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Army mortars v screw galleys

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Re: Army mortars v screw galleys
Post by n7axw   » Tue Dec 15, 2015 1:51 am

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lyonheart wrote:Hi Don,

Isn't thread drift fascinating if not fun?

Regarding defending galleons at anchor; the screw galleys have a maximum speed of 8 knots for up to 40 minutes, a velocity of 11.7333 feet per second or some 255 seconds to cover the last 1000 yards to the ship although a target ~56-60 mils wide at 1000 yards ought to be easy to hit with its 8-10" gun, so shooting back may be moot.

There could be a COW 37mm type gun [1.5 lb shot] with a 5 round clip [RoF 90 RPM] as mounted on some WWI airplanes although 1-3 pounders seem far too light to be effective; ore a recoiless Davis gun in 1.57"/2lb, 2.45"/6lb, 3"/12lb sizes, the latter used by the USN for ASW in WWI, or a tube type rocket launcher with a couple of dedicated loaders firing from the ship's fighting tops.

At anchor, the sails are furled so they're not in the way, and in action fighting sail is out of the way of the lower 'fighting top, while the topmost has no such restrictions in the first place of course.

The Davis recoiless gun worked by firing a weight equal to the shell in the opposite direction made up of lead shot and grease, later it was redesigned so the steel case was ejected rearward as well as clearing the breach for the next round.

I suspect the upper fighting top could have 4 mounts for a pair of Davis guns or rocket tube launchers while the lower could have 6 or 8 mounts for 3-4.

Because the angle to the screw galley might be too acute, the shell might require a spike to keep it from ricocheting off the deck, even if that complicates loading.

L



Hi Lyonheart,

Yep. It is fascinating, although this thread really hasn't drifted very far.

Maybe your idea works, although I've sort of come to think that the best defense might be waving a white flag... :lol:

With the rockets in tubes, I take it that one end is closed to prevent the thrust from torching anything in its rear?? Or perhaps to aim??

What you would get by putting the stuff in the tops to provide angle over the front castle of the screw galley?

Of course that only works as long as you are at anchor. In the event of a situation where the galleons are trying to get away, full sail would be set. I'm thinking of Abhaht's ssquadron here in the narrows.

A couple more thoughts come to mind. First, changing out some of those thirty pounders on the galleon for the same guns that a Rottweiler has would have to be a very unpleasant experience for the galleys. Given size and weight, you'd probably have to give up two old style cannon for each rifled cannon you gained. But I bet the exchange would be worthwhile. And a stern chaser could give a pursuing galley a very long day.

The other thought that comes to mind is that the screw galleys are a limited threat. They were able to operate as they did in an enclosed bay under conditions so calm that the galleons were having difficulty making way. Under normal blue water conditions, the galleys can't successfully operate and are thus not a threat.

It would be interesting to hear what the rest of you guys think of putting those wire wound rifled cannon on the older style war galleons, though. Maybe 2 or perhaps 4 on each side with at least 1 stern chaser... If it can be done, it's obviously worthwhile, but is it doable?

Don

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Re: Army mortars v screw galleys
Post by Darman   » Tue Dec 15, 2015 1:56 am

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Why not try to mount a large-bore rifled pivot gun fore and aft on galleons? Yes, it would have limited firing arcs, but it you mounted it on a circular rail system on the deck... then maybe it would have sufficient punch to at least harry/harass the screw galleys.
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Re: Army mortars v screw galleys
Post by evilauthor   » Tue Dec 15, 2015 3:10 am

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lyonheart wrote:Hi JeffEngel,

According to HFQ, Lt. Zhwaigair had dubbed them 'cranksmen', which certainly sounds more impressive than 'pedalmen'; which may be why RFC is the author of all this, NTM our hopes and dreams for the next fix in the series.

L


I think the reason they're not "pedalmen" is because Zhwaigair has no idea that bicycles exist. Ever description of the crank I can remember reading suggests the cranksmen are turning the crank using their arms, not their legs. I don't think it has even occurred to Zhwaigair to use leg power for his screw galleys.

Now, if Zhwaigair survives the war and Dohlar starts importing bicycles, he'll probably slap himself for missing something so obvious as pedal power.
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Re: Army mortars v screw galleys
Post by Louis R   » Tue Dec 15, 2015 12:52 pm

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I suspect that the actual motion is quite similar to the traditional rowing motion, which does involve legs and backs as well as arms.

Rowing galleys is highly-skilled work - something never left to slaves. In fact, it's so highly skilled that once Athens became dependent on her fleet for her military position in Greece [Athenian infantry was every bit as good as Spartan, as Marathon showed, but it was the fleet that gave her her strategic reach], the upper classes were left with no choice but to allow the landless men on the rowing benches not only full voting rights but the right to hold public office: the so-called Radical Democracy of Classical Athens.

That same dependence on skilled rowers will be at the heart of the relative egalitarianism that marks Charis, and to at least some extent the rest of the Out Islands [we don't really see them, but I'll lay odds it's particularly strong in Tarot and Emerald]. It's the equivalent dependence on the man in the ranks of the pike regiments that underlies Siddarmark's political system - and especially the strains it was starting to show in the 890s.

evilauthor wrote:
lyonheart wrote:Hi JeffEngel,

According to HFQ, Lt. Zhwaigair had dubbed them 'cranksmen', which certainly sounds more impressive than 'pedalmen'; which may be why RFC is the author of all this, NTM our hopes and dreams for the next fix in the series.

L


I think the reason they're not "pedalmen" is because Zhwaigair has no idea that bicycles exist. Ever description of the crank I can remember reading suggests the cranksmen are turning the crank using their arms, not their legs. I don't think it has even occurred to Zhwaigair to use leg power for his screw galleys.

Now, if Zhwaigair survives the war and Dohlar starts importing bicycles, he'll probably slap himself for missing something so obvious as pedal power.
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Re: Army mortars v screw galleys
Post by JeffEngel   » Tue Dec 15, 2015 3:40 pm

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Louis R wrote:I suspect that the actual motion is quite similar to the traditional rowing motion, which does involve legs and backs as well as arms.
Certainly they'd like to arrange that to make the most of rowing experience. Do we have an idea or speculation about how the cranksmen are set up and the whole process of conversion of their movement to screw turning? (There's probably been at least a partial description in the books, but I've no recollection of it whatever and I'd love any refresher anyone has on offer.)
Rowing galleys is highly-skilled work - something never left to slaves. In fact, it's so highly skilled that once Athens became dependent on her fleet for her military position in Greece [Athenian infantry was every bit as good as Spartan, as Marathon showed, but it was the fleet that gave her her strategic reach], the upper classes were left with no choice but to allow the landless men on the rowing benches not only full voting rights but the right to hold public office: the so-called Radical Democracy of Classical Athens.

That same dependence on skilled rowers will be at the heart of the relative egalitarianism that marks Charis, and to at least some extent the rest of the Out Islands [we don't really see them, but I'll lay odds it's particularly strong in Tarot and Emerald]. It's the equivalent dependence on the man in the ranks of the pike regiments that underlies Siddarmark's political system - and especially the strains it was starting to show in the 890s.

It would also underline the next-on-the-list suspicion had by Clyntahn for Dohlar - that galley fleet would make for a social status and military weight for people outside the land and horse set, just as manufacture and trade make for political and economic weight for the shopkeepers and whatever-wrights.

Still though, the galley fleets by population for Emerald, Tarot, Charis before Merlin were all much smaller by population than Athens had, right? Safehold's had a whole lot more population density than classical Greece, and a far less bloody recent history and current expectations (then!) under Pax Zion.
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Re: Army mortars v screw galleys
Post by Louis R   » Tue Dec 15, 2015 5:44 pm

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It's not so much the proportion of the population as it is the proportion of royal power they represent. For the Ahrmahks, it would have been substantial. For the Daikyns, much less so, although I suspect not entirely negligible; in Desnair, not even on the radar.

In Athens, it wasn't a huge portion of the population either. But then, we shouldn't forget that even in liberal Athens citizens were maybe 10% of the population.

JeffEngel wrote:
Still though, the galley fleets by population for Emerald, Tarot, Charis before Merlin were all much smaller by population than Athens had, right? Safehold's had a whole lot more population density than classical Greece, and a far less bloody recent history and current expectations (then!) under Pax Zion.
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Re: Army mortars v screw galleys
Post by gamarus   » Wed Dec 16, 2015 6:48 am

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JeffEngel wrote:
Louis R wrote:I suspect that the actual motion is quite similar to the traditional rowing motion, which does involve legs and backs as well as arms.
Certainly they'd like to arrange that to make the most of rowing experience. Do we have an idea or speculation about how the cranksmen are set up and the whole process of conversion of their movement to screw turning? (There's probably been at least a partial description in the books, but I've no recollection of it whatever and I'd love any refresher anyone has on offer.)


I can't recall any mention of it either but I have imagined it like the crankshaft on the Hunley. Cranksmen standing on opposite sides of an oversized crankshaft.

Picture of the Hunley's crank arrangement:
https://www.google.dk/search?q=css+hunley&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjzsZ3mmeDJAhXD6CwKHUivCbMQ_AUIBygB&biw=1680&bih=869#imgrc=wDHEsdJEx3MQtM%3A
And how the men would work:
https://www.google.dk/search?q=css+hunley&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjzsZ3mmeDJAhXD6CwKHUivCbMQ_AUIBygB&biw=1680&bih=869#imgrc=SmMV2Ur-E44HyM%3A

Don't know if the optimum is a two-stroke like the Hunley's or it would be better to have fewer men on the actual stroke but a more optimum use of the torque.
(two men: if they start with the crank in vertical position, can't provide their full mechanical force. one will be pulling up towards his chest, the other pushing down away. at horizontal one will start to push down and away from his chest, the other will do nearly nothing trying to lift the bar up and away. Splitting the motion will have more 'slack' but always one doing the optimum motion.)
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Re: Army mortars v screw galleys
Post by JeffEngel   » Wed Dec 16, 2015 10:16 am

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gamarus wrote:
JeffEngel wrote:Certainly they'd like to arrange that [classic rowing arrangement] to make the most of rowing experience. Do we have an idea or speculation about how the cranksmen are set up and the whole process of conversion of their movement to screw turning? (There's probably been at least a partial description in the books, but I've no recollection of it whatever and I'd love any refresher anyone has on offer.)


I can't recall any mention of it either but I have imagined it like the crankshaft on the Hunley. Cranksmen standing on opposite sides of an oversized crankshaft.

Picture of the Hunley's crank arrangement:
https://www.google.dk/search?q=css+hunley&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjzsZ3mmeDJAhXD6CwKHUivCbMQ_AUIBygB&biw=1680&bih=869#imgrc=wDHEsdJEx3MQtM%3A
And how the men would work:
https://www.google.dk/search?q=css+hunley&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjzsZ3mmeDJAhXD6CwKHUivCbMQ_AUIBygB&biw=1680&bih=869#imgrc=SmMV2Ur-E44HyM%3A

Don't know if the optimum is a two-stroke like the Hunley's or it would be better to have fewer men on the actual stroke but a more optimum use of the torque.
(two men: if they start with the crank in vertical position, can't provide their full mechanical force. one will be pulling up towards his chest, the other pushing down away. at horizontal one will start to push down and away from his chest, the other will do nearly nothing trying to lift the bar up and away. Splitting the motion will have more 'slack' but always one doing the optimum motion.)

Hmm. The Hunley's hull form and size meant they pretty much needed to arrange the men in a single line front to back. Screw galleys aren't in that position. Also, the Confederacy didn't have trained galley rowing crews they'd want to tap for propulsion if they could, so using a rowing motion would not have been important. Last, I do wonder if moving perpendicular to your own orientation wouldn't made the Hunley crew queasy or disoriented over enough time, making that arrangement something you'd avoid if you could - and a screw galley could do so.

With something like oar handles attached to a shaft by a hinge, you could transmit rowing motion to the shaft. It'd slide forward and back. You'd then need gearing in the back to transform that motion into propeller spinning - preferably steady spinning instead of bursts from the shaft moving back and forth. I'm not the engineer to speculate about how to do that, but my WAG is that it'd be possible. (Likely using a flywheel?)
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Re: Army mortars v screw galleys
Post by lyonheart   » Wed Dec 16, 2015 9:29 pm

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Hi JeffEngel,

Speaking of flywheels, the was the the USN's Howell torpedo, which as it happens didn't require electricity, being first demonstrated in 1870 and kept the USN from adopting the Whitehead for decades, though the Howell had some interesting advantages, being wake-less with gyroscopic control and a speed of 25 knots.

Just an FYI. ;)

L


JeffEngel wrote:
gamarus wrote:*quote="JeffEngel"*
Certainly they'd like to arrange that [classic rowing arrangement] to make the most of rowing experience. Do we have an idea or speculation about how the cranksmen are set up and the whole process of conversion of their movement to screw turning? (There's probably been at least a partial description in the books, but I've no recollection of it whatever and I'd love any refresher anyone has on offer.)
*quote*

I can't recall any mention of it either but I have imagined it like the crankshaft on the Hunley. Cranksmen standing on opposite sides of an oversized crankshaft.

Picture of the Hunley's crank arrangement:
https://www.google.dk/search?q=css+hunley&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjzsZ3mmeDJAhXD6CwKHUivCbMQ_AUIBygB&biw=1680&bih=869#imgrc=wDHEsdJEx3MQtM%3A
And how the men would work:
https://www.google.dk/search?q=css+hunley&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjzsZ3mmeDJAhXD6CwKHUivCbMQ_AUIBygB&biw=1680&bih=869#imgrc=SmMV2Ur-E44HyM%3A

Don't know if the optimum is a two-stroke like the Hunley's or it would be better to have fewer men on the actual stroke but a more optimum use of the torque.
(two men: if they start with the crank in vertical position, can't provide their full mechanical force. one will be pulling up towards his chest, the other pushing down away. at horizontal one will start to push down and away from his chest, the other will do nearly nothing trying to lift the bar up and away. Splitting the motion will have more 'slack' but always one doing the optimum motion.)

Hmm. The Hunley's hull form and size meant they pretty much needed to arrange the men in a single line front to back. Screw galleys aren't in that position. Also, the Confederacy didn't have trained galley rowing crews they'd want to tap for propulsion if they could, so using a rowing motion would not have been important. Last, I do wonder if moving perpendicular to your own orientation wouldn't made the Hunley crew queasy or disoriented over enough time, making that arrangement something you'd avoid if you could - and a screw galley could do so.

With something like oar handles attached to a shaft by a hinge, you could transmit rowing motion to the shaft. It'd slide forward and back. You'd then need gearing in the back to transform that motion into propeller spinning - preferably steady spinning instead of bursts from the shaft moving back and forth. I'm not the engineer to speculate about how to do that, but my WAG is that it'd be possible. (Likely using a flywheel?)
Any snippet or post from RFC is good if not great!
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Re: Army mortars v screw galleys
Post by PalmerSperry   » Sat Dec 19, 2015 11:59 am

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JeffEngel wrote:The hedgehog was used for depth charge distribution against a submarine that wasn't localized beyond over-there-ish - you got "accuracy" under those conditions just by hosing down an area with pain. Surface fighting wouldn't have that kind of need except in case of fighting in the dark or thick fog, but the sub could be put out of action or driven off by underwater detonations that may not do much good against a ship when they go off in air.


Whilst Hedgehog was an anti-submarine weapon it didn't fire depth charges, the warheads where impact fused so you either hit the submarine and got a bang or missed and got nothing ... There was thus no chance of any near-miss damage.

The later Squid and post-war Limbo systems did fire depth charges. Double-Squid which was two linked Squid systems firing 6 depth charges set to detonate 3 above the submarine and 3 below was especially lethal! (Though the war was basically over by the time it was widely available.)
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