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The discussion so far seems to reinforce the point I made in Case 1, that warbows were insufficient to pierce shields and still threaten the soldier holding the shield. Again, this is the result of the arrows catching in the wood even if they do penetrate.

From the references I've found it appears that metal-prod crossbows, or arbalests, did not appear until the 14th century. As the only accounts we have so far are that it would take a crossbow with three to four times (plus) the draw weight of a warbow to penetrate a Viking shield, we can conclude that the Viking shields were probably entirely sufficient for the threats of that era.

As to the usefullness of a pavise (Case 2). I see reason to doubt their degree of efficacy. I'd like to know how well David Ruff's crossbows penetrate at 100 to 300 yds. I suspect that the pavise only becomes useful against arbalests at longer ranges.

This suggests to me that 15th century warfare may have been similar in some ways to WWI. Specifically battle lines were drawn far enough apart that the missile weapons were of very little use in killing infantry - by forcing them to take cover. And that artillery/cannons were used, along with tanks/knights to break lines.
Artillery...
The word artillery itself derives from "arc tireur" which is not surprising since barrage fire is the most effective use of the bow in massed confrontations at extreme range. IMO a case can be made for the ability to cast a heavy arrow further than your opponent as a primary cause of the need to use a heavier bow, which might be in a tactical sense of at least equal importance as the ability to penetrate many if not all of the available means of defense.
Rod.


Last edited by Rod Parsons on Thu 29 Jun, 2006 9:22 am; edited 1 time in total
[quote="Rod Parsons"]
Jaromír Koz<caron>iak wrote:
Geoff Wood wrote:
Jaromír Koz<caron>iak wrote:


I agree, decorative is a possibility. They are pieces of evidence, to be taken in conjunction with any others we can get hold of. On the decorative suggestion, it does seem a little odd that people of the period would place real metal objects (e.g. swords, spears) in graves, and even the metal parts (e.g. boss) of shields, but decide that the wooden parts were too valuable to bury, so they'd put a decorative thin wooden bit in its place. That seems to suggest wood was more valuable to them than metal?



Where shield furniture is found in burials, such as Sutton Hoo, the metal furniture was not placed separately in the grave, rather the shield was buried intact but the wood did not survive, leaving the metal components to be found in situ.
Rod.


Hi Rod
I wasn't meaning to imply otherwise. The metal shield parts I was referring to above were attached to the (hypothetically decorative) wood, which, in a sense, makes the use of decorative shields even odder, since one would have to go to the trouble of taking the metal parts off the (again hypothetical) thicker 'real' wooden shield and then attach them to the (hypothetical) thinner decorative shield. As Jaromir has said, odd things happen in funerary rites, so it may have happened. I'm just expressing an opinion that it appears, shall we say, so perverse as to be unlikely. I'm sorry if the incomplete nature of my earlier post made my meaning unclear.
Regars
Geoff
Quote:
If full power bows were being used the fight should have been a lot easier for the Normans I would think ?


Why? In various battles, lightly armoured Scottish infantry managed to continue fighting even after being hit by English arrows. Especially since we don't know how many archers William had at Hastings...

Quote:
At least in North America many Indian tribes used self bows shorter and less powerful than maximum power warbows.


And some used very powerful bows, at least if de la Vega is to be believed. He wrote that the none of the Spaniards in an early trip into Florida could draw the bows the Amerindians used. He also gave many accounts of the power of these bows.

By the way, if an arrow would pierce one of these rather thin shields, what would a pike or couched lance do to one?
Matuls from Poland makes interesting pavises, tey're made from approx. 10 mm bent plywood, several layers of linen, glued with with special mixture described by Monk Teofil, made from raw leather and bones. If you click on image of pavise, new page will open with images of his shield being shot at: "Here you can see effects of shooting to pavise. I used 20kg bow from 30 meters. " - Although poundage seems very small.

I imagine that layers of glued linen or leather could greatly improve the protective ability of shield - they would prevent the wood splitting too easily, and they could add a lot of friction by applying force to the arrow shaft, because penetrated cloth or leather would try to close the gap.

http://www.matuls.pl/english/shields.html

[ Linked Image ]
I'm no expert but here it goes....

Most archers didn't shoot straight at their target. A volley was used shooting up to rain down on the enemy instead of a straight shot. The arrow leaving the warbow could reach a very high velocity because of the force of the bow. However, when it reaches the peak of it's arch and begins to descend the arrow cannot exceed it's terminal velocity which may be less than the velocity of the arrow when it immediately leaves the bow. Therefore any bow above a certain poundage (whatever is needed to let the arrow reach terminal velocity on its descent) would have the same power of a bow that has an even higher poundage. The only difference would be that the heavier bow has more range. When an arrow is shot in an arch it can only impact at terminal velocity so this impact may be lighter than modern tests when a bow is shot straight at the shield.

Did that make sense to anyone else....?

(if i am wrong please correct me, i would hate to give out false info)

BTW this is about warbows only, because i believe crossbows were shot directly at targets(?).

-James
J. Bedell wrote:
Therefore any bow above a certain poundage (whatever is needed to let the arrow reach terminal velocity on its descent) would have the same power of a bow that has an even higher poundage. The only difference would be that the heavier bow has more range.

I believe that this was the primary intent of the English archer: to fire the heaviest arrows possible - as far as possible - as quickly as possible. The purpose of these monster bows was not to increase armour piercing capability but to give heavy arrows a decent range on the battlefield
J. Bedell wrote:
I'm no expert but here it goes....

Most archers didn't shoot straight at their target. A volley was used shooting up to rain down on the enemy instead of a straight shot. The arrow leaving the warbow could reach a very high velocity because of the force of the bow. However, when it reaches the peak of it's arch and begins to descend the arrow cannot exceed it's terminal velocity which may be less than the velocity of the arrow when it immediately leaves the bow. Therefore any bow above a certain poundage (whatever is needed to let the arrow reach terminal velocity on its descent) would have the same power of a bow that has an even higher poundage. The only difference would be that the heavier bow has more range. When an arrow is shot in an arch it can only impact at terminal velocity so this impact may be lighter than modern tests when a bow is shot straight at the shield.

Did that make sense to anyone else....?

(if i am wrong please correct me, i would hate to give out false info)

BTW this is about warbows only, because i believe crossbows were shot directly at targets(?).

-James


Makes sense to me and would probably give the shields better odds of stopping arrows moving at about the same speed no matter how strong the bow. Still use at closer range might still occur and then extra power might make a difference.

Also when an arrow is going up or going back down at the end of it's arc it is always loosing speed to drag. When coming down the arrow is accelerating but still not as fast at impact if there was no drag, so the arrow gets as high as it can get and then regains speed but never gets to be as fast as it was a few feet away from the bow.
Jean Thibodeau wrote:
Also when an arrow is going up or going back down at the end of it's arc it is always loosing speed to drag. When coming down the arrow is accelerating but still not as fast at impact if there was no drag, so the arrow gets as high as it can get and then regains speed but never gets to be as fast as it was a few feet away from the bow.


IIRC Hardy reckons that his arrows retained about 75% of their energy at the end of the arc.
Dan Howard wrote:
Jean Thibodeau wrote:
Also when an arrow is going up or going back down at the end of it's arc it is always loosing speed to drag. When coming down the arrow is accelerating but still not as fast at impact if there was no drag, so the arrow gets as high as it can get and then regains speed but never gets to be as fast as it was a few feet away from the bow.


IIRC Hardy reckons that his arrows retained about 75% of their energy at the end of the arc.


An arrow from a heavier bow might get higher before it ran out of steam and thus have more potential energy to gain back on the way down, but the main advantage would probably be more range. The exact math is beyond my knowledge but 75% sounds believable to me. :D I let some physics or math person figure it out. ;)
I think armour penetration was a significant factor in bow development. The only reason to use heavier arrows is to achieve better penetration; there is no other benefit from launching a heavy arrow. Heavy crossbows, do to the nature of their construction, cannot launch light arrows at any great velocities. If range was the only issue then a lighter crossbow shooting a lighter arrow would be sufficient to out perform any heavy draw steel crossbow.

Both crossbowmen and longbowmen have to arch their shots into their target because of the relatively low velocities that crossbows and longbows lob their arrows/bolts. When shot at a completely flat trajectory a longbow or a crossbow will achieve a range below 50 meters. This is because all of the arrows velocity is being used to propel the arrow forward and none of it is being used to keep it in the air. Essentially the arrow launched from a direct shot will hit the ground at the same time as an arrow that was simply dropped from the bow. When an arrow is launched at an angle, say 45 degrees, then a portion of that arrows energy is being used to keep the arrow in flight. When launched at 45 degrees an arrow will use half its energy to fight gravity and keep the arrow in the air while half will be used to propel the arrow forward. The actual angle which the arrow hits its target is decided entirely by that targets range from the archer. At short ranges the archer will have to shoot at fairly flat trajectories in order to hit the target. At long ranges the archer will have to aim high in order to give his arrow enough range to hit the target. There is nothing arbitrary about the chosen trajectory, if an archer aims to high his arrow will land behind the target and if he aims to low it will land in the dirt in front of his target. The only exception to this is of course if an archer aims at angles above 45 degrees, but I haven’t heard of any one who can aim like that and I can think of no reason why any one would want to try aiming like that.

This same rule applies to modern day rifles and cannons as well as old timely muskets. With modern day rifles you have to adjust the sight according to the targets range in order to lob the bullet into the target. The only difference being that modern day guns shoot bullets up to 15 times faster than any crossbow or longbow, so the angles are smaller than with a bow.

When an arrow is fired at long range its velocity is not limited by its terminal velocity. The terminal velocity of an object is simply the velocity it obtains when the acceleration exerted on it by air resistance equals the acceleration exerted on it by gravity. An arrow on the other hand has an initial velocity imparted on it by the bow. The only way a bow would be limited by its terminal velocity is if it was fired at a 90 degree angle directly up into the sky. When an arrow is fired at 45 degrees it uses half its velocity to propel it upwards and half its velocity to propel it forwards. Only the vertical portion of the velocity will be affected by the arrows terminal velocity. The arrow of course will lose a portion of its velocity to air resistance, even when striking a target at maximum range, the power of the bow will ultimately decide its impact power.
Carl Scholer wrote:
There is nothing arbitrary about the chosen trajectory, if an archer aims to high his arrow will land behind the target and if he aims to low it will land in the dirt in front of his target. The only exception to this is of course if an archer aims at angles above 45 degrees, but I haven’t heard of any one who can aim like that and I can think of no reason why any one would want to try aiming like that.


This kind of shooting seems to have been important in English longbow tactics - important enough to be practiced during competitions. There was a specific archery contest in which the idea was to fire an arrow up into the air and have it land on a target spread out on the ground. Unlike other archery contests, you actually move CLOSER to the target as the level of difficulty increases.
Dan Howard wrote:
Carl Scholer wrote:
There is nothing arbitrary about the chosen trajectory, if an archer aims to high his arrow will land behind the target and if he aims to low it will land in the dirt in front of his target. The only exception to this is of course if an archer aims at angles above 45 degrees, but I haven’t heard of any one who can aim like that and I can think of no reason why any one would want to try aiming like that.


This kind of shooting seems to have been important in English longbow tactics - important enough to be practiced during competitions. There was a specific archery contest in which the idea was to fire an arrow up into the air and have it land on a target spread out on the ground. Unlike other archery contests, you actually move CLOSER to the target as the level of difficulty increases.


Sort of a mortar type trajectory and at a very high angle you could rain down arrows at a massed target that could be very close. At close ranges you could have half your archers shooting at a high angle and half in direct fire: The targeted shield wall, for example, would have the problem of deciding to use their shields to protect their front or from arrows coming almost strait down. Timing your fire could also be used as the arrows shot strait up would take longer to get to the target, so out of 12 arrows maybe the first 8 to 10 could be fired at a high angle by all the archers and the last few fired strait at the targets timed for close to simultaneous arrival of some of the arrows. Switching from one to the other should be very annoying to the targets and increase the odds of slipping between shields.

Carl: Thanks for explaining it better than I did. :cool: Mostly what I got mostly wrong is that at the top of the arc the arrow hasn't stalled to zero speed at 45° angle. ( That would only happen strait up. )
Re: Retained velocity
Currently Mark Stretton and Pip Bickerstaffe are using a radar gun to measure retained velocity shooting a heavy shaft out of the heavy bow.
There are still doubts about the degree of efficacy against hardened plate of some thickness, but these shafts are indisputably lethal against a soft target at any range.
But this is balanced by the probable range of qualities of defence to be encountered on the battlefield, the variations in thickness and ductility on a given suit of plate and other factors.

Much work remains to be done studying the effectiveness against hardened armour, but to test a pavise as shown above, with a draw weight of 20kg is meaningless within the context of war shaft performance.
20kg (44lb) is a draw weight more appropriate to a weak target archer and is insufficient even to obtain a worthwhile mark at 100 yards with a light arrow.

Any significant penetration test should be with a bow in the 120lb to 150lb median range for warbows (though it would be interesting to compare extremes of 90 lb and 175 lb or more), a shaft of 3 oz (1310 grains or a little less for a flighting/distance war shaft) to 4 oz (1750 grains or more for a heavy war shaft) and the point should be of appropriate geometry for the type of target and at the very least case hardened.

On the subject of war bow weights in general, it seems likely that war bow weights developed over time from the hunting bow, following the need to satisfy two main criteria.
These are the ability to outrange your opponent and the need to penetrate his defensive gear.
These two criteria create a contradiction, in that a compromise needs to be made unless shafts become specialised, since penetration requires a heavier shaft and distance requires a lighter shaft.

But this is why a "light" flighting war shaft so far outweighs most heavy hunting shafts, since hunting is essentially a close range affair with the bow, due to the relatively low velocity of the projectile at around 150 fps.
An ethical hunting distance is determined by the greatest distance at which the ability of game to jump the string is greatly reduced, and in practical terms this means that 30 paces is in this context a long distance and 10 to 15 paces probably ideal with a bow speed of around 165 fps, a shaft of adequate weight (600 to 1000 grains) and a relatively high anchor point which shortens the point on distance.

In warfare with a heavy bow, your point on distance is well in excess of this, particularly with a lower anchor, and a hunting distance is inside the comfort zone and probably past time to start thinking about dropping your bow and going to hand strokes.
Rod.
Dan Howard wrote:
Jean Thibodeau wrote:
Also when an arrow is going up or going back down at the end of it's arc it is always loosing speed to drag. When coming down the arrow is accelerating but still not as fast at impact if there was no drag, so the arrow gets as high as it can get and then regains speed but never gets to be as fast as it was a few feet away from the bow.


IIRC Hardy reckons that his arrows retained about 75% of their energy at the end of the arc.



There were some tests run on myth busters (yeah ok not period) onto the myth if a bullet could kill if fired into the air and it came down on someone.

The terminal velocity was not enough of ANY bullet they fired to kill - however what they found (to the point of this thread) is that it is near impossible to fire a bullet straight up so that it goes up, stops and then falls to earth - thus hitting terminal volicty. Rather a bullet traveling in an arc retains its energy.

Same thing with arrows - an arrow fired at an arc - say in a volley will retain its energy, Dan is correct and i believe hardy is correct is saying that energy is retained. i'm not sure i buy 75%, but its gonna pack a punch when it hits.



david
Re: Retained velocity
Rod Parsons wrote:
Currently Mark Stretton and Pip Bickerstaffe are using a radar gun to measure retained velocity shooting a heavy shaft out of the heavy bow.
There are still doubts about the degree of efficacy against hardened plate of some thickness, but these shafts are indisputably lethal against a soft target at any range.
But this is balanced by the probable range of qualities of defence to be encountered on the battlefield, the variations in thickness and ductility on a given suit of plate and other factors.

Much work remains to be done studying the effectiveness against hardened armour, but to test a pavise as shown above, with a draw weight of 20kg is meaningless within the context of war shaft performance.
20kg (44lb) is a draw weight more appropriate to a weak target archer and is insufficient even to obtain a worthwhile mark at 100 yards with a light arrow.

Any significant penetration test should be with a bow in the 120lb to 150lb median range for warbows (though it would be interesting to compare extremes of 90 lb and 175 lb or more), a shaft of 3 oz (1310 grains or a little less for a flighting/distance war shaft) to 4 oz (1750 grains or more for a heavy war shaft) and the point should be of appropriate geometry for the type of target and at the very least case hardened.

On the subject of war bow weights in general, it seems likely that war bow weights developed over time from the hunting bow, following the need to satisfy two main criteria.
These are the ability to outrange your opponent and the need to penetrate his defensive gear.
These two criteria create a contradiction, in that a compromise needs to be made unless shafts become specialised, since penetration requires a heavier shaft and distance requires a lighter shaft.

But this is why a "light" flighting war shaft so far outweighs most heavy hunting shafts, since hunting is essentially a close range affair with the bow, due to the relatively low velocity of the projectile at around 150 fps.
An ethical hunting distance is determined by the greatest distance at which the ability of game to jump the string is greatly reduced, and in practical terms this means that 30 paces is in this context a long distance and 10 to 15 paces probably ideal with a bow speed of around 165 fps, a shaft of adequate weight (600 to 1000 grains) and a relatively high anchor point which shortens the point on distance.

In warfare with a heavy bow, your point on distance is well in excess of this, particularly with a lower anchor, and a hunting distance is inside the comfort zone and probably past time to start thinking about dropping your bow and going to hand strokes.
Rod.



We can test 90, 107 and 127lb bows against sheilds and pavices, anything heavier - get another shooter. Can anyone get me an exact makeup of the thickness to be fired at? At what ranges? and what makeup of the sheild or pavice ei, wood, leather, steel?

I will have to find a range to test beyond 100 yards, but i to would love to see what a heavy crossbow would do at 100, 200 and 300 yards. Gives me an excuse to go shoot.


David
One instance where you would see a lot of short range, direct fire with bows would be naval battles; In the norwegian Leidang (ship levy) laws, it is stated that there shall be a bow for every second seat; A typical ship would have about 20 seats. In addition, many would have their own bows.
Shields are listed as the most usefull piece of equipment in ship to ship combat, and as such must have been effective at least to some degree.
[quote="David Ruff"][quote="Dan Howard"]
Jean Thibodeau wrote:

The terminal velocity was not enough of ANY bullet they fired to kill - however what they found (to the point of this thread) is that it is near impossible to fire a bullet straight up so that it goes up, stops and then falls to earth - thus hitting terminal volicty. Rather a bullet traveling in an arc retains its energy.

Same thing with arrows - an arrow fired at an arc - say in a volley will retain its energy, Dan is correct and i believe hardy is correct is saying that energy is retained. i'm not sure i buy 75%, but its gonna pack a punch when it hits.

david


The essential difference between a bullet and a war shaft when it comes to losing velocity and dropping in is that the shaft is much heavier and is tipped with a hardened sharp point.
Occasionally archers have been know to fire near to the vertical and then be faced with the problem of which way to run to avoid injury.
I for one would not wish to have a heavy war shaft drop on my unprotected head, it could be fatal and only an incurable optimist would assume otherwise.
But the cure might be sudden if unexpected. :-)
I don't know that much about bullets, but I would be far more phlegmatic about a similar scenario with a bullet of moderate caliber.
Rod.
Quick math:

Terminal velocity of an arrow is in excess of the speed of sound. So it's not relevant to the discussion (unless we suppose an arrow traveling in excess of 1000 fps).

There are no contemporary accounts of sonic booms! :D
Steven H wrote:
Quick math:

Terminal velocity of an arrow is in excess of the speed of sound.


How did you arrive at this conclusion? :-)
Rod.
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