 2018 at 17:59

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