In A New Hope, Luke turning off his targeting computer caused quite a stir. Yet when he shot his proton torpedoes, they seems to turn in mid flight to enter the exhaust port. Was this due to some mechanism of the torpedoes or was Luke using the Force to actually alter the torpedo's path?

I don't think Luke had nearly enough experience with the Force to alter the flight paths, but if the torpedoes could make that sharp a turn at the right moment, why was the targetting computer so important?

  • 5
    Not based on any sort of reference, but the impression I formed while watching the film was that the torpedoes were programmed to fly straight for a predetermined distance and then execute a 90 degree turn. In my mind that seemed like the only reasonable explanation for why the targeting computer was necessary: the torpedoes had to be launched at exactly the right position, otherwise they'd just smack into the hull of the Death Star. But again, that's just from my imagination.
    – David Z
    Jan 5, 2012 at 7:46
  • 12
    The real reason that Luke turned off his targetting computer.
    – John C
    Jan 5, 2012 at 13:12
  • 1
    To me, it almost looks like the torpedoes' trajectory is influenced by gravity. Certainly, an object as large as the Death Star would have gravity, but whether it would be enough to change the trajectory of a missile is a different question.
    – Martha
    Jan 5, 2012 at 18:08
  • I always thought that the torpedoes "banked" into the exhaust port; if you watch that cut, they seem to have some sort of energy shielding surrounding them which caused them to "glide" into the port instead of impacting onto it. It's still a one-in-a-million shot; perhaps more so because you have to not only be at the proper range but have the proper angle on the port to get them to slide in.
    – KeithS
    Jan 31, 2012 at 16:53
  • 1
    Following on from what KeithS said its, in my opinion, just a question of timing and letting the guided nature of the missiles, perhaps with energy shielding features, do their job of ‚locking on‘. Too soon or too late and the missiles land on the chassis of the ship, just right and they just glide in, bingo 😀 In this sense the force guides Luke when to release the torpedos and seems a likelier explanation. Having Luke additionally use the force to change their trajectory smacks of having too much control, a criticism more appropriately levelled at the Empire.. Sep 4, 2018 at 9:09

4 Answers 4


Luke had just been introduced to the Force within a period of what seems to be just hours (but would likely be less than a few days) and had no idea of the potential of the Force.

He was, though, used to flying and using computers and other targeting systems (there's no reference to him being such a good shot he didn't need targeting computers to bulls-eye womp-rats). So he went in to the battle flying as he always had, in the way he was comfortable: with all the tech turned on and paying attention to all of it.

It was only when Obi-Wan spoke to him that he started thinking about not using the targeting computer. While he seemed doubtful at first, he is hearing the voice of his dead mentor quite clearly, which would be enough proof there's power to the Force for him to make the leap of faith to trust Ben Kenobi and, by extension, trust himself as Kenobi obviously did.

The turn, or dive, as I like to think of it, for the torpedoes, could be due to a number of things. It's possible that he had some control over the torpedoes using flight controls in his X-Wing.

Another possibility is that the torpedoes are proton torpedoes and the port is ray-shielded, and the shielding could be negatively charged, which could change the course of the torpedoes without stopping them. (Also, just passing through the shielding could have disrupted the flight path of the torpedoes, which would have been taken into account when programming the targeting computers.)

But, considering this was a planned attack, it's also very likely that the torpedoes were pre-programmed, so as long as they were launched within a certain distance of the port and pointed right at the port, that onboard programming would provide some control over the course of the torpedoes.

There are a number of technical issues that could easily influence the behavior of the proton torpedoes, and it's likely the Alliance would have taken that into account when preparing the weapons and fighters for the attack.

  • I clarified the question a bit to highlight the concern of the torpedoes having any semblance of self guidance. Jan 5, 2012 at 0:26
  • The negatively charged ray shielding seems the most plausible. Can you find any kind of source for this? Jan 5, 2012 at 0:26
  • 1
    "there's no reference to him being such a good shot"? Do you mean "there's a reference"? Jan 6, 2012 at 5:38
  • Could Kenobi have done it?
    – Marriott81
    Apr 25, 2014 at 10:43

I think my answer from the related question seems somewhat applicable here, too.

In the fourth draft (the one just prior to filming) of the script, Lucas gives us a hint about how he envisioned the Proton Torpedoes working:

                Your approach will not be easy.  You
                must maneuver straight in
                down this shaft, level off in the
                trench and skim the surface to this
                point.  The target is only two meters
                across.  It will take a very precise
                hit at exactly ninety degrees to get
                into the reactor system.  And only a
                direct hit will set up a chain
                reaction.  The shaft is ray shielded,
                so you'll have to use proton torpedoes.

I think by "ninety degrees" that Lucas was probably imagining that the pilot had to be directly above the exhaust port in order for it to drop go all the way down into the reactor. That might make sense when you're writing something, but it's obviously harder to ignore the laws of inertia when someone asks you to animate it. (You may interpret it differently, though.)

The SFX team apparently took this problem and envisioned them more "realistically" as something akin to traditional bombs. You can see this in the movie for yourself in one of Dan O'Bannon's tactical displays:

enter image description here

It clearly shows the idea was that the pilot was supposed to "drop" the torpedoes into the exhaust port, like a real world bomb.

Indeed, even if you slow down the infamous shot in question, you can see that the torpedoes are supposed to be falling... it's the just animation happens too quickly you don't see it. (And the previous shot of them travelling in a straight line, like a laser, doesn't really help.)

I created this animated GIF, slowing down all 16 frames of the animation, so you can see this for yourself:

enter image description here

So it appears to be a somewhat inconsistent interpretation born out of probably what was only a rough idea in the script to begin with (Lucas was never one for getting bogged down in technical details of his universe), rather than anything deliberately thought out.

Indeed, judging from Luke's actions, it seems clear that he turns off his targeting computer in order to manually decide when to fire his torpedoes into the exhaust port. There doesn't appear to be any further input from him after that.

Maybe George Lucas could fix this issue in one last "Special Edition"? :) (Just kidding, please don't kill me.)

Expanded Universe Explanation

Of course, that's just one canon. If you're open to letting other authors interpret how Proton Torpedoes work, and are prepared to enter the murky (and often contradictory) "Expanded Universe", then there's more answers waiting for you.

Noting their apparently strange behaviour in the original movie, it seems that most EU authors have imagined Proton Torpedoes to be simple homing missiles with the additional ability of manual remote control.

Here's some samples from the EU novels:

  • X-Wing: Rogue Squadron (1996), Michael A. Stackpole
    "Corran switched over to proton torpedo target control."

  • Jedi Trial (2004), David Sherman and Dan Cragg
    "Gunnery officer, mark that target for proton torpedo salvo. Deactivate the homing system. Use line-of-sight guidance system. I want these babies dead on."

In the games (X-Wing, Rogue Squadron, etc.), however, they are treated differently yet again: More like standard slow-but-powerful homing missiles, with no manual guidance. In the X-Wing Miniatures board game they are also treated like homing missiles (requiring a player to "lock" on a target before they can be fired). This is more likely born out of the need for gaming mechanics, however.

Despite this general consensus about their behaviour, other EU sources are contradictory. For example, the aforementioned Jedi Trial states that Proton Torpedoes were first used in the "Clones Wars", yet Anakin's big yellow Starfighter at the end of The Phantom Menace is said to be equipped with them. Furthermore, Star Wars: Knights of the Old Republic II, set thousands of years before the events of the movies, makes mention of them as well.

Basically, with the EU you pretty much get to choose your canon, but most of the time they're considered to be homing missiles, with the ability for manual guidance. (With this interpretation, Luke turning off his targeting computer allowed him to manually guide the missiles down the exhaust port.)


Luke, at the time not being a master of the Force, could definitely not have altered the direction of the torpedos. He was more using the force to guide him as to where to shoot the torpedos.

The torpedos turning would be a mechanism of the torpedoes themselves or something to do with the way the exhaust port works.

  • s/defiantly/definitely/? Jan 5, 2012 at 0:12
  • 1
    definitely. unless Luke was being defiant towards something.
    – Xantec
    Jan 5, 2012 at 0:58
  • @Xantec -- well.... there was this little authority of the time known as the Empire... but who's counting them (much less being defiant towards them)? - oh, wait!! that's what you meant, right? Dec 29, 2014 at 13:51

Let me first respond to Martha's comment: "To me, it almost looks like the torpedoes' trajectory is influenced by gravity. Certainly, an object as large as the Death Star would have gravity, but whether it would be enough to change the trajectory of a missile is a different question."

The size of an object doesn't grant it gravity. The density of the object's core grants it gravity. There is probably more open space in the Death Star than there is of any other material that makes it up. The only gravity the Death Star possesses is that of artificial means so that everyone on the ship doesn't float around.

Now I know absolutely zero about the production of the movie, but what it looks like to me is they had no clue what they were doing considering special effects (not that I'm blaming them), didn't know how to accomplish two missiles entering the exhaust port, and compromised on filming rolling two ball bearings on a table and into a hole, then modifying the footage to make the ball bearings glow. In other words, I have to imagine that Luke was shooting specialty missiles like those mentioned by the original poster and by this comment written by David Z: "the impression I formed .... was that the torpedoes were programmed to fly straight for a predetermined distance and then execute a 90 degree turn." or else that Luke was just shooting straight and we have to use our imaginations considering the limited special effects

  • Unfortunately, density is mass over volume, so by your definition size is still involved. How much of a "pull" an object exerts depend on mass, and the strength other objects feel depend on how far away they are. All object have gravity, but most of the time this is very small. The Death Star would likely have a non-negligible gravity field just from the people on board, never mind the actual material used to make the thing... beyond that, the EU has these weapons as being guided, they could turn themselves just fine. And they turn in the presentation in the briefing. Apr 25, 2014 at 14:23
  • It's entirely feasible that the DS has artificial gravity and that artificial gravity field extends beyond the decks and the surface of the "moon."
    – RoboKaren
    Jul 22, 2014 at 14:05
  • Mass is what influences gravity. a super dense black hole is smaller but has more gravity than a larger but less dense star. The Death Star is, for all reality, hollow and filled with low mass/density air
    – user001
    Nov 19, 2015 at 13:54
  • Density isn't quite right. Gravity is mass/(distance from center)^2. See en.wikipedia.org/wiki/Shell_theorem
    – Navin
    Aug 13, 2019 at 6:44

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.