Navy back to Sextant

[Steamchick]

Chazz: I was a Midshipman on a small inshore defence vessel - on the foredeck - supervising mooring lines - when there was a cry from the bridge "Emergency!! Let go all forrard"!!"
The manoeuvring engine single screw had cavitated due to an emergency change from Ahead to Astern. - This caused a "backed to starboard! " event - as you also experienced. I was told afterwards it was natural due to the density of air and water when cavitating, when a large quantity of air is "gulped-down" to the bottom of the screw, and the cavitation therefore causes reverse "paddle wheel" side thrust.
Not being quick enough, the Mid on one mooring rope (fore-spring) left it cleated, whereby the momentum of the ship simply snapped the 2 inch rope like rotten cotton! As the broken end whipped back it destroyed the hand-rails along the side of the foredeck.
Cavitation can cause a loss of control or response to the telegraph, so the telegraphist must always take care with his instructions and timing to the engine room... ALWAYS STOP-PAUSE - between Ahead and Astern. The Bridge MUST understand how the ship will respond to their instructions.
K2

 

[SmithDoor]

Chazz: I was a Midshipman on a small inshore defence vessel - on the foredeck - supervising mooring lines - when there was a cry from the bridge "Emergency!! Let go all forrard"!!"
The manoeuvring engine single screw had cavitated due to an emergency change from Ahead to Astern. - This caused a "backed to starboard! " event - as you also experienced. I was told afterwards it was natural due to the density of air and water when cavitating, when a large quantity of air is "gulped-down" to the bottom of the screw, and the cavitation therefore causes reverse "paddle wheel" side thrust.
Not being quick enough, the Mid on one mooring rope (fore-spring) left it cleated, whereby the momentum of the ship simply snapped the 2 inch rope like rotten cotton! As the broken end whipped back it destroyed the hand-rails along the side of the foredeck.
Cavitation can cause a loss of control or response to the telegraph, so the telegraphist must always take care with his instructions and timing to the engine room... ALWAYS STOP-PAUSE - between Ahead and Astern. The Bridge MUST understand how the ship will respond to their instructions.
K2

Building a engine Engine Telegraph would be fun project. The ones look a was electric control.

I pick a navy engine off a small boat by the size.
It was nice engine to rebuild.

The interesting part is control on was engine. You think navy would run a direct control to the bridge. Like the B29 had right beside the pilot all 4 engines. I have wounder how many ships would have been saved with direct controls. I told that rudder was same move need that told guy below to turn the ship.


Different Position on Engine Telegraph
Ahead Direction Movements:

Navigation full
Full Ahead
Half Ahead
Slow Ahead
Dead Slow Ahead
Stop


Astern direction movements:

Dead slow astern
Slow Astern
Half Astern
Full Astern
Emergency Astern


https://www.marineinsight.com/marine-navigation/the-basics-of-engine-order-telegraph/

I like see on a fighter aircraft flying like Navy ship uses.

 

[ChazzC]

Building a engine Engine Telegraph would be fun project. The ones look a was electric control.
View attachment 161483

I pick a navy engine off a small boat by the size.
It was nice engine to rebuild.

The interesting part is control on was engine. You think navy would run a direct control to the bridge. Like the B29 had right beside the pilot all 4 engines. I have wounder how many ships would have been saved with direct controls. I told that rudder was same move need that told guy below to turn the ship.


Different Position on Engine Telegraph
Ahead Direction Movements:

Navigation full
Full Ahead
Half Ahead
Slow Ahead
Dead Slow Ahead
Stop


Astern direction movements:

Dead slow astern
Slow Astern
Half Astern
Full Astern
Emergency Astern


https://www.marineinsight.com/marine-navigation/the-basics-of-engine-order-telegraph/

I like see on a fighter aircraft flying like Navy ship uses.

Engine Order Telegraph

Ships with Gas Turbines (Coast Guard Cutters and I think some USN ships) do have direct control of the engine room, but warships need systems that have multiple backups (sound powered communications between the bridge, engine room, steering control, comat information and weapons control for example).

 

[SmithDoor]

Engine Order Telegraph

Ships with Gas Turbines (Coast Guard Cutters and I think some USN ships) do have direct control of the engine room, but warships need systems that have multiple backups (sound powered communications between the bridge, engine room, steering control, comat information and weapons control for example).

Some of newer Airline liners have fly by wire similar RC uses.

The American war ships still use someone in engien room and steering rooms.

That sounds like Navy.
Like December 6 1941 use bombers to drop smoke bomb for a amying the battle guns to shoot the other side. They change that on December 8 1941. Could be no battle ships on the 7th

Dave

 

[Steamchick]

The engine telegraphs tell the Engine room what power is required. The setting/adjustment of regulators, etc. is down to a complex control run by a team of men.... or used to be when I was a lad.. (1970s Navy). Probably one microprocessor and a hundred servos do it today.... (Sail by wire? - Ok until water gets into the wires.... or the smoke escapes from the microprocessor!).
In steam ships, the setting of fuel supply to boilers, - especially when running a Nuclear powered boiler - management of steam pressure, throttle control and valve setting took more than a few people, following strict rules to keep the system "in balance". You could not trust a sailor to understand what the control was doing and make it all automatic - back in the day. - A sailor would normally only have a direct engine control on a Pinnace, or other small craft. But a good team - Captain, officers and crew, could put a large ship alongside and stop it within a yard or so of the exact position for the gang-plank etc. (A bad one would dent the ship!). Then the sailors could adjust ropes for the last foot - or inches - of position.
At night (Middle Watch), in harbour, I was on watch on a small boat (about 100 Tons) and with the other watchkeeper, we moved the ship along the wharf about 150 ft to a different berth using just the mooring ropes, to make room for another vessel to moor where we vacated the berth. It was at first light (Morning watch) when the No.1 and Captain (pre-breakfast) discovered the ship had moved berth, as everyone had slept through the manoeuvre. To use engines would have needed 2 Mechanicians for the engine room, a full watch of crew for the ropes, a Senior officer and junior Officer for supervision and direction, NCOs managing the helm, controls, communication, etc. But simply inching the boat with mooring ropes was easy - if very slow. And everyone slept peacefully.
On engine telegraphy: "Half-Ahead" was always accompanied by a "number of revolutions" for the particular shaft - by voice powered telephone or voice-pipe (works without electrical power). "Full" was "give us the best you can - it is an emergency!" - never used on my watch. The OOW never called for a "speed", of ship, only shaft revolutions, then the navigator worked out how fast were going position to position, and requested more or less "speed" accordingly. Wind and currents meant the ship moved differently by position (navigator speed) compared to "speed through water". With a following sea from a gale + tidal current we made 3Kn more than "maximum" for a watch where I was Helm. Beating into a storm sea and tide meant we made 3~4Kn less than aquatic speed on another occasion.
Steering was different. The Wheel directly actuated servos that managed the Steering engine - that steered the rudder(s). But in case of a problem, there was a mechanic and sailor in the steering flat on stand-by when in any action of harbour manoeuvring. The rudders could be moved by "Handraulic" means of the steering engine failed. That needed a sailor to power it, following the indicator from the bridge wheel - or other communication if battle damaged.
Lots of exercises kept everyone occupied when at sea.
K2

 

[Steamchick]

Hi Dave: re: "December 6 1941 use bombers to drop smoke bomb for aiming the battle guns to shoot the other side. They change that on December 8 1941. Could be no battle ships on the 7th" - Could be NO PLANES, NO Landing strips, no aircrew, too. But that was just at Pearl Harbour...
Actually, the ships carried their own optical sighting and ranging equipment in the "tops" - including radar (ranging) as it became available - but use of planes as spotters also helped. Especially when ships were "over the horizon" - or lost in the sea-level visibility. If you can shoot accurately at 12 miles, it matters not a jot when you cannot see through sea-level haze with less than 10 mile visibility. At Anzio and other land support operations, "Blanket bombing" was practiced as individual targets were invisible, especially after the smoke from the first few salvos. The first salvos were closest to the beach, after that the bombing was moved forward by small elevation increases - forming a "rolling bombardment" - supposed to drive the defending forces back from the beach. But first salvos caused a lot of smoke that obscured the rest of the bombardment. Complex mechanical computers were used to calculate gun elevation and firing point for the salvos because of ships pitch and roll. Needing inputs of ship's course, speed, target direction and supposed range, plus ship's attitude from pitch. roll and yaw. That was "the gunners' art". - All done by an electronic computer today...? Then in a fleet action the spotters had to determine which explosions were from their shells.. (by stop-watch!). Variation in the power of the cordite charge meant that in a salvo, shells could land plus -or minus - 100 yards from the intended target. Wind, etc could also affect range and direction. So the probability of more than 1 shell from a salvo hitting another ship 10miles away was very low. There was an element of luck (probability) combined with skill and engineering in the sinking of HMS Hood by Bismark. 1 hit was all it needed.
K2

 

[ChazzC]

The engine telegraphs tell the Engine room what power is required. The setting/adjustment of regulators, etc. is down to a complex control run by a team of men.... or used to be when I was a lad.. (1970s Navy). Probably one microprocessor and a hundred servos do it today.... (Sail by wire? - Ok until water gets into the wires.... or the smoke escapes from the microprocessor!).
In steam ships, the setting of fuel supply to boilers, - especially when running a Nuclear powered boiler - management of steam pressure, throttle control and valve setting took more than a few people, following strict rules to keep the system "in balance". You could not trust a sailor to understand what the control was doing and make it all automatic - back in the day. - A sailor would normally only have a direct engine control on a Pinnace, or other small craft. But a good team - Captain, officers and crew, could put a large ship alongside and stop it within a yard or so of the exact position for the gang-plank etc. (A bad one would dent the ship!). Then the sailors could adjust ropes for the last foot - or inches - of position.
At night (Middle Watch), in harbour, I was on watch on a small boat (about 100 Tons) and with the other watchkeeper, we moved the ship along the wharf about 150 ft to a different berth using just the mooring ropes, to make room for another vessel to moor where we vacated the berth. It was at first light (Morning watch) when the No.1 and Captain (pre-breakfast) discovered the ship had moved berth, as everyone had slept through the manoeuvre. To use engines would have needed 2 Mechanicians for the engine room, a full watch of crew for the ropes, a Senior officer and junior Officer for supervision and direction, NCOs managing the helm, controls, communication, etc. But simply inching the boat with mooring ropes was easy - if very slow. And everyone slept peacefully.
On engine telegraphy: "Half-Ahead" was always accompanied by a "number of revolutions" for the particular shaft - by voice powered telephone or voice-pipe (works without electrical power). "Full" was "give us the best you can - it is an emergency!" - never used on my watch. The OOW never called for a "speed", of ship, only shaft revolutions, then the navigator worked out how fast were going position to position, and requested more or less "speed" accordingly. Wind and currents meant the ship moved differently by position (navigator speed) compared to "speed through water". With a following sea from a gale + tidal current we made 3Kn more than "maximum" for a watch where I was Helm. Beating into a storm sea and tide meant we made 3~4Kn less than aquatic speed on another occasion.
Steering was different. The Wheel directly actuated servos that managed the Steering engine - that steered the rudder(s). But in case of a problem, there was a mechanic and sailor in the steering flat on stand-by when in any action of harbour manoeuvring. The rudders could be moved by "Handraulic" means of the steering engine failed. That needed a sailor to power it, following the indicator from the bridge wheel - or other communication if battle damaged.
Lots of exercises kept everyone occupied when at sea.
K2

Different Navies, different terminologies, but the same concepts.

On USN Nuclear Powered Ships & Subs, all orders/instructions in the Power Room were repeated twice (you don't want mistakes happening:

​

Engineer of the Watch (EOW): "Set Reactor #1 to 50%"​

Watch-Stander: "Set Reactor #1 to 50%, Aye, Sir"​

Engineer of the Watch (EOW): "Setting Reactor #1 to 50%, Aye"​

Watch-Stander: "Reactor #1 is Set to 50%, Sir"​

Engineer of the Watch (EOW): "Reactor #1 Set to 50%, Aye"​

​

On Subs, they did this same procedure at all watch stations, Conn, Weapons, etc. The Captain of the California (CGN 36) was trained at Power School and started in the Power Room, so we used this system on the bridge.

​

​

 

[SmithDoor]

Hi Dave: re: "December 6 1941 use bombers to drop smoke bomb for aiming the battle guns to shoot the other side. They change that on December 8 1941. Could be no battle ships on the 7th" - Could be NO PLANES, NO Landing strips, no aircrew, too. But that was just at Pearl Harbour...
Actually, the ships carried their own optical sighting and ranging equipment in the "tops" - including radar (ranging) as it became available - but use of planes as spotters also helped. Especially when ships were "over the horizon" - or lost in the sea-level visibility. If you can shoot accurately at 12 miles, it matters not a jot when you cannot see through sea-level haze with less than 10 mile visibility. At Anzio and other land support operations, "Blanket bombing" was practiced as individual targets were invisible, especially after the smoke from the first few salvos. The first salvos were closest to the beach, after that the bombing was moved forward by small elevation increases - forming a "rolling bombardment" - supposed to drive the defending forces back from the beach. But first salvos caused a lot of smoke that obscured the rest of the bombardment. Complex mechanical computers were used to calculate gun elevation and firing point for the salvos because of ships pitch and roll. Needing inputs of ship's course, speed, target direction and supposed range, plus ship's attitude from pitch. roll and yaw. That was "the gunners' art". - All done by an electronic computer today...? Then in a fleet action the spotters had to determine which explosions were from their shells.. (by stop-watch!). Variation in the power of the cordite charge meant that in a salvo, shells could land plus -or minus - 100 yards from the intended target. Wind, etc could also affect range and direction. So the probability of more than 1 shell from a salvo hitting another ship 10miles away was very low. There was an element of luck (probability) combined with skill and engineering in the sinking of HMS Hood by Bismark. 1 hit was all it needed.
K2

I agree

There was an element of luck (probability) combined with skill and engineering

The HMS Hood just had bad luck too.

It is how I was told by Navy pilots

December 6 1941 use bombers to drop smoke bomb for aiming the battle guns to shoot the other side. They change that on December 8 1941. Could be no battle ships on the 7th.

The Navy pilots had more fun tell there story. They problem left out a few facts because they where pilots.

The radar is one best tools we had.
The way England synced there RADAR off power grid was great too.

Thank you
Dave

 

[SmithDoor]

Different Navies, different terminologies, but the same concepts.

On USN Nuclear Powered Ships & Subs, all orders/instructions in the Power Room were repeated twice (you don't want mistakes happening:

​

Engineer of the Watch (EOW): "Set Reactor #1 to 50%"​

Watch-Stander: "Set Reactor #1 to 50%, Aye, Sir"​

Engineer of the Watch (EOW): "Setting Reactor #1 to 50%, Aye"​

Watch-Stander: "Reactor #1 is Set to 50%, Sir"​

Engineer of the Watch (EOW): "Reactor #1 Set to 50%, Aye"​

​

On Subs, they did this same procedure at all watch stations, Conn, Weapons, etc. The Captain of the California (CGN 36) was trained at Power School and started in the Power Room, so we used this system on the bridge.

​

​

Interesting
Thank you for sharing . Most of information on Navy I received came from Pilots

Dave

 

[ChazzC]

Interesting
Thank you for sharing . Most of information on Navy I received came from Pilots

Dave

Pilots used to be referred to as “brown shoe,” ship drivers were “black shoe.”