Topic Actions

Topic Search

Who is online

Users browsing this forum: No registered users and 67 guests

The next steps in gunnery w/ gunboats and Canals

This fascinating series is a combination of historical seafaring, swashbuckling adventure, and high technological science-fiction. Join us in a discussion!
Re: The next steps in gunnery.
Post by Down Under   » Sat Mar 07, 2015 11:37 pm

Down Under
Lieutenant (Senior Grade)

Posts: 72
Joined: Sat Apr 27, 2013 1:54 am
Location: New Zealand


Randomiser wrote
Yes it's quite surprising, but if you look at Captain Igloo's post of 6 Mar
LAMA Says
1)Holy Langhorne is built to accept barges 130x35 ft
2)later 'pre-gunpowder' canals are limited to no more than 110x10ft

MTaT says
3)Mainland really long haul barges are limited to about 125 ft
4)New Northland locks = Delthak locks can cope with 140x45 ft

So it looks like New Northland > Holy Langhorne > pre-gunpowder canals and the Delthaks can't operate on the Holy Langhorne. Except that 3) seems to contradict 2), so we may have a continuity error about the relative sizes of the canals between the books.


Is the problem the width of the canal or the width of the locks?

My observation while in Holland a few years ago was that in order to allow two-way traffic locks were half the width of the shipping lane.
Top
Re: The next steps in gunnery.
Post by Weird Harold   » Sun Mar 08, 2015 1:33 am

Weird Harold
Fleet Admiral

Posts: 4478
Joined: Thu Apr 24, 2014 10:25 pm
Location: "Lost Wages", NV

Down Under wrote:Randomiser wrote
Yes it's quite surprising, but if you look at Captain Igloo's post of 6 Mar
LAMA Says
1)Holy Langhorne is built to accept barges 130x35 ft
2)later 'pre-gunpowder' canals are limited to no more than 110x10ft

MTaT says
3)Mainland really long haul barges are limited to about 125 ft
4)New Northland locks = Delthak locks can cope with 140x45 ft

So it looks like New Northland > Holy Langhorne > pre-gunpowder canals and the Delthaks can't operate on the Holy Langhorne. Except that 3) seems to contradict 2), so we may have a continuity error about the relative sizes of the canals between the books.


Is the problem the width of the canal or the width of the locks?

My observation while in Holland a few years ago was that in order to allow two-way traffic locks were half the width of the shipping lane.


All of the textev deals with what the locks will handle -- which pretty much determines what the canal can handle.

If the Canal is built for two way traffic, then it will be twice-and-a-bit the width of the locks.

I don't think the "discrepancy" Randomizer noted is a continuity error -- the hand dug canals are probably not included in long-haul routing and have facilities for cross loading cargo where there is no other route.
.
.
.
Answers! I got lots of answers!

(Now if I could just find the right questions.)
Top
Re: The next steps in gunnery.
Post by lmwatbullrun   » Sun Mar 08, 2015 11:20 am

lmwatbullrun
Midshipman

Posts: 8
Joined: Sun Mar 08, 2015 10:57 am

History reminds us that the advent of steam power allows things like steam powered dredges to widen and deepen existing canals. Stirling in his "Islands" trilogy refers to this, and he is not the only one; I'd be shocked if Merlin omitted this innovation.

If I were the engineer in charge, I'd build my dredges small enough to fit the existing canals and widen use them to widen the canals enough to fit larger craft, such as Monitors, into the canal. Divers, diving bells, and timed charges can cope with most rock outcrops encountered, although steam dredges can cope with large boulders.

Ultimately, the COGA would be encircled and starved out. Given the potential for the COGA to use OWS strikes against specific targets, I expect that a diffuse offense would be employed to limit the potential exposure of Charis' armies.

As regards timed firing circuits, mechano-hydraulic controls would probably work almost as well as electrical firing circuits, and again, there is historic precedent for such things; there would be the need to calculate for the slight delay (lock time) of the mechanism, but again, this is well within Charisian abilities demonstrated to date. I was thinking that a large magnetically damped pendulum could "trip the trigger" and discharge a hydraulic pressure pulse to fire the guns.


Weird Harold wrote:
Down Under wrote:Randomiser wrote
Yes it's quite surprising, but if you look at Captain Igloo's post of 6 Mar
LAMA Says
1)Holy Langhorne is built to accept barges 130x35 ft
2)later 'pre-gunpowder' canals are limited to no more than 110x10ft

MTaT says
3)Mainland really long haul barges are limited to about 125 ft
4)New Northland locks = Delthak locks can cope with 140x45 ft

So it looks like New Northland > Holy Langhorne > pre-gunpowder canals and the Delthaks can't operate on the Holy Langhorne. Except that 3) seems to contradict 2), so we may have a continuity error about the relative sizes of the canals between the books.


Is the problem the width of the canal or the width of the locks?

My observation while in Holland a few years ago was that in order to allow two-way traffic locks were half the width of the shipping lane.


All of the textev deals with what the locks will handle -- which pretty much determines what the canal can handle.

If the Canal is built for two way traffic, then it will be twice-and-a-bit the width of the locks.

I don't think the "discrepancy" Randomizer noted is a continuity error -- the hand dug canals are probably not included in long-haul routing and have facilities for cross loading cargo where there is no other route.
Top
Re: The next steps in gunnery.
Post by Weird Harold   » Sun Mar 08, 2015 5:22 pm

Weird Harold
Fleet Admiral

Posts: 4478
Joined: Thu Apr 24, 2014 10:25 pm
Location: "Lost Wages", NV

lmwatbullrun wrote:If I were the engineer in charge, I'd build my dredges small enough to fit the existing canals and use them to widen the canals ...


There is some textev to suggest that Safeholdian canals are lined with stone or masonry. That would make widening a problem. Not to mention the need to rebuild locks to allow bigger boats.
.
.
.
Answers! I got lots of answers!

(Now if I could just find the right questions.)
Top
Re: The next steps in gunnery.
Post by isaac_newton   » Sun Mar 08, 2015 6:41 pm

isaac_newton
Rear Admiral

Posts: 1182
Joined: Fri Oct 18, 2013 6:37 am
Location: Brighton, UK

Down Under wrote:

Randomiser wrote
Yes it's quite surprising, but if you look at Captain Igloo's post of 6 Mar
LAMA Says
1)Holy Langhorne is built to accept barges 130x35 ft
2)later 'pre-gunpowder' canals are limited to no more than 110x10ft

MTaT says
3)Mainland really long haul barges are limited to about 125 ft
4)New Northland locks = Delthak locks can cope with 140x45 ft

So it looks like New Northland > Holy Langhorne > pre-gunpowder canals and the Delthaks can't operate on the Holy Langhorne. Except that 3) seems to contradict 2), so we may have a continuity error about the relative sizes of the canals between the books.


Is the problem the width of the canal or the width of the locks?

My observation while in Holland a few years ago was that in order to allow two-way traffic locks were half the width of the shipping lane.


From my rather limited experience of english canals/locks, the locks I saw were singletons. There are some serious 'staircases' of locks, e.g. http://en.wikipedia.org/wiki/Caen_Hill_Locks.

The canals themselves are however generally two way, except on some viaducts.

I had the feeling that the Safehold locks were paired - as per the Dutch ones mentioned above. In either case, I'd think it was the locks limiting the barge dimensions.
Top
Re: The next steps in gunnery.
Post by doug941   » Sun Mar 08, 2015 7:26 pm

doug941
Commander

Posts: 228
Joined: Sat May 03, 2014 6:21 pm

[quote="lmwatbullrun"]History reminds us that the advent of steam power allows things like steam powered dredges to widen and deepen existing canals. Stirling in his "Islands" trilogy refers to this, and he is not the only one; I'd be shocked if Merlin omitted this innovation.

If I were the engineer in charge, I'd build my dredges small enough to fit the existing canals and widen use them to widen the canals enough to fit larger craft, such as Monitors, into the canal. Divers, diving bells, and timed charges can cope with most rock outcrops encountered, although steam dredges can cope with large boulders.

Ultimately, the COGA would be encircled and starved out. Given the potential for the COGA to use OWS strikes against specific targets, I expect that a diffuse offense would be employed to limit the potential exposure of Charis' armies.

As regards timed firing circuits, mechano-hydraulic controls would probably work almost as well as electrical firing circuits, and again, there is historic precedent for such things; there would be the need to calculate for the slight delay (lock time) of the mechanism, but again, this is well within Charisian abilities demonstrated to date. I was thinking that a large magnetically damped pendulum could "trip the trigger" and discharge a hydraulic pressure pulse to fire the guns.

Rather than using a mechanical device, how about using a simple "time pencil"? Smaller, simpler, and doesn't run the risk of being stopped, either accidentally or by enemy action.

http://en.wikipedia.org/wiki/Pencil_detonator
Top
Re: The next steps in gunnery.
Post by Weird Harold   » Sun Mar 08, 2015 7:44 pm

Weird Harold
Fleet Admiral

Posts: 4478
Joined: Thu Apr 24, 2014 10:25 pm
Location: "Lost Wages", NV

doug941 wrote:Rather than using a mechanical device, how about using a simple "time pencil"? Smaller, simpler, and doesn't run the risk of being stopped, either accidentally or by enemy action.

http://en.wikipedia.org/wiki/Pencil_detonator


Time Pencils solve a different problem than firing a naval gun precisely when the ship is level in all directions.
.
.
.
Answers! I got lots of answers!

(Now if I could just find the right questions.)
Top
Re: The next steps in gunnery.
Post by doug941   » Sun Mar 08, 2015 8:00 pm

doug941
Commander

Posts: 228
Joined: Sat May 03, 2014 6:21 pm

Weird Harold wrote:
doug941 wrote:Rather than using a mechanical device, how about using a simple "time pencil"? Smaller, simpler, and doesn't run the risk of being stopped, either accidentally or by enemy action.

http://en.wikipedia.org/wiki/Pencil_detonator


Time Pencils solve a different problem than firing a naval gun precisely when the ship is level in all directions.


1mwatbullrun's post was concerning use of explosives and detonators by combat engineers to expand older canals.
Top
Re: The next steps in gunnery.
Post by lmwatbullrun   » Sun Mar 08, 2015 8:47 pm

lmwatbullrun
Midshipman

Posts: 8
Joined: Sun Mar 08, 2015 10:57 am

doug941 wrote:
Weird Harold wrote:
Time Pencils solve a different problem than firing a naval gun precisely when the ship is level in all directions.


1mwatbullrun's post was concerning use of explosives and detonators by combat engineers to expand older canals.


Actually, my intent, poorly expressed (my apologies!) was to address two different issues- one, Charisian access to the canal and lock system, and two, precise control of high angle naval gunfire. The trick is to fire the guns when everything is level and the ship is on course. This still leaves the problem of assessing point of impact versus point of aim, but as has been suggested elsewhere, tethered hot air balloons with semaphore could address this, or one could slide the message down the tether. This method was used during the 19th century.

As regards to the lock system, I would simply build another lock in parallel off to one side of the existing one, complete the new lock and then remove the earthen dam between the new canal and the new lock, bypassing the old structure completely. You would thus be able to maintain the existing system while you build the new one, and increase canal throughput by using the old locks for commercial traffic until the old canal boats wore out and were replaced.

And you are right, there are a number of ways that one could control fixed charge detonation, pencils being one. I recall that those used in WW1 were rather unreliable and even into WW2 quality control was a problem.....
Top
Re: The next steps in gunnery.
Post by RunsInShadows   » Mon Mar 09, 2015 12:01 pm

RunsInShadows
Lieutenant (Junior Grade)

Posts: 48
Joined: Tue Feb 17, 2015 12:12 pm
Location: New Hampshire

lmwatbullrun wrote:
And you are right, there are a number of ways that one could control fixed charge detonation, pencils being one. I recall that those used in WW1 were rather unreliable and even into WW2 quality control was a problem.....


Yep if not for that, then hitler might have come to an earlier end.
.
RIS

"Ack!" I said. Fearless master of the witty dialogue, that's me.
― Harry Dresden, Changes by Jim butcher
Top

Return to Safehold