No-deck-penetration guns mounts

adroth

New Member
Gents,

Am looking for references to bolt-on gun mounts that do not require structural modification to the ship that will use them -- the so called "no deck penetration" mounts.

Found the following thus far, I was wondering if there are were more out there.

Rafael Typhoon (Israel): http://www.israeli-weapons.com/weapons/naval/typhoon/Typhoon.html

MSI Defense DS25/DS30/SIGMA (UK): http://www.msi-dsl.com/naval.html

Oto Melara (Italy): http://www.otomelara.it/products/products.asp?id=prod_naval_small

Rheinmetall Light Naval Gun Mounts (Germany): http://www.rheinmetall-detec.de/index.php?fid=1518&lang=3&pdb=1
 

harryriedl

Active Member
Verified Defense Pro
Gents,

Am looking for references to bolt-on gun mounts that do not require structural modification to the ship that will use them -- the so called "no deck penetration" mounts.

Found the following thus far, I was wondering if there are were more out there.

Rafael Typhoon (Israel): http://www.israeli-weapons.com/weapons/naval/typhoon/Typhoon.html

MSI Defense DS25/DS30/SIGMA (UK): http://www.msi-dsl.com/naval.html

Oto Melara (Italy): http://www.otomelara.it/products/products.asp?id=prod_naval_small

Rheinmetall Light Naval Gun Mounts (Germany): http://www.rheinmetall-detec.de/index.php?fid=1518&lang=3&pdb=1
don't forget Phalanx. can't think of any other at the moment
 

kato

The Bunker Group
Verified Defense Pro

adroth

New Member
  • Thread Starter Thread Starter
  • #4
Seaguard ILDS (GADM-008 Millenium Gun).
BAE/Rafael Mk 38 Mod 2.
MSG/Kollmorgen Mk 98.
Sagem Sea Rogue.
Giat (Nexter) Narwhal.

Some that are on NavWeaps:

Breda 40mm Single/Twin Compact Type B.
DCN/Giat Affut 15A/15B

An older System:

Breda Twin 30mm Compact Type C (never sold afaik, and Navweaps doesn't mention the Type C; presumably the 25mm Type C version doesn't have deck penetration either, as the turrets are "identical").

Maybe i'll dig out some more later.
Super thanks for the leads Mr K. :D
 

Systems Adict

The Bunker Group
Verified Defense Pro
While I appreciate your comments about the guns specified being "No Deck Penetrations", most of ships these guns are designed to fit have specifically designed, stiffened / strengthened seats, which are fitted to the vessel during initial construction, or during a refit.

The reason being most deck plate on modern ships is approx 8 - 15mm thick. Even with stiffening underneath to support the plates at say every 24 inches, the flexing of the deck would form & set-up a harmonic effect in the deck plate, every time the weapon is fired.

The Harmonic frequency would affect accuracy, & could over a period of time actually make the plate brittle, or cause it to make the bolting arrangements sheer.

Most gun mounts are put onto a thick, solid steel plate/seat, which is machined down, to give an accurate flatness. The seat is then aligned accurately with other weapons systems (e.g. gyro compass / trackers / radar systems), then drilled using a drilling jig, thus providing the much improved tolerances that modern fire control systems need.

Even phalanx (which is classed as an "out of the box" system), is usually mounted to a seat help prevent such things.


Hope this helps your understanding of such things...


Systems adict

:wave
 

adroth

New Member
  • Thread Starter Thread Starter
  • #6
Hope this helps your understanding of such things...


Systems adict

:wave
Yes sir, it does. Thank you very much for sharing.

A USN vet, who posted on this thread's sister thread on another forum, reported that back in the 80's when they had to install the Phalanx on the Spruance class for the first time, they had to make modifications to the deck where the gun was actually mounted. So its really not just a case of welding the gun on the deck.

Could I ask for your permission to repost the information you shared below on our forum? There, the "zero-deck" issue is really only part of the picture.

While I appreciate your comments about the guns specified being "No Deck Penetrations", most of ships these guns are designed to fit have specifically designed, stiffened / strengthened seats, which are fitted to the vessel during initial construction, or during a refit.

The reason being most deck plate on modern ships is approx 8 - 15mm thick. Even with stiffening underneath to support the plates at say every 24 inches, the flexing of the deck would form & set-up a harmonic effect in the deck plate, every time the weapon is fired.

The Harmonic frequency would affect accuracy, & could over a period of time actually make the plate brittle, or cause it to make the bolting arrangements sheer.

Most gun mounts are put onto a thick, solid steel plate/seat, which is machined down, to give an accurate flatness. The seat is then aligned accurately with other weapons systems (e.g. gyro compass / trackers / radar systems), then drilled using a drilling jig, thus providing the much improved tolerances that modern fire control systems need.

Even phalanx (which is classed as an "out of the box" system), is usually mounted to a seat help prevent such things.
 

gf0012-aust

Grumpy Old Man
Staff member
Verified Defense Pro
While I appreciate your comments about the guns specified being "No Deck Penetrations", most of ships these guns are designed to fit have specifically designed, stiffened / strengthened seats, which are fitted to the vessel during initial construction, or during a refit.

The reason being most deck plate on modern ships is approx 8 - 15mm thick. Even with stiffening underneath to support the plates at say every 24 inches, the flexing of the deck would form & set-up a harmonic effect in the deck plate, every time the weapon is fired.

The Harmonic frequency would affect accuracy, & could over a period of time actually make the plate brittle, or cause it to make the bolting arrangements sheer.

Most gun mounts are put onto a thick, solid steel plate/seat, which is machined down, to give an accurate flatness. The seat is then aligned accurately with other weapons systems (e.g. gyro compass / trackers / radar systems), then drilled using a drilling jig, thus providing the much improved tolerances that modern fire control systems need.

Even phalanx (which is classed as an "out of the box" system), is usually mounted to a seat help prevent such things.


Hope this helps your understanding of such things...


Systems adict

:wave
Nicely put. I was involved with a recoil weapons testing program a few years back and we had some substantial discussions with companies such as Otto-Breda etc...

One of the reasons why they were keen to look at the tech was that on surface mount non penetrating systems there was still a considerable degree of work required to brace and stabilise the deck plates and structural support members due to recoil and reverb (or as you have stated, harmonic storage and transmission)

So, its not entirely accurate to imply that non penetrating deck mount systems are actually that, there is a certainly a degree of bracing that has to be in place, and if not in place, then a support cradle needs to take that into account.

Put it another way, a 120mm weapon will exert anything from 15 tonnes recoil generated energy, so if that energy is not managed, then you can start to kiss your deck goodbye.

You just can't go and upgun a platform because it has spare real estate available. Even if you go to a less intrusive deck mount, the amount of effort required to stabilise that deck area is considerable - and in most cases will be major surgery on the superstructure.

There are no free rides in mounting any ballistic weapons systems...
 

AegisFC

Super Moderator
Staff member
Verified Defense Pro
Yes sir, it does. Thank you very much for sharing.

A USN vet, who posted on this thread's sister thread on another forum, reported that back in the 80's when they had to install the Phalanx on the Spruance class for the first time, they had to make modifications to the deck where the gun was actually mounted. So its really not just a case of welding the gun on the deck.

Could I ask for your permission to repost the information you shared below on our forum? There, the "zero-deck" issue is really only part of the picture.
The Spruances had "low observable mounts" installed when they put Phalanx on them, the mounts look like what the Burkes have, most of the equipment was inside the ship except for the actual mount.
A better example of just bolting a Phalanx in place would be on the older US Frigates (like the Knox class) where they just pretty much just bolted it back aft and hooked up a line from the fire main for cooling.
 

Systems Adict

The Bunker Group
Verified Defense Pro
...Are you saying that they were just bolted to the deck & had power & cooling water added, nothing else??

Not even a stub framed seat, 6-8 inches high & 6 feet square, as is the norm ??
 

adroth

New Member
  • Thread Starter Thread Starter
  • #10
...Are you saying that they were just bolted to the deck & had power & cooling water added, nothing else??

Not even a stub framed seat, 6-8 inches high & 6 feet square, as is the norm ??
The USN vet on the other forum actually described an installation process on the old Spruance that was similar to what you described. Damage to the deck plate was indeed a concern.

Reportedly a plate was mounted on the deck, upon which the gun itself was mounted, and then reinforcement was added underneath the deck. No mention of the thickness of the plate though.
 

adroth

New Member
  • Thread Starter Thread Starter
  • #12
Most gun mounts are put onto a thick, solid steel plate/seat, which is machined down, to give an accurate flatness. The seat is then aligned accurately with other weapons systems (e.g. gyro compass / trackers / radar systems), then drilled using a drilling jig, thus providing the much improved tolerances that modern fire control systems need.
Finally found a photograph of the 25mm gun mount from MSI that was installed on our Jacinto class (previous RN Peacock class) patrol boats. The mount is under a tarp, but the seat is clearly visible.

http://timawa.net/forum/index.php/topic,10502.msg95732.html#msg95732

The seat isn't even just a plate . . . looks like there's a whole lot more to it than that.
 

Systems Adict

The Bunker Group
Verified Defense Pro
Thanks for the link & the Pics...

The "Seat" idea is also used for MSI's 30mm cannons (that have been fitted on lots of other RN / RFA ships & the Malaysian / Brunei Corvettes built by Yarrow / GEC / BAE).

Although these seats are usually circular in shape, with the mount bolting directly to it (rather than a flat plate,which has the gun attached to it), I do like the square look & the fins.

Systems Adict
 
Top