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The effects of missiles - how important were armour and shields?

Started by Erpingham, November 16, 2013, 09:12:29 AM

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Erpingham

As promised, some Saxton Pope quotes from his book Hunting with the Bow and Arrow  Not quite as scientific as the technical appendices of Strickland and Hardy but an interesting example of early tests.  The power of the bow quoted is a long way less than the alleged 80J needed to kill people, though it should be noted that it kills a variety of animals throughout the book  :)  I suspect Pope's simple method is not giving a correct measure of the impact energy.


A light arrow from a heavy bow, say a sixty-five pound yew bow, travels
at an initial velocity of one hundred and fifty feet per second, as
determined by a stopwatch.

Shooting at one hundred yards, such an arrow is discharged at an angle
of eight degrees, and describes a parabola twelve to fifteen feet high
at its crest. Its time in transit is of approximately two and one-fifth
seconds.

Shooting straight up, such an arrow goes about three hundred and fifty
feet high, and requires eight seconds for the round trip. This test was
made by shooting arrows over very tall sequoia trees, of known height.

The striking force of a one-ounce arrow shot from a seventy-five pound
bow at ten yards, is twenty-five foot pounds. This test is made by
shooting at a cake of paraffin and comparing the penetration with that
made by falling weights. Such a striking force is, of course,
insignificant when compared with that of a modern bullet, viz., three
thousand foot pounds. Yet the damage done by an arrow armed with a
sharp steel broad-head is often greater than that done by a bullet, as
we shall see later on.

Shooting a blunt arrow from a seventy-five pound bow at a white pine
board an inch thick, the shaft will often go completely through it. A
broad hunting head will penetrate two or three inches, then bind. But
the broad-head will go through animal tissue better, even cutting bones
in two; in fact, such an arrow will go completely through any animal
but a pachyderm.

To test a steel bodkin pointed arrow such as was used at the battle of
Cressy, I borrowed a shirt of chain armor from the Museum, a beautiful
specimen made in Damascus in the 15th Century. It weighed twenty-five
pounds and was in perfect condition. One of the attendants in the
Museum offered to put it on and allow me to shoot at him. Fortunately,
I declined his proffered services and put it on a wooden box, padded
with burlap to represent clothing.

Indoors at a distance of seven yards, I discharged an arrow at it with
such force that sparks flew from the links of steel as from a forge.
The bodkin point and shaft went through the thickest portion of the
back, penetrated an inch of wood and bulged out the opposite side of
the armor shirt. The attendant turned a pale green. An arrow of this
type can be shot about two hundred yards, and would be deadly up to the
full limit of its flight.

aligern

let's just shoot holes in a 15th century mailshirt?
Wow, that's as non PC as you get.
Roy

Erpingham

Quote from: aligern on November 29, 2013, 06:08:03 PM
let's just shoot holes in a 15th century mailshirt?
Wow, that's as non PC as you get.
Roy

Different times, different mores  :)

I loved the assistant's offer - Health and what?


Jim Webster

Quote from: Erpingham on November 29, 2013, 07:01:24 PM
Quote from: aligern on November 29, 2013, 06:08:03 PM
let's just shoot holes in a 15th century mailshirt?
Wow, that's as non PC as you get.
Roy

Different times, different mores  :)

I loved the assistant's offer - Health and what?

yes, I liked that bit as well, especially his reaction to seeing the effect :-)

Jim

Patrick Waterson

The "deadly up to the full limit of its flight" bit is also useful to know for calculating effects.

Thanks for that extract, Anthony: it gives us a bit more knowledge to work with.
"Men occasionally stumble over the truth, but most of them pick themselves up and hurry off as if nothing had happened." - Winston Churchill

Nick Harbud

Do I take it that we are now entertaining the notion that the 3-ply plywood scutum (5-6mm thick) was perhaps not the complete protection against missiles that sundry ancient authors might have led us to believe?
Nick Harbud

Erpingham

Quote from: NickHarbud on November 30, 2013, 04:09:05 AM
Do I take it that we are now entertaining the notion that the 3-ply plywood scutum (5-6mm thick) was perhaps not the complete protection against missiles that sundry ancient authors might have led us to believe?

Pope's tests probably tell us more about thicker wooden shields like an aspis or board shields from Gauls to the Middle Ages.  Plywood is a strange material, which can be harder to split than board (all that cross lamination).  Also, Pope's board had no leather cover.  Once you are talking of a protective system made of layers of different materials, things become more complex.  However, we should also note Pope conducts these tests at short range and that a barbed arrow head would reduce the penetration (it binds, I presume because of the greater effort needed to push a larger surface area of arrow through).

Erpingham

Quote from: Patrick Waterson on November 29, 2013, 10:48:02 PM
The "deadly up to the full limit of its flight" bit is also useful to know for calculating effects.

Thanks for that extract, Anthony: it gives us a bit more knowledge to work with.

Pope is of course speculating (although he probably could have got a museum assistant to help him test  :) ).  Most of his shooting against live targets was at around 60-85 yds, so he doesn't know his 200yds shots would have been effective.  In favour of his speculation, though, is that he was a surgeon, so his anatomical understanding was pretty good.  Incidentally, his findings are backed by what medieval English evidence we have of murders and accidental shootings.  Hunting arrows caused massive wound trauma and haemorage and people were killed accidentally at long ranges by people practicing (there is one sad case where a man goes out to test how far his bow will shoot with his friend.  He stations the friend at the far end of the field to mark where the arrow falls - you can guess the rest)

Patrick Waterson

Aye. *removes hat and stands silent for a moment*

From a kinetic energy point of view an arrow shot skywards is subject to the 'what goes up must come down' rule otherwise known as the law of potential energy.  At the mid-point of a parabolic or hyperbolic curve the energy imparted by the shooter and his equipment has been converted, albeit with less than 100% efficiency, to potential energy, which then converts to momentum on the way down and impact upon arrival.

Quote from: NickHarbud on November 30, 2013, 04:09:05 AM
Do I take it that we are now entertaining the notion that the 3-ply plywood scutum (5-6mm thick) was perhaps not the complete protection against missiles that sundry ancient authors might have led us to believe?


It was excellent protection against arrows, as Centurion Scaeva's experiences, or at least shield-marks, at Dyrrhachium suggest (Caesar, Civil War III.53).  A heavy missile like a pilum or spiculum or any of the narrow-shafted, point-headed, weight-enhanced close-range throwing weapon fraternity could go right through it and possibly into the man beyond unless he was wearing lorica segmentata (the classic hooped armour) rather than lorica hamata (basically chainmail).  If you saw one coming, you tried to dodge it or get your boss* in the way as the metal would stop or deflect the point.  Carduchian arrows might have performed similarly, but I do not think anyone ever got the chance to try.

*Shield boss, not the Society President!  ;)



"Men occasionally stumble over the truth, but most of them pick themselves up and hurry off as if nothing had happened." - Winston Churchill

Erpingham

The other article I mentioned was :

The Longbow-Crossbow Shootout at Crecy (1346) Has the Rate of Fire Commonplace been Overrated? - Russell Mitchell, Dallas County Community College in The Hundred Years War (Part II) Different Vistas Edited by L.J. Andrew Villalon and Donald J. Kagay



As promised I have reread this to see what it can add to our discussions.  Unfortunately, it's arguments, though involving a bit of geometry to estimate target areas, are laid out in a narrative I can't easily extract info from :(  Add to this that I think some of his arguments are wrong, or incomplete, I don't think I'll try.

Essentially though, Mitchell emphasises that the English used plunging fire against the Genoese, which meant they were shooting at an area target.  He calculates the equivalent horizontal target for archers shooting at 45 degrees at a suggested formation of 300 man frontage and 20 ranks deep is 600ft by 90ft.  This is like "hitting the side of a city block" and he doubts even a moderate archer could fail to do this.  (This is one of those areas where his argument doesn't quite work IMO - the 300 x20 formation are supposed to be Genoese and I cannot see them drawing up so deep, as they are there to shoot not to provide target practice).   He is on less secure ground in trying to work out how many arrows would hit something and I don't think he makes any solid case.  He does have a digression on kettle helmets and their effectiveness against plunging shots (good, because they protect head and a lot of the shoulder) and estimates a crossbowman sheltering behind a pavise wearing a kettle hat is 90% protected.

Patrick Waterson

#70
Twenty ranks deep for the Genoese does seem a bit surprising: does he assume they used some form of foot 'caracole'?

[Edit:] Just adding a few thoughts following a quick perusal of Lt Col Burne's account of Crecy.  A deep formation, or at least disposition, for the Genoese might be suggested by the following:

1) The undisciplined French arrival.  While King Philip was discussing with his officers whether to engage or make camp and fight on the morrow, the French knights seem to have taken matters into their own hands and pushed ahead - pushing the Genoese before them.  The Genoese apparently halted, or attempted to halt, three times during their advance, suggesting they were trying to improve their deployment (or even to deploy) but were urged on by the impatient French knights.

2) The Genoese are described as loosing shots as they came, which is consistent with a deep caracole-type tactical formation although it does not necessarily require one.  (Wet crossbow strings may explain why all these shots are noted as falling short, even at c.150 yards.)

3) The English cannon appear to have done considerable execution, or at least had considerable effect, on the Genoese.  While the novelty effect of battlefield artillery would anyway have considerable impact, the material effects would be more pronounced against a deeper formation.

4) When the Genoese faltered, Alencon and his men rode them down but other contingents en route to the English lines apparently bypassed the fracas.

There might thus be something in Mitchell's suggested 300x20 deployment, although I suspect it would have been mainly involuntary on the part of the Genoese! [/Edit]
"Men occasionally stumble over the truth, but most of them pick themselves up and hurry off as if nothing had happened." - Winston Churchill

Dave Beatty

Quote from: NickHarbud on November 25, 2013, 04:10:29 PM

I guess you are using a compound bow to achieve 280-310fps?
Yes, we use modern hunting bows - examples here: http://www.cabelas.com/product/Hunting/Archery/Bows/Compound-Bows|/

I also hasten to mention that our arrows are much lighter than discussed in ancient/medieval sources as we go for penetration of skin with the intent to cut arteries.  We strive for complete penetration which is easily achieved at 40 yards.  This means the arrow goes completely through the animal.  This allows maximum tissue damage and a clean entry and exit wound allowing double the blood flow to assist in tracking.  Along that line, it is rare to drop an animal on the spot with any weapon (bow or rifle) - it will normally run some distance usually related to how close to the heart the shot landed. 

Which morphs into yet another random thought - perhaps an intent of ancient missile weapons was more to stun the target by weight of impact rather than kill outright.

Dave

aligern

likely the intent of the missile weapons is to degrade the opponent's fighting capability . Thus Benkin the Fleming who shot arrows with such force that men who were not pierced were knocked down and bruised by the impact of his shafts did not have to wound or kill to drive off attackers.  So, if enough arrows or slingstones hit hard enough to disrupt the opponent and render him less capable of defending himself then the job is done.
Persian archers quite likely formed deep and sent massed showers of arrows at their opponents. the Greeks learned to run at them so that the bows could not hold them in their killing zone (I think that. this was covered earlier) . Perhaps this was done by the Greek  commanders ordering  a change of pace at each volley and, as Nick pointed out, a fast moving opponent, rather than a static one, considerably reduces the number of volleys that can be delivered. The other difference for the Persians, of course, is that once the Greeks reach them the Persians are far inferior to the Greeks at hand to hand. French knights reaching an English line have to deal with English knights whom missiles have not degraded.
Skirmishers whether with javelins, slings or bows must deliver a lot less fire per yard of frontage than massed bowmen and thus would take. a long time to wear down an opponent. At Pylos the Athenians had plenty of time to degrade the Spartans to the point where they would not  take on Athenian hoplites. However, in the normal course of battle, the skirmishers do their bit and then the battle lines close. that probably does not allow time for their kills to be conclusive, but enough, if one side wins the skirmish battle, to give their heavy troops an advantage, or at least not the disadvantage of being forced to take casualties from opposing skirmishers without reply.

Roy

Erpingham

A few more thoughts on Genoese crossbow tactics

1. Mitchell formation is odd in that he gives each crossbowman on 2ft frontage to operate in.  I doubt you can effectively operate in that width and you certainly couldn't "fire by induction".  Other than men passing loaded weapons like a bucket train this formation would be fairly useless.

2. He chooses to accept 6,000 Genoese - many others would say fewer, possibly as few a 2,000.

3. There is an assumption that these Genoese were all crossbowmen.  Unlikely, as Italian tactics of the time (and many others too) was to accompany the crossbowmen with pavise bearers.  David Nicolle reckons a ratio of 3 or 4 crossbows to a shield bearer.  The fact that the pavises had become separated from the crossbow unit (in the baggage) may mean these men weren't on the field or it maybe they supported their comrades with just their spears.   For an impression of what a 14th century Italian crossbow unit looked like, http://warfare.atwebpages.com/Italy/Sinalunga-DetailLeft.htm
This looks fairly dense but is on its approach march, not deployed to shoot. (a better colour image here http://scoprendoasinalunga.files.wordpress.com/2013/02/7749182518_0f56f64c7d_k.jpeg  - you get the whole thing and it is zoomable) 

4. My best interpretation of the Genoese as described by Froissart is that they are trying to shake out of march order as they funnel onto the field.  They keep moving in order to make space for themselves - it is a narrow entrance to the field, probably at an angle to the English, so they are moving forward, lengthening their line and probably coming round more parallel to bring their full firepower into action.  The shouting is fairly standard - to signal an advance the commander advanced his banner, and shouted the war cry (maybe San Georgio for Genoese - very confusing as the English were shouting Saint George) - the war cry was taken up along the line and they advanced.  They may have shot each time to test the range and the English firecontrol, they may have shot only once.  The English, judging their distance, held fire until the crossbowmen were in range, stepped forward (by order or signal) and delivered a volley.  They probably followed this with more shooting but we can't say whether this was shot in volleys, by contingents or by individuals shooting at will.

5. It is difficult to see Philip ordering his cavalry to "kill the cowards" - even if he could see what was going on, was their time to send an order?  Or was his lead division forced to cut down the fugitives to get into position to charge and the order was a later excuse?  Remember, this story was not told against Philip - he was supposedly being a decisive leader, keen to engage the foe - so could be put in later to rescue parts of his tattered reputation. 


Patrick Waterson

Was it not Alencon and his retinue who were the chief culprits in firstly chaperoning the Genoese ahead before they could properly deploy and then riding them down when they showed reluctance to advance into a shower of clothyard shafts and the roar of the odd cannon?  My impression is that Philip was near the rear of his army and trying to get it to encamp when certain of his subordinates took matters into their own hands ("What do we want?  Action!  When do we want it?  Now!").  One is reluctant to ascribe to him the kind of 20th/21st century cynicism that would see wiping out his own mercenaries on the battlefield as a way of reducing his campaign expenses!

Mention of 'San Giorgio' as the probable Genoese war cry might put a new complexion on the way the French laid into them - what does a knight think when the mercenaries on his side take up the enemy's battle-cry?  A good observation, and one which perhaps deserves more examination as a possible contributor to French conduct on the day, assuming some French contingents were unfamiliar with customary Genoese war shouts.

If Mitchell wants to limit his crossbowmen to 2' apiece that would indeed rather preclude any movement except of crossbows being passed forward to be shot and back to be reloaded (not easy if the men are advancing at the same time).  One question that does arise seeing the crossbow unit at Sinalunga with pavisers fronting it is what all those back ranks of crossbowmen expected to do - did they shoot indirectly, Swedish-style, or would they each advance to the front, peer over/round the pavise, let go a shot and drop back to reload or would they stay as they were with the best shot discharging weapon after weapon and the rest reloading and passing them along?

"Men occasionally stumble over the truth, but most of them pick themselves up and hurry off as if nothing had happened." - Winston Churchill