Wikipedia:Reference desk/Archives/Science/2018 December 30

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December 30[edit]

Like a speeding arrow?[edit]

We all know that the English longbow is the ultimate weapon of all time, the Gatling gun of its age, and that a well-aimed bodkin arrow can easily pierce mail and plate at any range. Indeed, El Alamein would probably have been decided in hours had the English only thought about using their longbows against German tanks. However, when watching the Battle of the Bastards episode of Game of Thrones, I was wondering how plausible Ramsey's shot at Rickon was. Of course, he had plot on his side. But, having shot (weak and inferior modern) bows, I noticed that arrows have a significant flight time - as kids, shooting straight up, we had plenty of time to step out of the way of the arrow before it came down. This would make it basically impossible to aim at an erratically moving target at any but quite short distances. So if the intrepid English longbow men loose a volley of irresistible feathered death against the quivering French in their useless armour, how long exactly does it take for the arrow to cross, say, 100 or 200 yards (or meters ;-), and wreak havoc? --Stephan Schulz (talk) 12:50, 30 December 2018 (UTC)[reply]

Initial speed is roughly 100 meters per second. But you need to pull back hard enough to lift like 150 pounds without the help of multiple pulleys. Sagittarian Milky Way (talk) 13:42, 30 December 2018 (UTC)[reply]
Kids shooting arrows straight up, confident that two seconds is long enough to get out of the way. What could possibly go wrong? Well, Daddy might accidentally run over the bow with his SUV three or four times while backing out of the garage, then replace it with a puppy... Wnt (talk) 14:28, 30 December 2018 (UTC)[reply]
I'm too old for daddy to have had an SUV. And while I agree in principle that replacing an SUV with a puppy is a good idea, I don't quite see the motivation here - do you think driving over the bow might damage the vehicle that much? --Stephan Schulz (talk) 15:31, 30 December 2018 (UTC)[reply]
Arrows shot straight up at a papingo slow right down before falling again, the archers keep out of the area the arrow's expected to land but also watch it in case they do have to get out of the way of a stray shot. Blunt tips these days, but still rather dangerous. . . dave souza, talk 17:18, 30 December 2018 (UTC)[reply]
  • Arrows don't speed, agreed. In the timescale of GoT (i.e. the period of European history which its technology most closely resembles) the arrow had become regarded as a bulk weapon, where many archers would engage with large attacking forces as a form of attrition, and also as an area-denial weapon. They didn't go through plate armour (your ability to fire off plate-piercing bodkins is much less than when firing lighter arrows and a lighter pull), but they stopped the archers being rushed by a horde of angry grunts.
Where a single arrow was intended as a means of assassination, then that arrow had become a crossbow bolt instead. Their greater draw weight gave them a higher velocity and a flatter trajectory, giving better aim, much better aim in crosswinds, and also a faster flight (as mentioned here). This was one of the reasons why the medieval crossbow was regarded so badly at times, with its users being regarded as somewhere between pirates and war criminals. Their disadvantage was their slow rate of fire, compared to the bow. Not a problem for single shots, and also less so when repellng sieges. Andy Dingley (talk) 15:22, 30 December 2018 (UTC)[reply]
Thanks a lot, all! --Stephan Schulz (talk) 15:31, 30 December 2018 (UTC)[reply]
Actually 100 meters/yards per second/200 mph is bows designed for distance and mph [1], Medieval English longbows used heavier arrows (maybe Asia had less metal for armor?) and were more like 200 feet per second. Sagittarian Milky Way (talk) 17:43, 30 December 2018 (UTC)[reply]
Regarding "the English longbow is the ultimate weapon of all time" - I doubt that the average bomb would be bothered much by an arrow. ←Baseball Bugs What's up, Doc? carrots→ 01:25, 31 December 2018 (UTC)[reply]
Since OP's post was positively drooling in sarcasm I think you may have been sucked into a transatlantic troll's ambush. Greglocock (talk) 10:29, 31 December 2018 (UTC)[reply]
I almost got the point. It was an arrow escape. ←Baseball Bugs What's up, Doc? carrots→ 11:19, 31 December 2018 (UTC)[reply]
Oh, archer the funny one. DroneB (talk) 14:19, 31 December 2018 (UTC)[reply]
From my dealings with internet and politics, I would say... Newer users of the internet have trouble telling when they are reading sarcasm. More experienced users have trouble telling when they are writing sarcasm. Wnt (talk) 05:36, 1 January 2019 (UTC)[reply]
The Technological Development of the Bow and the Crossbow in the Later Middle Ages, Ph.D. Thesis by Stuart Gorman "In 1998, the Royal Armouries published a series of experiments led by Thom Richardson. These tests involved a wide range of [replica] weapons from the Middle Ages and earlier... The 72 and 90 lbs longbows both fired a bodkin headed arrow with average speeds of 41.65 metres per second (93 mph) and 43.47 metres per second (97 mph) respectively... The steel crossbow fired two different bodkin headed bolts built by different fletchers. These bolts travelled at an average speed of 44.6 metres per second (100 mph) and 43.9 metres per second (98 mph).... All of these weapons were also fired at a 2 mm thick piece of steel, but none of them was able to penetrate the sheet" (p. 59). He says a bit earlier on that arrows have a terminal velocity, so increasing the power of the bow may not increase the velocity very much - some of the longbows from the Mary Rose have been controversially rated at up to 140 lbs draw. There have been several other experiments but none seem to have made replica arrows fly as fast as 50 metres per second; you can read it yourself if you have time on your hands. The answer therefore is that it takes a war arrow a little more than two seconds to fly 100 metres but you're pretty safe if you've put your armour on properly. Alansplodge (talk) 22:05, 1 January 2019 (UTC)[reply]
I think you give distance weapons of the middle ages tomuch credit. Everyone, especially Army-Commanders and Knights knew about their potential and thus used siege shields aka Mantlets and alike protection to close in on an enemy army, camp, city or castle. In close combat or with cavalry hunting, anyone just wielding a bow, or worse a heavy clumsy crossbow, was toast in seconds. Also these where units the enemy cavalry usually went after first because they where so vulnerable. So against an prepared enemy these distance weapon where totally useless, often just Cannon fodder. --Kharon (talk) 21:15, 2 January 2019 (UTC)[reply]
Missile weapons become relevant for "targets of opportunity". For example, consider Battle of Lechaeum - not archers, not medieval, but it illustrates the idea that what seems like a "nuisance" in the military sense of the term can turn into a problem given half a chance. Or the Siege of Rome (537–538) where the deficiency of planning made for some moments of amusement. I imagine the persistent threat of a shaft sprouting from some uncomfortable place during any unguarded moment must have made medieval sieges seem even longer than they would otherwise. Wnt (talk) 17:30, 3 January 2019 (UTC)[reply]
But User:Kharon, yuu're talking about sieges. In open battle, the English longbow (specifically mentioned in the original question) was used to great effect as a barrage weapon at the Battle of Crécy (1346) at which 300 English were killed against a conservative estimate of 12,000 French. Similarly the Battle of Poitiers (1356) had "minimal" English losses against 2,500 French killed, and the Battle of Agincourt (1415) which has a modern estimate of 450 English deaths against the lowest figure of 4,000 French, but claims go as high as 11,000. Alansplodge (talk) 14:21, 5 January 2019 (UTC)[reply]
As for crossbows, Modern_competitive_archery#Crossbow_archery_(IAU_rules_internationally) says a modern crossbow with 43 kilo draw weight, 20 gram projectile and 12 inch draw length is 67 meters per second. Sagittarian Milky Way (talk) 18:32, 5 January 2019 (UTC)[reply]