Communication with battleships (WWII)

Radio worked, but there were issues about directional finding. If you want a good story that involves radio issues, read Pursuit: The Chase and Sinking of the Bismark, by Kennedy. One of the reasons the Bismark was found because of some radio signals that it made.

Best of luck,

Jim Clark-Dawe

Yes, code breaking was a big thing in World War II. We used Navajo Indians for protection. Pearl Harbor was partially broken by code. I can't think of the name for England's program to decipher Germany's secrets. I just remember they captured the machine for deciphering way before the Germans realized it.

Best of luck,

Jim Clark-Dawe

Not the radio itself (radio technology wasn't quite that advanced at the time), but surely any military message sent by radio would be encrypted (manually and/or by a separate machine from the radio).

Google enigma machine. There are many sites on it, as it played a very significant role in WWII. This from wikipedia should suggest that you do more research on it:

The German military model, the Wehrmacht Enigma, is the version most commonly discussed. The machine has gained notoriety because Allied cryptologists were able to decrypt a large number of messages that had been enciphered on the machine. Decryption was made possible in 1932 by Polish cryptographers Marian Rejewski, Jerzy Różycki and Henryk Zygalski from Cipher Bureau. In mid-1939 reconstruction and decryption methods were delivered from Poland to Britain and France. The intelligence gained through this source, codenamed ULTRA, was a significant aid to the Allied war effort. The exact influence of ULTRA is debated, but a typical assessment is that the end of the European war was hastened by two years because of the decryption of German ciphers.[citation needed]

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You can encrypt radio signals, but that won't protect them from direction finding.

The rule of thumb is "if you hold the button down for more than five seconds, you WILL be spotted. Do it more than three times and you will get to hear artillery up close and personal."

Battleship communicating with other ships in the fleet would use a combination of radio, flags, signal lights and couriers (small fast boats or running lines between the boats and sending someone across (but that would have to be DAMN important)). A battle group could communicate back to it's headquarters either through HF radio or relaying messages to reconnaissance planes. Usually though, they sailed under radio silence until they commenced their attack. Then it didn't matter the enemy probably knew where they were then. *grin*

Glad to be of help.

I spent 15+ years in Military Intel, mostly working tactical communications. If you have any specific questions, I'll be happy to answer up to what I can. However, some stuff I'd have to decline to answer. I'm in no real hurry to make big rocks into little ones at Leavenworth. *grin*

Radio silence was usually just one way, ships could listen just didn't want to send. Battleships carried radio equipped spotter planes with observer radio operators that could facilitate sending morse messages several hundred miles away from the ship. I believe almost all message traffic was by hand key and the high speed stuff didn't come until after the war. Coding and decoding was time consuming. Voice radio was usually quite limited in range or required a very high powered transmitter. Two watts with good conditions and a great antenna could get a morse signal across the Pacific but a hundred watts and voice might not reach a hundred miles.

Douglas Reeman wrote a lot of WW2 stories set either on submarines or in warships, often in convoys, which can give an idea of what was used, and how. I went through a phase of reading them, years ago.

The Cruel Sea, by Nicholas Monserrat, (also a film with Jack Hawkins) was also a factually based story of a minesweeper in WW2, the Compass Rose.

Never thought about radio direction finding. They should have sent off a dozen little dinghies, each with a bloke and a radio, and started them sending messages miles away from the actual battleship.

Evaine said:

The Cruel Sea, by Nicholas Monserrat, (also a film with Jack Hawkins) was also a factually based story of a minesweeper in WW2, the Compass Rose.

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I'll vouch for this one. I read it when I was a kid (don't ask) and I really, really enjoyed it. Very vivid storytelling.

Here's an interesting factoid.

During WWII, when a ship left port, its destination was classified. So, the commanders at the port they left didn't always know where the ship was headed. And, the commanders at the port they were bound for didn't always know when to expect them.

When the U.S.S. Indianapolis (a heavy cruiser) left Guam for Leyete in the South Pacific and sunk on the way, no one noticed that the ship was missing. They all assumed that it had just been assigned somewhere else. Something like 1,200 men were in the water for days, being eaten by sharks and dying of burns sustained when the ship sank. Only about 300 or so survived. (The numbers are from memory, so I might be off a bit.)

Even when an American pilot sighted men in the water, he was told it was impossible because no ship was missing. He was ordered to continue his mission. The pilot defied orders, and remained circling over the men in the water until help arrived. He also dropped all the rafts, food, water and survival gear that he had with him. Eventually, I believe, his plane ran out of fuel and he ditched it in the water near the survivors, continuing to call for help on his radio. I think 300 of the men died during that last day, when the pilot had located them but rescuers had not yet arrived.

Because of this incident, the Navy changed their policy near the end of WWII so that someone knew where each ship was supposed to be at all times.

If you’d like to read a great real-life tale of heroism, try “In Harm’s Way: The Sinking of the U.S.S. Indianapolis and the Extraordinary Story of Its Survivors” by Doug Stanton.

maestrowork said:

Thanks. My story happened right around Pearl Harbor (although not at Pearl Harbor). So would the ships and the command posts know where the ships were? And would they know if the ship had been attacked and sunk?

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I don't know when this tactic started. I suspect that it was right after Pearl, when the philosophy was "loose lips sink ships." (In this case, literally, since an incautious comment to a Japanese collaborator could mean a sub attack.) I think up to Pearl Harbor, it was pretty common for sailors to tell their girls where their ship was going and when they would be back. The Japanese had pretty good information about what ships would be at Pearl Harbor when they attacked.

If a ship was sunk in sight of other U.S. ships, then the other ships would report it. However, if a ship was on a mission alone, and sank suddenly (as the Indianapolis did), the Navy might never know the truth. To this day, some ships are listed as "Presumed sunk with all hands near the Solomon Islands about May 16, 1944..." or whatever. At other times, survivors or debris were found in the water.

If you need someone to know about your ship sinking, you can give the radio operator just enough time to whip off a message, and have someone recieve it. If you need for a ship to disappear without a trace, you can.

I think if you read contemporaneous accounts of Pearl, you'll see that for the first few days the U.S. Navy wasn't sure of the status or location of some ships that were in transit from one harbor to another. (Actually, the Indianapolis was one of those ships.) It's hard for us to believe in these days of instantaneous communication, but that was a different era.

I do know that this policy was changed just before the end of WWII, after the Indianapolis tragedy. Again, it was primarily a problem only when single ships were being reassigned from the command in one harbor to another.

On the evening of December 7, 1941 nervous American gunners shot down some planes from Enterprise because of poor communications.

maestrowork said:

Thanks. My story happened right around Pearl Harbor (although not at Pearl Harbor). So would the ships and the command posts know where the ships were? And would they know if the ship had been attacked and sunk?

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Lots of secure technologies were available at the time (such as Heddy Lamar's frequency hopping radio, which the Film Star invented along with avant garde composer Antheil in the summer of 1941):

Evaine said:

Douglas Reeman wrote a lot of WW2 stories set either on submarines or in warships, often in convoys, which can give an idea of what was used, and how. I went through a phase of reading them, years ago.

The Cruel Sea, by Nicholas Monserrat, (also a film with Jack Hawkins) was also a factually based story of a minesweeper in WW2, the Compass Rose.

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It's a good movie. The Compass Rose was a Flower Class Corvette IIRC.
Or rather the fictional Compass Rose was modeled on what the Flower Class Corvettes were like.

There are plenty of good, semipopular histories of the war that do a good job of describing radio procedures. R. Frank's book on Guadalcanal for example:

(which is cited here:

http://www.npr.org/programs/re/archivesdate/2002/aug/guadalcanal/index.html

maestrowork said:

Would the radio be encrypted?

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Encryption occurred at many different levels. For example during the Fall of 1942, the US could not read the high level Imperial Japanse Navy's codes, but they could read the simpler codes used by the Japanese Harbor master at Truk. So the US could track some IJN ships by associations (call signs, but not decoded messages as signals traveled up and down the transmission stations), some by aircraft transmissions (eg. carrier planes training in the Inland Sea) and some by "safe arrival" signals from the Harbor Master in Truk.

I was a ham radio operator as a kid in the '60s. All my equipment was WW11 military surplus so I have a bit of hands on experience with the antique stuff.

When the war ended there were huge piles of equipment waiting at the docks in Montreal for shipment to Russia. You may recall that they were allies in 1945 but quickly became the enemy and so none of the materiel ever made it out of port. A lot of it ended up in the war surplus shops in Montreal.

The neatest bit of gear I ever had was the complete communication system for a Russian tank (without the tank of course). All the lettering on the control panel was in Cyrilic and it glowed in the dark due to radium paint!

Anyway, there were two bands that it worked on.

One was the low frequency band which was for long distance since the radio waves bounce off the ionosphere.

The other was the VHF (very high frequency) band. That was strictly line of sight.

So if you are at sea I presume back in WWII you coulkd use VHF at least to the horizon.

Admittedly, I never got my grubby kid's hands on any naval stuff though. Just the tank stuff and radio gear from WWII fighter planes.

Does anyone out their remember what a vacuum tube was or what that gear smelled like as it heated up?

Radio Direction finding in WW2 was not as precise as it is now. During the war, you could get it down to a mile or two.

They would not have put men in dinghies with radios to fool the enemy. Where would the radios have come from. Ever see a WW2-era HF transmitter? Regardless of what hollywood shows, it just didn't work like that.

tallus83 said:

Radio Direction finding in WW2 was not as precise as it is now. During the war, you could get it down to a mile or two.

They would not have put men in dinghies with radios to fool the enemy. Where would the radios have come from. Ever see a WW2-era HF transmitter? Regardless of what hollywood shows, it just didn't work like that.

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Not to mention a dingy or even the old style navy cutter (25 ft long and weighing 2000lbs) that they rowed would be bobing all over the place. You need a stable platform for radio direction.

You're right telus, the transmitters were enormous and remember the old power tube in the last stage of those suckers? The size of a four quart milk jug!

On the other hand, the WWII air craft transmitters and receivers that I worked with as a kid were about 12" by 8" by 8". They were state of the art, ennormously expensive when they were first produced and not worth wasting on the Navy!

Most search aircraft and bombers had a VHF set and an HF set. HF was used to send information via coded morse, while the VHF was for air to air conversations.

Basically, fighters were VHF only.

So before somebody says anything about the movie Pearl harbor.

The aircraft conversations from the Doolittle Raid would NOT have been heard at Pearl Harbor. That is just Hollywood BS.

I'm not sure of the US Navy, but I know the Royal Navy would send a message to the Admiralty stating they were under attack and give their position. Radio silence being of no use at that
point.

Also, HF communications will bounce all over the world. While atmospherics can cause problems, it is possible to transmit in London and receive it in the Pacific. That would require a transmitter in the 30KW or more range. Most of Europe can be hit with a 4KW unit from England.

Hope this is of some help.

You can get odd bounces with radio waves. My dad was manning a radio on a battleship and heard the Navajo Code Talkers from a different group of ships that was hundreds of miles away

He didn't speak Navajo, but it sounds enough like the northern Athabaskan languages he was familiar with that he quickly figured out that he was hearing Indians, it was some sort of code because the messages made no sense, and he didn't mention it until long after the war was over.