# Most annoying sci-fi TV/movie tropes **URL:** \ **Category:** Cafe Society\ **Created:** [January 5, 2016, 7:35pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257 "2016-01-05T19:35:27Z")\ **Posts on this page:** 16\ **Page:** 11
**Author:** ![AncientHumanoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ancienthumanoid/32/278_2.png) [@AncientHumanoid](https://boards.straightdope.com/u/AncientHumanoid)\ **Post date:** [January 19, 2016, 11:48pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/201 "2016-01-19T23:48:48Z")
What’s your vector, Victor? ---
**Author:** ![msmith537](https://avatars.discourse-cdn.com/v4/letter/m/d9b06d/32.png) [@msmith537](https://boards.straightdope.com/u/msmith537)\ **Post date:** [January 20, 2016, 1:59pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/202 "2016-01-20T13:59:31Z")
Phasers and blasters and lightsabers are not “lasers” as we understand them. In Star Wars, my understanding is that they are closer high energy plasma contained and projected by something similar to their force field technology. IOW, more like a super-hot plasma arc welding torch contained by magic and projected at some fraction of the speed of light. ---
**Author:** ![Peremensoe](https://avatars.discourse-cdn.com/v4/letter/p/ce7236/32.png) [@Peremensoe](https://boards.straightdope.com/u/Peremensoe)\ **Post date:** [January 20, 2016, 2:21pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/203 "2016-01-20T14:21:34Z")
> [@Trinopus](#): > > …you have to work at cancelling what you’re already doing as well as establishing what you want to do. Otherwise, as you say, you’ll end up with the sum of the two, and not merely the desired result. You plot your course in such a way that progressive summing of changes to thrust _brings_ you to the direction you want. > [@Lemur866](#): > > You’re on skates. You go forward. You want to change direction you dig in your skates and suddenly you’re going in another direction but you’ve preserved your speed. Now imagine that you’re on the ice but you don’t have skates, just a rocket. You’re headed toward the wall and are going to crash. Can you change direction and do a U-turn using your rocket? No you cannot. The only thing you can do is point your rocket at the wall and turn it on until you slow down and eventually stop relative to the wall. Sure I can U-turn, given room. Tilt my thrust over to one side. Change my course into a sweeping curve, so that I’m headed toward the wall at increasingly oblique angles, then parallel to it for an instant, then increasingly away. ---
**Author:** ![Skald\_the\_Rhymer](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Skald\_the\_Rhymer](https://boards.straightdope.com/u/Skald_the_Rhymer)\ **Post date:** [January 20, 2016, 3:50pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/204 "2016-01-20T15:50:30Z")
> [@msmith537](#): > > Phasers and blasters and lightsabers are not “lasers” as we understand them. In Star Wars, my understanding is that they are closer high energy plasma contained and projected by something similar to their force field technology. IOW, more like a super-hot plasma arc welding torch contained by magic and projected at some fraction of the speed of light. The important word in this post is “magic.” ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [January 20, 2016, 6:45pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/205 "2016-01-20T18:45:51Z")
> [@Peremensoe](#): > > You plot your course in such a way that progressive summing of changes to thrust _brings_ you to the direction you want. Why? If you want to change your course to +30°/-50° relative, you turn your vehicle to something like a +120°/-170° orientation (adjusted to compensate for the local gravitational gradient and density of regional dust and gas) and burn your thrusters at a force output that your vessel and its occupants will tolerate until your course is what you want. Your path will trace a curve from your initial course into your desired course. You will probably roll to a position that minimizes stuff flying all over the place inside during the burn, then probably pitch and yaw into alignment with your final course once the burn is finished. To a nearby observer, it would bear very little resemblance to flying in air. > [@](#): > > Sure I can U-turn, given room. Tilt my thrust over to one side. Change my course into a sweeping curve, so that I’m headed toward the wall at increasingly oblique angles, then parallel to it for an instant, then increasingly away. Again, just flip 180° and burn. You cancel your forward vector (decelerate) to “zero” (there is really no such thing as “stopped dead in space”) then continue to burn (accelerate) until you are moving as fast as you want back to whence to came. Sweeping out a curve to reverse direction is a waste of time and probably uses more fuel than just flipping around. ---
**Author:** ![Peremensoe](https://avatars.discourse-cdn.com/v4/letter/p/ce7236/32.png) [@Peremensoe](https://boards.straightdope.com/u/Peremensoe)\ **Post date:** [January 20, 2016, 8:41pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/206 "2016-01-20T20:41:35Z")
> [@eschereal](#): > > If you want to change your course … you turn your vehicle … and burn your thrusters … until your course is what you want. Your path will trace a curve from your initial course into your desired course. That’s right. > [@eschereal](#): > > Again, just flip 180° and burn. You cancel your forward vector (decelerate) to “zero” (there is really no such thing as “stopped dead in space”) then continue to burn (accelerate) until you are moving as fast as you want back to whence to came. Sweeping out a curve to reverse direction is a waste of time and probably uses more fuel than just flipping around. But maybe I don’t _want_ to just slow and reverse course on a line. There might be photon torpedoes on my tail. The post I was addressing claimed that I couldn’t do anything but. ---
**Author:** ![Trinopus](https://avatars.discourse-cdn.com/v4/letter/t/2bfe46/32.png) [@Trinopus](https://boards.straightdope.com/u/Trinopus)\ **Post date:** [January 20, 2016, 11:01pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/207 "2016-01-20T23:01:23Z")
> [@Peremensoe](#): > > You plot your course in such a way that progressive summing of changes to thrust _brings_ you **to the direction you want**. . . . > [@eschereal](#): > > Why? If you want to change your course to +30°/-50° relative, you turn your vehicle to something like a +120°/-170° orientation (adjusted to compensate for the local gravitational gradient and density of regional dust and gas) and burn your thrusters at a force output that your vessel and its occupants will tolerate **until your course is what you want**. . . . (Bolding mine.) I think you’re both saying the same thing! ---
**Author:** ![Declan](https://avatars.discourse-cdn.com/v4/letter/d/ecae2f/32.png) [@Declan](https://boards.straightdope.com/u/Declan)\ **Post date:** [January 20, 2016, 11:11pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/208 "2016-01-20T23:11:15Z")
> [@Peremensoe](#): > > That’s right. > > But maybe I don’t _want_ to just slow and reverse course on a line. There might be photon torpedoes on my tail. > > The post I was addressing claimed that I couldn’t do anything but. Sorry, rule of 4. Burn to start, burn to stop, burn to new vector, burn to stop. Newton, its the law. Declan ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [January 20, 2016, 11:37pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/209 "2016-01-20T23:37:50Z")
> [@Trinopus](#): > > (Bolding mine.) > > I think you’re both saying the same thing! I interpreted what **Permensoe** as a sequence of small burns, changing direction a bit at a time, rather than a single long burn. That seemed just silly to me. ---
**Author:** ![Pushkin](https://avatars.discourse-cdn.com/v4/letter/p/ee59a6/32.png) [@Pushkin](https://boards.straightdope.com/u/Pushkin)\ **Post date:** [January 23, 2016, 11:28pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/210 "2016-01-23T23:28:39Z")
Does sci-fi use the phrase “Crude… but effective” more often than any other genre? Usually delivered by someone frowning. Try something else, like someone smiling and saying “yeah, this’ll work!” ---
**Author:** ![iljitsch](https://avatars.discourse-cdn.com/v4/letter/i/77aa72/32.png) [@iljitsch](https://boards.straightdope.com/u/iljitsch)\ **Post date:** [January 24, 2016, 5:58pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/211 "2016-01-24T17:58:32Z")
Hm, isn’t that just a Seven-of-Nine-ism? ---
**Author:** ![Irishman](https://avatars.discourse-cdn.com/v4/letter/i/b487fb/32.png) [@Irishman](https://boards.straightdope.com/u/Irishman)\ **Post date:** [January 24, 2016, 9:37pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/212 "2016-01-24T21:37:24Z")
> [@terentii](#): > > Also BTW, reversing course by firing your thrusters in the opposite direction requires that you negate your “forward” motion before you start moving “backwards.” This is a great way to both waste energy and create enormous positive G forces. > > Seems to me that an Immelmann, in which you re-vector rather than cancel out your existing forces, would indeed be a much more elegant solution. > [@terentii](#): > > Yes, and you’d use thrusters to re-vector your motion, unless your warp field could be reconfigured somehow. The result would be the banking maneuvers we see the \*Enterprise \*perform. Once again, there is no way for thrusters to revector your motion to conserve your energy and momentum. If you wish to go back the way you came, the most direct method is also the most fuel conservative method. You flip your vehicle, aim your main engines the direction you are traveling, and thrust until you are going back the way you came. Using your thrusters to change your direction incrementally, point some to left, thrust, point more to the left, thrust, etc, just expends more fuel. You are wasting energy. Now if you are being chased by photon torpedos, there is benefit to not staying in your same line of motion. But that’s not the same thing as the simplest, easiest, most energy efficient way to turn around. If you have a planetary object nearby, you can use the gravity of that object to give you a turn. But without some outside force to work with, the most energy efficient solution is inverting your vehicle and thrusting backwards. No “banking”. > [@Peremensoe](#): > > Sure I can U-turn, given room. Tilt my thrust over to one side. Change my course into a sweeping curve, so that I’m headed toward the wall at increasingly oblique angles, then parallel to it for an instant, then increasingly away. Depends on the thrust and the amount of time/space in which to work. You start your gradual banking thrust, you are actually adding to your speed toward the wall. The minimum you want is to point parallel to the wall, but that still leaves you all your forward velocity into the wall, just adds sideways velocity to smear you along the wall as you impact. The fastest, most effective way to prevent wall impact is to point your thrusters directly at the wall and thrust at max power. Anything else is trading braking for some other objective. Vectoring will not save fuel, it will waste it. ---
**Author:** ![stosh](https://avatars.discourse-cdn.com/v4/letter/s/e95f7d/32.png) [@stosh](https://boards.straightdope.com/u/stosh)\ **Post date:** [January 26, 2016, 9:11pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/213 "2016-01-26T21:11:40Z")
It’s been said before, but I like how many times a problem is solved by our hero beating up someone in a fistfight. Remember the sword man in the “Indy” movie who was waving around his sword and got shot for his trouble. Also, I think" impossible" is a pretty strong word for the workings of “alien” weapons or space craft. We have things that would seem “impossible” not all that long ago. Until, we meet “aliens”, we don’t know what they can or cannot do. ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [January 26, 2016, 10:30pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/214 "2016-01-26T22:30:45Z")
> [@stosh](#): > > It’s been said before, but I like how many times a problem is solved by our hero beating up someone in a fistfight. Remember the sword man in the “Indy” movie who was waving around his sword and got shot for his trouble. > Also, I think" impossible" is a pretty strong word for the workings of “alien” weapons or space craft. We have things that would seem “impossible” not all that long ago. > Until, we meet “aliens”, we don’t know what they can or cannot do. Since the first thrown rock small arms have been aimed manually, and all our experience with projectiles is that they don’t always hit their targets; that may change. The weapons of the future might not be beam weapons or hyper-velocity projectiles, but something that changes the very nature of firefights: a semi-intelligent auto-aimer that allows you to shoot as fast and as accurately as you can point your eyes and designate “target” to the firing computer. Consider how different wars might be if soldiers _ **all but never miss** _. ---
**Author:** ![AncientHumanoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ancienthumanoid/32/278_2.png) [@AncientHumanoid](https://boards.straightdope.com/u/AncientHumanoid)\ **Post date:** [January 26, 2016, 10:44pm UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/215 "2016-01-26T22:44:12Z")
> [@Lumpy](#): > > Since the first thrown rock small arms have been aimed manually, and all our experience with projectiles is that they don’t always hit their targets; that may change. The weapons of the future might not be beam weapons or hyper-velocity projectiles, but something that changes the very nature of firefights: a semi-intelligent auto-aimer that allows you to shoot as fast and as accurately as you can point your eyes and designate “target” to the firing computer. Consider how different wars might be if soldiers _ **all but never miss** _. Moties did it. ---
**Author:** ![Balance](https://avatars.discourse-cdn.com/v4/letter/b/ccd318/32.png) [@Balance](https://boards.straightdope.com/u/Balance)\ **Post date:** [January 27, 2016, 12:35am UTC](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257/216 "2016-01-27T00:35:57Z")
> [@Lumpy](#): > > Since the first thrown rock small arms have been aimed manually, and all our experience with projectiles is that they don’t always hit their targets; that may change. The weapons of the future might not be beam weapons or hyper-velocity projectiles, but something that changes the very nature of firefights: a semi-intelligent auto-aimer that allows you to shoot as fast and as accurately as you can point your eyes and designate “target” to the firing computer. Consider how different wars might be if soldiers _ **all but never miss** _. In a thread about weapons missing in Star Trek, I [argued](http://boards.straightdope.com/sdmb/showpost.php?p=17199041&postcount=23) that the reason auto-aim wasn’t used was because of ECM (electronic countermeasures) escalation. Against enemies with roughly equal tech, ECM kept pace with auto-aim effectively enough to make it useless or actively detrimental. Eventually, it was dropped from the design of most standard-issue weapons. [Previous page](https://boards.straightdope.com/t/most-annoying-sci-fi-tv-movie-tropes/742257.md?page=10)