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You may have heard of this common fantasy trope, an archer firing multiple (usually 3) arrows in a single pull of the bow.

Now, I am not an expert at bows or tactics, but it seems to me that the loss of accuracy is not worth even attempting this and that's assuming it could work!

What problems appear with this 'Multi-arrow' bow and how can I overcome these? What are the actual realistic advantages and disadvantages of a multi-arrow bow if it could work?

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  • $\begingroup$ Having tried this before...yeah your assumption is correct. I am no master yeoman but its a dumb idea. $\endgroup$ – James Jan 14 '16 at 6:20
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    $\begingroup$ Not an answer: I am an archer, and have fired two arrows, both nocked next to each other, and they landed next to each other, if this helps at all. It required a lot of patience and bad posture (leveling out the bow a bit to the side so the arrows could rest on it, etc). It was on a modern recurve bow (similar-ish to what you see in movies). $\endgroup$ – Mikey Jan 23 '16 at 3:10
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    $\begingroup$ @Mikey That must have been cool, I wish I could have seen it $\endgroup$ – TrEs-2b Jan 23 '16 at 21:58
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    $\begingroup$ @Mikey, I'm an archer too and can confirm what you say: there is no accuracy or aiming problem (with two arrows, I've never tried more). The arrows fly a near identical path, right next to each other. $\endgroup$ – Jacco Dec 9 '16 at 20:46
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    $\begingroup$ As someone with an invested interest in Ancient warfare, this topic caught my eye so I couldn't resist sharing that there is a very intriguing crosspost from history.stackexchange titled "Are there any historical sources that support the claim that ancient high-speed archers held multiple arrows in their hand?" that might provide further insight into what many perceive is an unrealistic topic, but there is definitely historical basis to this question! The post has $\endgroup$ – SanDiegoBookReview Jan 6 '17 at 2:12
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Your main problem is that you're trying to fling multiple projectiles with a single bowstring. I'm no physics guru, but it seems that you're going to be dividing the pounds of pull across the total number of projectiles -- so you'll get correspondingly less range & target penetration than if you stuck with a single arrow (ignoring more obvious issues like aiming). Someone actually ran the numbers on how much kinetic energy from the bowstring is transferred to the arrow, if you're interested.

A crossbow is a much more workable solution, as the strings can be drawn in advance, and held in place. That leads to the possibility of firing more than one projectile, in quick succession. Such weapons are indeed a trope, usually because the increased firepower is desirable from an action standpoint, but the limitations of the time period will not allow firearms.

One solution to firing multiple arrows is a special crossbow, featured in a battle scene in the 2000 film The Gladiator. On first glance, it looks rather ridiculous, but I actually feel it is a workable design (albeit perhaps not terribly practical for anything other than a showy arena skirmish) for the simple reason that each crossbow bolt has its own string, rather than some sort of imaginary bolt "magazine" that ignores the necessity of re-cocking the string after each firing. Additionally, it dispenses with any sort of fanciful common trigger system, and appears to have the wielder just rotate the entire weapon on its axis.

prop from the film The Gladiator (2000)

A simpler version would be the double-sided crossbow, from the 2000 film Dracula:

prop from the film Dracula (2000)

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    $\begingroup$ actualy rapid fire crossbows where a thing in real history: en.wikipedia.org/wiki/Repeating_crossbow Additionaly: while it is true that each arrow would have less force if you fire multiple from one string this might not be a problem depending on what you shoot at...penetrating a medival plate armor? bad. shooting at unarmored peasants? still more than enough force. $\endgroup$ – m.fuss Jan 6 '17 at 15:12
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    $\begingroup$ Even then, I suspect that you wouldn't be dividing by 2; I suspect that only a fraction of the stored energy in the bow goes into propelling the arrow: specifically, the amount of energy that changes how fast it straightens up, between dry-firing a bow and firing it with an arrow in... which is not a lot. Seems to me, that fraction should rise as you add more mass to push out the way to straighten the bow; the bow might even straighten noticeably slower if firing a hundred arrows. $\endgroup$ – Dewi Morgan Oct 17 '17 at 14:12
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Accuracy

Let me expand on "reduced accuracy". I base this on my own experience shooting target-weight bows and observing others.

Accuracy at any decent range depends on some fairly fine-grained factors. Aim a fraction of an inch high or low, or draw the string back not quite as far as usual (or just a bit farther), and you're probably going to miss your mark. You might still hit a large target somewhere, but it won't be what you were aiming for. It is not uncommon to mark the center-point of the string for this reason, so that you're nocking the arrow at the same position (and thus drawing at the same angle with respect to the bow) each time. The key to good aim is consistency.

If you add arrows to the string in a single draw, then by definition those arrows are not positioned to hit your target. Movies usually depict multiple arrows being spaced an inch or so apart on the string, maybe more. And if those arrows have fletching (feathers), you probably can't get them much closer than half a inch on the string. (For any decently-heavy bow, the arrow itself is about a quarter-inch in diameter.) That's a huge difference when shooting at even 30 yards, to say nothing of 50 or 100 yards. Those extra arrows may look pretty, but they aren't hitting your target. I suppose if you're shooting at a large charging army they might hit somebody else, if you're very lucky, but probably not (see "power").

Power

Other answers have already addressed the reduced power so I won't repeat them. Your arrows aren't going to pack the punch you need to do damage. They're also not all going to get the same amount of power; the one in the middle will have more force than the others, which will likely fall short. (Thanks to XandarTheZenon for pointing this out in a comment.)

Practicality

A competent archer can fire an aimed shot about once every five seconds; good ones are even faster. A lot of this speed comes from the ease of the load-draw-release cycle. It's a very smooth motion; you draw an arrow from the quiver by its nock and place it on the string. You don't even need to be looking at it; this is done by feel. (Instead you're looking at your target.)

Now, how long is it going to take you to load three arrows onto the bowstring? I don't think you can do them all at once, and if you do them one at a time then the ones already on the string are going to slow you down. I haven't tried the experiment, but I'm going to be bold and say that it will take you longer to load and fire your trio of arrows than it would take to fire them individually.

So you can shoot less-accurate under-powered arrows more slowly, or you can shoot them one at a time instead. I know which I'd choose.

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  • $\begingroup$ I think that this sums up what would happen much better than what I said. $\endgroup$ – Xandar The Zenon Jan 14 '16 at 3:12
  • $\begingroup$ @XandarTheZenon your point about the angles is interesting; I'd been assuming three "shelves" on the bow so the arrows would be parallel (though two are not at your draw length), but if you're trying to fire them all off the same shelf, no that's definitely not going to work. Also, sorry, didn't mean to ninja you there -- I hadn't seen your answer before writing mine. $\endgroup$ – Monica Cellio Jan 14 '16 at 3:18
  • $\begingroup$ Don't worry about it, I admire those who can write a one page essay on a random topic and make it neat and sensible. Something I don't think has been addressed here is that the amount of force exerted on an arrow would be less for the bottom and top and more for the middle. The point with the most power would be where you pull back the bow, and then I'm pretty sure the arrows' power would exponentially decrease as you move away from it. After all, there's a reason bows were designed the way they were. For a single arrow in the center. $\endgroup$ – Xandar The Zenon Jan 14 '16 at 3:25
  • $\begingroup$ I proffer my ideas that other my profit from them. I actually enjoy seeing people use my ideas, or people with similar ones. $\endgroup$ – Xandar The Zenon Jan 14 '16 at 3:51
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    $\begingroup$ From my experience as a recurve and longbow archer I can wholly agree with this answer. $\endgroup$ – fgysin Jan 14 '16 at 14:21
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I use a recurve and longbow. Getting good at this took practice, like a lot of practice.

First. There are some very expert opinions out there on why this is fake and or a bad idea but there are some problems with that. Most people aren't thinking of the bow as a weapon of war. They are thinking of it as a hunting/sport weapon. They are thinking of compound and recurve bows where it is pretty much a given that you are going to be using bow hand draw and not arrow hand draw.

Second, the physics around arrow flight are really REALLY complicated. So complicated that for a long time people thought bows were an impossible mechanism leading to the coining of the "archers paradox" now I'm not going to get into the specifics but suffice it to say that the loss of acceleration is correct but not as dramatic nor as important as you'd think in the context of a battle.

third thing is, Arrow hand draw is important which means owning a bow that allows you to do this is important, you can get a longbow, and if you are interested in them I highly reccommend it, or you can just get a recurve for the opposite of your dominant hand and sand the grip to shape it a bit. Professional olympic archers can fire an arrow maybe every once every 3-5 seconds an ancient archer could fire an arrow about once every second. The reason is arrow hand draw lets you rest, nock, and draw the arrow as a single motion rather than maneuvering the clumsy bow hand draw. This is going to help you keep the top arrow from going off course or worse, interfering with the flight of your other arrow.

fourth thing, in sports and hunting accuracy is important, in battle they are important but the MOST important thing is how many arrows you can put down range within a specific amount of time. It may not surprise you to learn that people really don't like getting shot with an arrow, so the less of a break in the screaming bodkin-pointed death missiles there was, the less of an opening you presented. Also the average range for an archer to be shooting at individual targets in battle is 170-200 feet at most otherwise they would just be firing into the mass of people hoping to hit. So you don't actually have to get it that far.

So to pull off the famed "multishot" you need to knock two arrows, I know theres a lot of ways to do that and some people use a mechanism to aid them in having a clean release. I've personally found this is the worst way to do this trick so I would avoid it. The method I've always used is one finger above the nock and two below but for this you are going to make an "arrow sandwich" with one below the first arrow one in the middle and one on top of the second. and you need to grip the bow so that your index (pointer) finger can extend and the tip can rest between the two.

If you did it right both the arrows should be perfectly straight.

Now here's the part that's going to take practice. There are two things i've found that generally make this trick work reliably. First, and most important, once you release the string your index finger needs to slide out from between the arrows, otherwise the hens (the two matching coloured flights) are going to sting it on the way past, your instinct is going to be to curl it back in but what usually happpens when you do that is it deflects the bottom arrow down. The best thing to do is to flick it straight out so it's out of the way, this may deflect the top arrow up a bit but over a longer distance it will drop back down and you should still get a pretty accurate shot. Second, draw the bow with only your middle finger, keep rour ring and index finger extended to stabilize the arrows but you should be pulling from the middle, the reason for this is, while the bow will deliver all of its force across the entire string it delivers the greatest acceleration from the point you drew it back, for maximum accuracy this should be directly between the two arrows.

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Reduced Accuracy

As you mentioned, the accuracy of all of the arrows would be significantly degraded.

Reduced Power

A bow transfers energy from the bent wood/materials of the bow into an arrow through its bowstring. The amount of momentum imparted depends upon a number of factors but by adding multiple arrows to the bow string, you are at the least dividing the momentum by the number of arrows added.

Decreased momentum means:

  1. Lower range
  2. Less penetrating power

Historically Speaking

I suppose the best argument about whether you gain or lose more by adding arrows to the bow string is by looking through history. The trick is an obvious one so if the people who did it greatly benefited from it, you'd expect everyone to be doing it.

Limiting Factors

The limiting factors of arrow acceleration are:

  • The mass to be propelled, for example the arrow(s) - $m_{arrows}$
  • The mass of the limbs of the bow - $m_{limbs}$

Also there's a scaling factor, in that the firing of the bow causes the bowstring (and arrows) to pass through the entire draw length (perhaps 24-30 inches). Meanwhile the limbs of the bow (which are forcing the arrow through that distance) may only pass through a few inches. This distance might be 8-10 inches or so (see image below).

Bow drawn and at rest:
Bow drawn and at rest

Because the ratio of motion between the arrow and bow limbs are not constant you actually get a relatively complex interaction between the two. Initially the force propelling arrow and limbs are high. As the string returns to rest, the amount for force decreases while the amount of motion increases.

Even if you set the arrow mass at zero (no arrow notched), the bow will take time to return to rest state (FYI, never draw and release a bow with no arrow notched, this can break your bow) because the bow limbs have finite mass.

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  • $\begingroup$ I'll have to insert a cautionary note here concerning power. I suspect that stepping up to 3 arrows will not cut arrow speed by a factor of 3, although it will have some effect. Clearly arrow resistance is not the only factor limiting bowstring velocity. If this were true, then firing an arrow with extremely low mass would provide extremely high velocity, and this is not true. $\endgroup$ – WhatRoughBeast Jan 14 '16 at 3:36
  • $\begingroup$ @WhatRoughBeast, the momentum of the bow's arms plays a roll too. Because the bow arms apply the force, the total acceleration/max velocity that can be imparted is limited to speed at which the bow's arms can return to their normal position. Shoot too much mass are you're limited to the acceleration you can apply to the arrow. Shoot too little mass and you're limited to the acceleration of the bow's arms. You get the lesser of the two numbers. $\endgroup$ – Jim2B Jan 14 '16 at 4:55
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Actually, it is quite possible to fire THREE arrows with a single draw. I first saw this technique in the Hindi movie, Bahubali (2), The Conclusion. Google for images and relevant yt clips.

Now, while I'm sure there was liberal application of Movie Magic, especially when the hero shot past the gal's head—two past her ears, one above her crown…I've not been able to figure out how to bump one of the arrows into a higher/wider flight—I've nonetheless been able to duplicate the draw if not the loading speed and fluency.

Note the draw hand's inverted grip with thumb-down, palm-away. Inverting is not necessary, but is definitely a conversation starter on ranges. When the arrows are parallel, their grouping is quite tight. I've yet to get a spread triple hit by putting angles between the shafts.

But instead of me telling y'all about it, I recently found this: https://youtu.be/l6HdEqOpgzE

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  • $\begingroup$ Please don't answer with only a link. Answers should be written in a way that will make them usable even if all links expire. Without seeing a movie or youtube clip, your answer makes no sense now. $\endgroup$ – Mołot Oct 16 '17 at 9:00
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    $\begingroup$ Welcome to Worldbuilding! As the above two comments rightly say, you've answered the question in a youtube video. What the above comments fail to say is that this is actually great as it's a direct demonstration of what the question is looking for as opposed to some explanation with no back-up. However, it would be very useful if you could edit your answer to include the relevant points of the video as well in case the link stops working. Thanks! $\endgroup$ – Mithrandir24601 Oct 16 '17 at 9:56
  • $\begingroup$ I think this looks okay already, but it would definitely be better if you could edit your answer to tell people what can be seen in the video. Not everyone can watch videos every time and we try to give readers all the information necessary directly. Links of all sorts can get outdated, which would leave this answer somewhat lacking. If you have a moment please take the tour and visit the help center to learn more about the site. Have fun Love Robin Miller! $\endgroup$ – Secespitus Oct 16 '17 at 10:28

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