# Orderinng 'evasive maneuvers' a recipe for disaster? **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [July 13, 2016, 7:45pm UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841 "2016-07-13T19:45:58Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Cardigan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cardigan/32/187_2.png) [@Cardigan](https://boards.straightdope.com/u/Cardigan)\ **Post date:** [July 13, 2016, 7:45pm UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/1 "2016-07-13T19:45:58Z")
I have the impression that anytime in a sci fi universe a commander orders ‘evasive maneuvers’ it’s ultimately not going to work. And sooner, rather than later, you’re going to end up with main power down and only life support functioning, trying to communicate surrender terms with whatever alien nasty it was that blasted you. The key here is _ordering_ evasive maneuvers. Evasive maneuvers will work wonderfully and your spaceship will successfully weave and spin through laser blasts without ever getting hit almost every time so long as you just do it and don’t have someone order it. ---
**Author:** ![carnivorousplant](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnivorousplant/32/3563_2.png) [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)\ **Post date:** [July 13, 2016, 7:48pm UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/2 "2016-07-13T19:48:11Z")
Does waving hands at the helmsman count? ---
**Author:** ![Cardigan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cardigan/32/187_2.png) [@Cardigan](https://boards.straightdope.com/u/Cardigan)\ **Post date:** [July 13, 2016, 7:55pm UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/3 "2016-07-13T19:55:26Z")
I believe wild gesticulations on the bridge would be preferable to actually uttering those fateful words…evasive maneuvers. ---
**Author:** ![carnivorousplant](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnivorousplant/32/3563_2.png) [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)\ **Post date:** [July 13, 2016, 8:01pm UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/4 "2016-07-13T20:01:47Z")
How about suggestions? "Mr. Sulu, I would not object if you would like to make evasive maneuvers.? ---
**Author:** ![G0sp3l](https://avatars.discourse-cdn.com/v4/letter/g/c68b51/32.png) [@G0sp3l](https://boards.straightdope.com/u/G0sp3l)\ **Post date:** [July 13, 2016, 8:40pm UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/5 "2016-07-13T20:40:54Z")
It’s a well known fact that “evasive maneuvers” are a ploy to trick the enemy into thinking you’re crippled. That way the aliens (who only maneuver in two dimensions) will stop in weapons range. Allowing you to hack their systems and order the ships shields to drop. MONTALBAAAAAAAN! ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [July 13, 2016, 11:14pm UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/6 "2016-07-13T23:14:56Z")
> [@Cardigan](#): > > The key here is _ordering_ evasive maneuvers. Evasive maneuvers will work wonderfully and your spaceship will successfully weave and spin through laser blasts without ever getting hit almost every time so long as you just do it and don’t have someone order it. The important thing is you should never try evasive maneuvers with your engines at regular setting. Make sure to call your engineer first and tell him you need more power. He’ll tell you some nonsense about the engines being overloaded and they’re going to explode - just ignore him, that stuff never happens. ---
**Author:** ![RealityChuck](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/realitychuck/32/195_2.png) [@RealityChuck](https://boards.straightdope.com/u/RealityChuck)\ **Post date:** [July 14, 2016, 1:28am UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/7 "2016-07-14T01:28:00Z")
In 1915, the liner Lusitania took evasive maneuvers near the coast of the UK. It put them broadside to a German sub, making it an easy target. Didn’t work out ---
**Author:** ![snfaulkner](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snfaulkner/32/433_2.png) [@snfaulkner](https://boards.straightdope.com/u/snfaulkner)\ **Post date:** [July 14, 2016, 1:57am UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/8 "2016-07-14T01:57:17Z")
“Captain, incoming torpedoes!” “TAKE EVASIVE MANEUVERS!” “torpedoes evaded” end scene… kinda boring, eh? ---
**Author:** ![Balance](https://avatars.discourse-cdn.com/v4/letter/b/ccd318/32.png) [@Balance](https://boards.straightdope.com/u/Balance)\ **Post date:** [July 14, 2016, 2:10am UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/9 "2016-07-14T02:10:48Z")
In our [Why Weapons Miss in Star Trek](http://boards.straightdope.com/sdmb/showthread.php?t=718436) thread, I pointed out that manual aiming of ship-to-ship weapons at the speeds and distances involved in space combat would generally be impractical. While the _decision_ to fire comes from whoever is in command, the actual firing solutions must be computer-assisted. A battle is a duel between the ships’ computers, as they analyze movements, detect (and deploy) countermeasures, and jockey for an edge. Each shot is a complex speed-chess match. If the tech level on each side is about equal, and each computer knows the basics of the other ship’s capabilities, this tends to result in endurance matches, because the most consistent advantage a ship has is the tiny slice of time between firing and the enemy detecting the incoming attack. That edge is why most attacks end up hitting. That’s where the crazy biologicals riding around in the computer’s ship come in. They’re entropy sources. Ordering “evasive maneuvers” is a morale-friendly way of saying, “Our computer can’t dodge them, and I don’t think we’re going to win the endurance race.” It’s a gambit that injects random, usually tactically suboptimal movements into the computer’s calculations in an effort to make it less predictable to the enemy computer. It’s like the firing detection gap–you have a tiny edge, because _your_ computer knows you’re going to do something stupid before the enemy does. Of course, you usually get pounded anyway. That’s only to be expected, since you don’t order such a boneheaded gambit when things are going your way. But if you’re at a disadvantage already, it’s a gamble that may win you a little extra time to find a way out. ---
**Author:** ![carnivorousplant](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnivorousplant/32/3563_2.png) [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)\ **Post date:** [July 14, 2016, 2:15am UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/10 "2016-07-14T02:15:57Z")
> [@Balance](#): > > manual aiming of ship-to-ship weapons at the speeds and distances involved in space combat would generally be impractical. While the _decision_ to fire comes from whoever is in command, the actual firing solutions must be computer-assisted. A battle is a duel between the ships’ computers, as they analyze movements, detect (and deploy) countermeasures, and jockey for an edge. Poul Anderson writes about that, with the added difficulty of phasing in and out of FTL. ---
**Author:** ![Balance](https://avatars.discourse-cdn.com/v4/letter/b/ccd318/32.png) [@Balance](https://boards.straightdope.com/u/Balance)\ **Post date:** [July 14, 2016, 2:25am UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/11 "2016-07-14T02:25:17Z")
> [@carnivorousplant](#): > > Poul Anderson writes about that, with the added difficulty of phasing in and out of FTL. Yep. Welcome to a 4D chess match, with a time limit measured in picoseconds. ---
**Author:** ![Jragon](https://avatars.discourse-cdn.com/v4/letter/j/e19b73/32.png) [@Jragon](https://boards.straightdope.com/u/Jragon)\ **Post date:** [July 14, 2016, 2:41am UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/12 "2016-07-14T02:41:01Z")
> [@Balance](#): > > In our [Why Weapons Miss in Star Trek](http://boards.straightdope.com/sdmb/showthread.php?t=718436) thread, I pointed out that manual aiming of ship-to-ship weapons at the speeds and distances involved in space combat would generally be impractical. While the _decision_ to fire comes from whoever is in command, the actual firing solutions must be computer-assisted. A battle is a duel between the ships’ computers, as they analyze movements, detect (and deploy) countermeasures, and jockey for an edge. Each shot is a complex speed-chess match. If the tech level on each side is about equal, and each computer knows the basics of the other ship’s capabilities, this tends to result in endurance matches, because the most consistent advantage a ship has is the tiny slice of time between firing and the enemy detecting the incoming attack. That edge is why most attacks end up hitting. > > That’s where the crazy biologicals riding around in the computer’s ship come in. They’re entropy sources. Ordering “evasive maneuvers” is a morale-friendly way of saying, “Our computer can’t dodge them, and I don’t think we’re going to win the endurance race.” It’s a gambit that injects random, usually tactically suboptimal movements into the computer’s calculations in an effort to make it less predictable to the enemy computer. It’s like the firing detection gap–you have a tiny edge, because _your_ computer knows you’re going to do something stupid before the enemy does. > > Of course, you usually get pounded anyway. That’s only to be expected, since you don’t order such a boneheaded gambit when things are going your way. But if you’re at a disadvantage already, it’s a gamble that may win you a little extra time to find a way out. Also, it’s tremendously irresponsible to fire weapons in space without computer assistance because Sir Isaac Newton is the [deadliest son of a bitch in space](https://www.youtube.com/watch?v=hLpgxry542M) ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [July 14, 2016, 4:21am UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/13 "2016-07-14T04:21:46Z")
> [@Balance](#): > > That’s where the crazy biologicals riding around in the computer’s ship come in. They’re entropy sources. Ordering “evasive maneuvers” is a morale-friendly way of saying, “Our computer can’t dodge them, and I don’t think we’re going to win the endurance race.” It’s a gambit that injects random, usually tactically suboptimal movements into the computer’s calculations in an effort to make it less predictable to the enemy computer. No, evasive maneuvers really do work. Let’s say you have a weapon that takes thirty seconds from the time it’s launched to the time it arrives at the target. To hit the target, you have to predict where it will be in thirty seconds. That’s pretty easy if the target is traveling in a straight line. But evasive maneuvers are an effective defense. If you’re making a series of constant random course changes, your opponent won’t be able to predict where you’ll be in thirty seconds. ---
**Author:** ![Velocity](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/velocity/32/18006_2.png) [@Velocity](https://boards.straightdope.com/u/Velocity)\ **Post date:** [July 14, 2016, 4:24am UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/14 "2016-07-14T04:24:57Z")
> [@Little\_Nemo](#): > > No, evasive maneuvers really do work. Let’s say you have a weapon that takes thirty seconds from the time it’s launched to the time it arrives at the target. To hit the target, you have to predict where it will be in thirty seconds. That’s pretty easy if the target is traveling in a straight line. But evasive maneuvers are an effective defense. If you’re making a series of constant random course changes, your opponent won’t be able to predict where you’ll be in thirty seconds. But isn’t the weapon continuously tracking the target’s new whereabouts, and adjusting path accordingly? ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [July 14, 2016, 4:49am UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/15 "2016-07-14T04:49:11Z")
> [@Velocity](#): > > But isn’t the weapon continuously tracking the target’s new whereabouts, and adjusting path accordingly? Only if you have a weapon that can track its target and make course changes. A laser beam can’t do that; it just goes where you point it. ---
**Author:** ![Velocity](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/velocity/32/18006_2.png) [@Velocity](https://boards.straightdope.com/u/Velocity)\ **Post date:** [July 14, 2016, 4:54am UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/16 "2016-07-14T04:54:07Z")
> [@Little\_Nemo](#): > > Only if you have a weapon that can track its target and make course changes. A laser beam can’t do that; it just goes where you point it. A laser, though, being light, would reach its target pretty much instantaneously. And even if there were some distance in between, the target cannot know that it is being painted by a laser until it is being painted by a laser. Nothing can travel faster than light, and so there is no way for the target to be notified that it’s being hit by a laser until the laser hits. ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [July 14, 2016, 4:58am UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/17 "2016-07-14T04:58:38Z")
> [@Velocity](#): > > A laser, though, being light, would reach its target pretty much instantaneously. And even if there were some distance in between, the target cannot know that it is being painted by a laser until it is being painted by a laser. Nothing can travel faster than light, and so there is no way for the target to be notified that it’s being hit by a laser until the laser hits. Pretty much instantaneously may be true on planetary combat. But in space? A couple million miles is waving distance. ---
**Author:** ![Grumman](https://avatars.discourse-cdn.com/v4/letter/g/43a26b/32.png) [@Grumman](https://boards.straightdope.com/u/Grumman)\ **Post date:** [July 14, 2016, 4:58am UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/18 "2016-07-14T04:58:46Z")
> [@snfaulkner](#): > > “Captain, incoming torpedoes!” > > “TAKE EVASIVE MANEUVERS!” > > “torpedoes evaded” > > end scene… > kinda boring, eh? And on the other hand, some variant on “All ahead full, and damn the torpedoes!” gets _more_ awesome if it works. ---
**Author:** ![Balance](https://avatars.discourse-cdn.com/v4/letter/b/ccd318/32.png) [@Balance](https://boards.straightdope.com/u/Balance)\ **Post date:** [July 14, 2016, 7:22am UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/19 "2016-07-14T07:22:21Z")
> [@Little\_Nemo](#): > > No, evasive maneuvers really do work. Let’s say you have a weapon that takes thirty seconds from the time it’s launched to the time it arrives at the target. To hit the target, you have to predict where it will be in thirty seconds. That’s pretty easy if the target is traveling in a straight line. But evasive maneuvers are an effective defense. If you’re making a series of constant random course changes, your opponent won’t be able to predict where you’ll be in thirty seconds. With non-tracking weapons that you can see coming, sure. It’s a little harder with FTL torpedoes that track you and light-speed energy beams that you have to hope you can detect via subspace disturbances (otherwise, you can’t know they’ve fired until the beam reaches you), and which are still faster than you, since you engage at sublight. My point was that the computers are not just projecting the other ship’s normal maneuvers; they’re predicting the _computer’s_ evasive maneuvers, based on observed behavior, an expert system loaded with historical info on the enemy, local tactical considerations, and so on. They’re aiming at the spot they expect the other ship to dodge into, hoping to get close enough that the homing torpedoes can make up the difference, or the target can’t dodge the energy beam. Meanwhile, the target is doing…stuff. ECM, only more so. Redirecting shield power. Pulsing the engines to produce warp field distortions that will mislead the targeting computer as to the direction of the next maneuver. Jamming subspace with spurious signals consistent with disruptor fire. Spamming it with network access requests, for all I know. So, for the type of evasive maneuvers you’re talking about–the computer’s already doing that, and more. Or it would be, if it would actually help; I could try to justify the generally mostly static battles in Trek by drawing the conclusion that the computers recognize that the enemy computer is capable of adjusting for most gross maneuvers, and that such maneuvers are therefore a waste of power. The other computer knows that it knows, so they settle down to a slugfest, with most of the complex maneuvering being more subtle–shield tweaking, small course adjustments, and ECM. Until, of course, their organic passengers decide to try to help. > [@Little\_Nemo](#): > > Only if you have a weapon that can track its target and make course changes. A laser beam can’t do that; it just goes where you point it. Hence torpedoes. TOS photon torpedoes seemed pretty inaccurate, but the quick mod Spock and McCoy did on one suggests they have some built-in homing capability; it just doesn’t usually work on cloaked ships. The inaccuracy could be a testament to the effectiveness of ECM; I have posited that the Federation/Klingon war included a major tech race in countermeasures. After the war, there’d be plenty of stuff available that could potentially confuse the relatively dumb torpedo. Of course, it all depends on the level of technology available. I’m mostly talking in Trek terms, because that seems to be what the OP was aiming for. Other settings with a similar level of tech are subject to much the same argument, though, and higher tech mostly pushes it farther. [Schlock Mercenary](http://www.schlockmercenary.com/), for example, has powerful, largely independent full AIs running the ships. The AIs may have meetings, full conversations, literal chess games, call reinforcements, blockade the reinforcements, and many other things…while the captain is still pronouncing the “e” in “evasive”. ---
**Author:** ![Jackmannii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jackmannii/32/311_2.png) [@Jackmannii](https://boards.straightdope.com/u/Jackmannii)\ **Post date:** [July 14, 2016, 1:07pm UTC](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841/20 "2016-07-14T13:07:39Z")
> [@RealityChuck](#): > > In 1915, the liner Lusitania took evasive maneuvers near the coast of the UK. It put them broadside to a German sub, making it an easy target. Didn’t work out I thought the problem was that the Lusitania did **not** zigzag at the critical time. _“What remains inexplicable is why, at 1:45 p.m. on 7 May, Captain Turner decided to turn and hold Lusitania onto a course of 87 degrees east for a steady four-point bearing. This action required 40 minutes of steaming in a straight line, which in a war zone goes against common sense. Had whatever orders Turner received been so unclear that he thought zigzagging was only necessary after danger was sighted? It was more than halfway through these 40 minutes that U-20 fired upon Lusitania, as the ship had not changed her bearings for the previous 25 minutes, making her vulnerable to attack.”_ > **[The Culpability of Captain Turner](https://www.rmslusitania.info/controversies/captain-turner/)** > > Was Captain Turner at fault for the torpedoing of the Lusitania? Firstly, let it be said that Captain Turner was an experienced captain, one of the best in the business.  Cunard would not have entr… As for maritime evasive maneuvers (not routine zigzagging), they seemed to work out well in WWI and WWII when ships were trying to avoid being hit by aerial bombs, especially bombing at high altitude (I recall one description of a ship targeted by a zeppelin that found it relatively easy to evade bomb drops). And the tactic was repeatedly successful in the south Pacific for both sides. Might not be so good in deep space though. :dubious: [Next page](https://boards.straightdope.com/t/orderinng-evasive-maneuvers-a-recipe-for-disaster/759841.md?page=2)