Something for the experts - the shock of firing main guns

[Hotschi]

Reading Ronald H. Spector's Eagle Against The Sun, Vintage Press, I came across something which I have never heard of before;

On page 261 of the paperback edition, he writes:

Hills flagship, the battleship Maryland, had its communications center located on the flag bridge almost at the same level as the sixteen-inch guns. As a result, the shock of firing could knock out the delicate electronic gear and render the admiral temporarily unable to communicate with his commanders.

Copyright 1985 by Ronald H. Spector

and later that this, during the bombardement of Tarawa, at 04:40 actually happened.

Why this? I am no engineer, and I have always thought the recoil of the guns absorbs all the shock and everything is fine and dandy. How come that firing 16" guns had this effect? Is it because of the proximity of the guns and the electronics, as Spector writes? Would a different place for the installation of the "electronic gear" farther away from the guns, have made any difference? What was "at fault" here, the WW II era gun technology, the electronic technology, or simple physics and you can't change anything?

Next thought - the Iowas were loaded with tons of electronics after WW II, and still had their 16" guns. I reckon they didn't just retain them just for show or because they look cool, but used them every once in a while. Was there any similar effect after the war?

I am trying to imagine being on the Maryland, its guns blazing, and the whole ship trembles in shock. Was it really like this? Coffee cups flying around? [:D]

[dr.hal]

On a related note, I remember reading about HMS Agincourt, a ship that had the most centerline big gun turrets (7) of any dreadnaught. Prior to the battle of Jutland, the 14 guns were never all fired at once for fear that the ship might roll over, NO JOKE! When they were fired in a single salvo, every piece of china in the wardroom was broken as well as all the toilets in the ship!

[JeffroK]

1943 electronics were very fragile when compared to their 1945-46 versions.
I believe the RN & USN had struck this problem in the ETO around the same time. (Maybe at Dieppe Aug 42??)

[AW1Steve]

Vacum tube based tech. Tubes are thin glass, they break , or the tube unseats. Today we mostly use solid state.

[Hotschi]

Vacum tubes, that explains a lot. And no one thought of placing these things in cases which absorbs shocks - something with "rubber foots" or whatever?

Yes you are right, I am no electronic expert either - I know no nothing about these things. [:D]

Thanks for the explanations, JeffK and Steve, now I have a clue.

[JeffroK]

2 British examples of HQ Ships were HMS's Largs & Hilary.

http://freespace.virgin.net/mike.macken ... SLARGS.htm
http://bob.plord.net/Ships/Period3/Grea ... ilary.html

[JeffroK]

A bit more of an explanation, ETO only

http://www.combinedops.com/HEADQUARTERS%20SHIPS.htm

[btbw]

Shock from gas pressure. Too close fragile equipment can be destroyed by it - even boat/planes.
Shock from gun moving during shoot which might roll over ship it MYTH.
1. Main guns NEVER shoot once.
2. First shock get gun axis, then mount which NOT FIXED to ship.
3. Own moment of inertia of battleship much more then firing shells.
4. If shock from gun shoot dont compensated (and receiving by whole ship as punch) it destroy mount too fast. Even wooden ship era cannons had demphers or cannons will destroy fragile ship (and crew) better then enemy.
Video how much gas produce main guns.
http://youtu.be/mkx68UdcPA0

P.S. And old joke too (video mismatch but still funny) http://youtu.be/rZD62OhaDTI
P.P.S. And last one - how equipment on ship going to survive after hitting (and exploding) by enemy shell if own guns can destroy it? Very easy in really - fragile equipment hide after armor in isolated rooms and stay on springs. If room not isolated from gas pressure then admiral kicked out from action.

[JeffroK]

Plus trying to squeeze enough HQ types on a ship trying to double as a cambat ship doesnt help.

[Chris21wen]

ORIGINAL: Hotschi

Vacum tubes, that explains a lot. And no one thought of placing these things in cases which absorbs shocks - something with "rubber foots" or whatever?

Yes you are right, I am no electronic expert either - I know no nothing about these things. [:D]

Thanks for the explanations, JeffK and Steve, now I have a clue.

By the end of the war they certainly did, called vibration mounts but they were only effective up to a point. On a ship you can feel mechanical movement throughout the ship, which includes the recoil of any gun fired particularly if the recoil mechanisism of the gun does not fully counteract the discharge of the gun, and most didn't/couldn't, using the ship to absorb the rest. This is felt more on the same deck as the gun firing. Even today firing a gun or missile will make a ship roll. Early electronics were delicate, it's not just the glass valves/tubes but soldered joints that could be broken. The other thing that should be not was ships also had voice tubes so complete communications would not have been lost.

I've been on more than one ship were all power has been temporarily lost and it's eerily quite and, if it happens while asleep the whole ship wakes, quite often with just a hint of panic.

[btbw]

Again electronic equipment protected from stress of recoil and even hitting (except direct). But small size of Maryland and easy way to pressure can hurt equipment and admiral stuff.
If you think ship rotated from firing guns then all main guns must have a miss to target by all rounds except first in salvo.

[tigercub]

fire control and radar ,radio on many ships during ww2 was common place to have problems when the big ships were firing, also the first hit on a most warships often made many problems to any of the fire control and radar or radio!

[crsutton]

ORIGINAL: Hotschi

Reading Ronald H. Spector's Eagle Against The Sun, Vintage Press, I came across something which I have never heard of before;

On page 261 of the paperback edition, he writes:

Hills flagship, the battleship Maryland, had its communications center located on the flag bridge almost at the same level as the sixteen-inch guns. As a result, the shock of firing could knock out the delicate electronic gear and render the admiral temporarily unable to communicate with his commanders.

Copyright 1985 by Ronald H. Spector

and later that this, during the bombardement of Tarawa, at 04:40 actually happened.

Why this? I am no engineer, and I have always thought the recoil of the guns absorbs all the shock and everything is fine and dandy. How come that firing 16" guns had this effect? Is it because of the proximity of the guns and the electronics, as Spector writes? Would a different place for the installation of the "electronic gear" farther away from the guns, have made any difference? What was "at fault" here, the WW II era gun technology, the electronic technology, or simple physics and you can't change anything?

Next thought - the Iowas were loaded with tons of electronics after WW II, and still had their 16" guns. I reckon they didn't just retain them just for show or because they look cool, but used them every once in a while. Was there any similar effect after the war?

I am trying to imagine being on the Maryland, its guns blazing, and the whole ship trembles in shock. Was it really like this? Coffee cups flying around? [:D]

After fighting the Bismark the HMS Rodney was in such pitiful shape from the effects of her own guns that she had to go to the US for a major refit. If I recall she sprung some plates along with other damaged caused by the concussions of the 340 16 inch rounds she fired.

I read a great account of the Houston shredding one of her float planes with by the shock of her 8 inch guns.

[geofflambert]

I believe I once heard that when Yamato first fired those 18" guns, the shock crumpled the armored turrets of the secondary guns and knocked some off their tracks. [X(]

[btbw]

Changing plates after 340 rounds fired it some different from version of knocked out equip and admiral by gun recoil. And reason is - plate accumulate deformations around gun turret with each salvo. Equip and admiral - not, cuz they dont PLATE and dont stay FIXED as ship corpse.
And plane was shooted by GAS PRESSURE (like many other planes/boats and everything which close and OPEN to gas pressure). Maryland had CIC placed on flagbridge on SAME LEVEL and dimensions of Maryland lesser then Iowa with 16inches (so lesser range from gun to CIC).

[msieving1]

After fighting the Bismark the HMS Rodney was in such pitiful shape from the effects of her own guns that she had to go to the US for a major refit.

Rodney was on her way to the US for a major refit when she joined the chase for Bismark.

She did suffer damage from her own guns, even though she generally limited firing to 4 or 5 gun salvos.

According to http://www.naval-history.net

"The blast effects from RODNEY’s main armament caused the Douglas fir decking on the upper deck to be ripped up. Also the adoption of aluminium alloys for most of the minor ships fittings, such as kit lockers, mess racks, store cupboards and wash facilities caused all these fittings to be shaken up and some dislodged when the main armament was fired. Cast iron water mains were ruptured and in many instances broke, flooding compartments."

[MikeS4269]

(from the 50 second point)

http://www.youtube.com/watch?v=okKQeQZeJts

[Apollo11]

Hi all,

The Bismarck knocked its own radar off with the shock of firing the main battery as well...


Leo "Apollo11"

[Hotschi]

Thanks for all the links, something more to digest [;)]

Really, I wasn't aware of these things. I read a lot of books about WW II (primarily PTO) but didn't dig deep enough into the technical aspects of any equipment yet. There's so much available but just not enough time to read it all at once.

[borner]

Good point on the old electronice, and as Apollo mentioned, Bismark damaged her own radar. Also Yamato supposedly had big issues with shock from her main battery. It probably would have causes serious issues if she was in more than a short term gun duel with an allies fleet.