[Tautog’s Sub Corner] Code Breaking 101

Tautog here, again! I’m sorry if you’re tired of seeing my mug, but Morgane’s been busy with the upcoming book releases, and so I’m down here holding the fort instead.

Today I want to talk about something that actually mattered a lot in the early days of the Silent Service. Specifically, the period around 1942 where things were really looking bad. Our story takes place in January of 1942.

The ocean was a pretty big place. How did the US submarines know what to hit, and where?

Well, you really have the Japanese to thank for that. In those early days, the IJN got super careless and started to broadcast announcements on a regular base from their big naval base at Truk. For whatever reason, they not only kept to the same route, but the information would come at noon every day.

Naturally, the submariners wanted to jump on this. Command, however, had other ideas. They were a bit hesitant in letting the submarines attack on the grounds that the Japanese might get suspicious and in turn, change up their codes.

Codebreaking is pretty hard business. So I think I should explain the basics real quick. Coding is substituting a letter, word, number, or concept with something else. This everyone get intuitively. For instance, let’s make a new cipher with s = submarine, u = u-boat, and b = buoyancy.

If I say to you SUBMARINE U-BOAT BUOYANCY you’ll immediately get that I’m really telling you “sub.” I can shift the letters around a bit, and say, s = tautog, u = victory, b = carrier. But even this message here – TAUTOG VICTORY CARRIER – would be easily broken because that’s what cryptologists are trained to do. They can recognize these patterns and try to match it to known linguistic patterns through mathematical analysis.

So, to beat this, we do something called encryption. There are many methods for encryption, but the easiest way to do it is to do something to some numbers. In the previous example, let’s say that we made it so that s = 1, u = 2, and b = 3. We can do something to each number, let’s say, multiple everything by itself.

That way, I can send a code that says 1-4-9, and only if you knew my “decrypt” – that is, the proper mathematical answer to the question would you be able to realize that the message I’m really sending is 1-2-3. Even then, you still need to figure out what “1,” “2,” and “3” are. See how this is a lot more secure?

Now, the Japanese naval code was exceptionally difficult to break. JN-25 is what we call a “superenciphered” code. In order to send or receive anything, you needed three books.

The first book had about thirty-three thousand words and letters that had a random five-digit number next to it. The only thing we know is that all these numbers are divisible by three (just in case there’s an error!)

The second book is a “decode” book. It’s pretty simple. It’s like a phone book where you can look up what the corresponding code is.

Now, you might be thinking. That’s a lot of words, but surely the more common words like Tokyo or Battleship or Fleet would pop up regularly. You’d be right. In order to make it more secure, there’s an encryption book. This book had a page number on each page. On each page there would be several tables. On each one of those tables, they had their own identifier, and within the table there are cells with random five-digit numbers in them.

So, here’s how this is actually going to work.

(Photo take from “A Tale of Two Subs”)

Let’s say I want to send a message. “Tautog is happy.” In the normal code situation, it might look something like 00003-00006-00009. To superencrypt this, I go to that table up there, and pick something random.

Let’s just say that this is page 10. I pick column 0, row 1. It’s 24421. Using a Fibonacci subtraction (where the numbers don’t affect the next column), I subtract this number to my first code, 00003. I get 86682. Moving onto the next word, 00006 (is), I move across the table and subtract 43472, getting 67634. So on and so forth.

Then I can make some sort of a code to tell my guy, you need to go to page 10, find the 3rd table, look at column 0, and start on row 1. So it’d be 10301 or something like that.

So now literally I will send you a garbled list of numbers. 88682-67634-91778-10301. Because you also have an encryption book, you can look it up, do the proper math, and then figure out what I’m communicating. Get it now?

(Side note! We’ve got an even better of this thing called ECM-2. It was never broken, too! But we’ll talk about that some other time. Gah, I’m turning into Morgane with this level of off-topic rambling…)

Now, imagine that you didn’t have either of the books on hand. You had neither the decrypt information nor the actual code.

all you had were numbers.

What’s worse, it’s not like the Japanese language is easy, either. Japanese have four alphabets that they could use. They have kanji, in which a single “sound” can mean a full word. Katakana and hiragana are closer to how we would understand an alphabet, and romaji – the Roman alphabet – is used to actually encrypt and decrypt these messages to begin with.

Think about the brain power it takes to find meaning out of thirty plus thousand individual “words” that are used to transcribe a subtle and complicated language.

Remember that Japanese are missing some sounds, too, so it makes reading doubly difficult. “Langley” is very likely actually transcribed as “Rangrey” if a Japanese speaker was pronouncing it.

Then realize that we not only managed to read bits of it, but we managed to figure out just what it is that the Japanese are trying to do.

Realize that if the codebreakers got it wrong, massive loss of life and material could result. After the success that was Pearl Harbor, the IJN was trying to knock us out of the war. Suppose we get it wrong and we lose the last of our bases in the Pacific.

It’s gonna be a much, much longer war then, isn’t it?

Well, guess what? The codebreakers were very good. I’m going to talk about some of the earlier Silent Service battles in a later post – probably right around the time I finish up the early designs section. But just know that the submariners took the information very seriously, and just as they managed to deliver, so did the Silent Service.

See ya next time!

Silent Service: Early War Reconnaissance

Why even give publicity to trolls and armchair generals? That should have gone into the recycle bin, not a website article.
It’s just encouraging retards to email in the dumb shit. Stop trying to justify Pacific’s universe, and instead tell those goons to fuck off and create their own fanwork which conforms to their ideas.

I totally agree! See, questions like these are much better.

In one of Tautog’s silent corners you mentioned that U.S. Submarines were frequently used for scouting purposes as an actual part of their mission. How did this work? How would a submarine even take this kind of information in the first place?

I’m glad you asked. Let me refer you to a manual I have on hand. While the U.S. Navy was still figuring things out in 1942, you can get an idea of how reconnaissance worked by looking at a manual called “Current Submarine Doctrine.”

(Yeah, creative, I know. This is the Navy, after all!)

According to that manual, which was distributed to all submarine commanders…

Submarines are capable of performing three types of reconnaissance missions.

a). Visual reconnaissance through periscope,

b). Photographic reconnaissance through periscope,

c). Reconnaissance by landing party.

I think this list is pretty self-explanatory, but to elaborate slightly…

At the time, many Japanese fortifications were completely unknown. Some of our intelligence on say, the Carolines or the Marianas have been outdated for at least twenty or so years. So, naturally, it was the submarine’s job to figure out what they had. Shore guns. Harbor defenses. Military installations. Beachheads for amphibious attacks. That sort of thing.

(I also think this answers both of your questions. Submarines literally took pictures, or put guys on shore to take pictures. The commander then wrote down any additional notes that he might have thought would be important, and then ran away to safety.)

Now, you might be thinking. Why not just use air recon? Well, aerial reconnaissance has two problems. First, when you fly a plane over, the enemy know you’re scouting them. Secondly, an airplane is only in the area for limited amounts of time, and you can’t really check the accuracy or the orientation of your charts.

The submarine might be slower, but it can do both.

Now, about the cameras used? Those were jury-rigged. Navy has it on record that the Pompano was the first to run one of these reconnaissance missions, and it just so happens that Cmdr. Parks was an expert photographer. After figuring out just how to find a proper focal point, he managed to rig up a small camera on the scope. Two other boats – the Dolphin and the Tautog – followed.

In those super early days, everyone was still learning. The Pompano herself almost got sunk by none other than the U.S. Navy. While she was swimming along, a PBY patrol bomber saw her, thought she was Japanese, and came over to bomb her at 7 AM in the morning. The Pompano’s crew was rightfully confused, and noted in their report that this must have been from a different squadron than the Oahu-based ones since those weren’t scheduled to take off in this sector until much later.

Then this gem happened.

What happened was that the PBY pilots freaked out and called in help. Hours later, three SBDs flew over from the Enterprise and bombed her again. Lucky for the Pompano (and unlucky for the Enterprise pilots, or maybeI should say, lucky for them, too) she only suffered some mild damage in the form of a leaky tank.

Anyways, despite this, Pompano successfully completed her mission. Now, bear in mind that the quality of the photos might not be very high – they looked probably closer to something like below.

Nonetheless, it was good enough to get the important stuff, and submarines will continue to provide a lot of useful intelligence down the road. Years later, submarine reconnaissance would prove to be vital in places such as Tarawa, where the Nautilus would take pictures that would result in correcting a gigantic compass error from the British charts that we were using at the time.

As for the landing party stuff? I think you’ll wanna hear about some of the actual missions. They’re pretty thrilling. So I’m going to hold off here for now! Thanks for dropping by.

[Historical Inspirations] Historical characters in Pacific

Who’s your favorite USN or WW2 person Morgane? You seem to like submarines a lot, so am I right in guessing Nimitz? Will they show up in Pacific?

Close. I hold a lot of admiration for a lot of our historical figures, and I tend to be more sympathetic than not for those that (I feel) got the short end of the stick – Jack Fletcher is a pretty good example. I also tend to defend (more so due to personal opinion, familial experiences (hard to hate your great uncle’s boss, for instance) or other impressions) individuals that may be controversial such as Mush Morton or Ted Sherman.

The latter I’ll answer first. Historical figures show up as either important background characters (E.G. Dwight Eisenhower, the KOG, and so on) or as “historical characters” in the form of ace fairies. The latter out of this group is infinitely easier for me to write, as according to Pacific lore, they are “locked” in time. That is to say, they possess only the knowledge and the “characteristics” up to that point, and the character is effectively frozen in time. So writing a Fuchida is easy because we know how he was during WW2. Writing the aging Fuchida as he appears, not as a fairy but himself in Pacific, is a bit more difficult.

As for the former group, in terms of background characters, you’ll notice that I tend to currently settle with descriptive elements only. After all, the only way to write them well is to read a lot of autobiographies, and you’ll be surprised to find that not two autobiographies are alike. Eisenhower is a prime example of this. I’ve gone through three separate autobiographies of him and combed his presidential library for personality tidbits before finally creating an “impression” of him as a character that I’d like to use. Each of those literally paint a different picture of the president, and I had to do a lot of thinking to synthesize all of those into one thing.

If I was to speak simply, Eisenhower’s a gentle giant. People trusted him. That was perhaps the more important out of all of his traits, and he took that trust seriously. He’s from a rural background, and reading up his experiences – both how he was raised and his experiences at West Point – convinced me that his folky farm-boy persona is both an act that he cultivates and something that is, well, him.

That being said, Eisenhower had an impeccable eye for policy. He is generally considered to be fairly good as a commanding officer in WW2. In real life he ended the Korean War after five months in his presidency and did not get us into another war. Nobody would know how many American and other lives he would have ultimately saved, but that part was particularly irrelevant when you consider that he was a man who stubbornly refused Congress, his advisors, and the Pentagon’s requests of a pre-emptive nuclear strike on countries such as China.

As such, a lot of the groundworks for how STEC grew in Pacific’s universe appeared because he made sense to me. This was after spending quite a bit of effort in trying to see what subtle tweaks can I make to his presidency to get America in Pacific to where I want – let’s just say that even now in 2017 I am ambivalent about the exact order of the presidents that would appear. This isn’t even about Clinton or Bush or Obama or Trump, but let’s just say that I’ve looked deeply into the timeline of Pacific, and I can totally see an America with no Kennedy or Reagan work.

But if you have to have me pick one historical figure to write that pertains to the USN it might come as a surprise to you.

Due to a series of fortunate incidents, I am happy to say that I’ve read more about this man than a twenty-something should. Read Maury’s profile and you’ll quickly see the connection. To me, Arleigh Burke is basically the ur-example of a brilliant USN Navy Admiral. His actions in both peace and war, from childhood to CNO, exemplifies what the Navy is about.

This is a man who not only innovated our destroyer tactics in WW2, but he helped shape the modern day US Navy, with his focus on carrier aviation, nuclear propulsion, and the Polaris missile. He served for six years as CNO – the longest of anyone to hold that office. But he was far more than just a hotshot DD commander, a capable CNO, or a living legend.

As a person? Burke is integrity personified. His work ethic is legendary, as is his drive and professionalism. He’s got a singleminded devotion to a few things in life – his country, the navy, his wife and little else. He spoke his mind and respected and expected others to do the same. Burke’s language can be surprisingly colorful at times.

It’s no wonder to anyone that he would leave but one word as his epitaph: Sailor.


We’re talking about a man who Secretary Tom Gates ordered to take time off because he was afraid that he would break down due to overwork. Sent to a luxury hotel resort in Virginia, Burke lasted a grand total of two days before fleeing back to Washington. He was just uncomfortable in that environment – after all, you’re talking about an admiral who didn’t golf or gamble (the only sport he was known to enjoy is Navy football which he follows religiously), and who sometimes work so hard that he forgets his own dinner parties.

And accomplished he was. By the end of his second term as CNO, he had not only shaped American policy, but he had ensured America’s future investments. USS Long Beach was nearly finished. The Enterprise – the first nuclear carrier – was almost done as well. His Naval Leadership Program is starting to generate immense amounts of talent. He kept the Navy independent, dampened the massive-retaliation strategy, and gotten a lot of younger officers into places where they could do their jobs.

Then there’s Polaris. You didn’t know that Burke was the one who launched the program, got the money for it, promoted it, and ultimately guided it, right?

But did you know what happened to him?

Burke, I don’t want the United States involved in this.

Kennedy’s angry response to Burke’s suggestions of naval during the Bay of Pigs fiasco. Burke himself was opposed to the invasion plans, and he was briefed at the barest of minimums in which – according to his memoirs – that he did not know even how to offer constructive criticism, so little did he know of the organization.

And so, when the debacle unfolded, Burke offered several ways to turn the battle around. He had units ready – he was opposed to it, but he was determined to salvage a bad situation. Kennedy flippantly blocked him at every turn, concerned as he was about the appearance of things. Burke, ever the consummate professional, only had this to say in response.

Hell, Mr. President, but we ARE involved!

When I read about Burke’s anger, something touched me deeply. Here was a man who will serve the nation faithfully for forty-two years, having survived World War II, the Korean War, and watched the Cold War begin.

He achieved greatness and became an actual living legend, he did so much for his country, and yet his last two years as CNO were spent trying to save the navy he loved so much from meddling bureaucrats and politicians. The air force, which first tried to block the development of Polaris, now wanted to take it over. He and a handful of farsighted individuals tried to warn the US of the extraordinary implications behind the “military reforms” (which, I will remind you, resulted in Vietnam…) but their warnings fell on largely deaf ears.

My impression, from reading the correspondences and the historical sources and hearing about the admiral from those who knew him, was that his last two years in office were distressing. The Bay of Pigs incident deeply affected him. He was tired. He was discouraged. He refused re-appointments and lucrative appointments to other offices and finally retired. In short, it was a tragic and somewhat unfulfilling end to the career of one of the most brilliant naval officers of US history.

You know how I started off on Pacific wanting to do something to “save” America – as I stated in that 2016 piece where I laid out my personal politics? That I wanted to make a stand against historical revisionism and what I saw as the slow degradation of our country?

There are a few individuals in history whose ends I felt were simply not fair. It’s a little like how they scrapped CV-6. It’s just …

It hurts.

I want to see if I can do something to mend that.

There are a handful of key historical figures involved in the Special Task and Evaluation Command, and Arleigh Burke is one of them.

Let’s just say I’m working on how he is portrayed and leave it at that.

[Historical Inspirations] 2017/07/19 – More Midway shenanigans

This should probably be titled “Morgane argues with anons on the internet over history” –

Nah, I’m not really arguing. I am vigorously disagreeing. Also this is about the first time I’ve gotten comments on the IRL history as opposed to Pacific history/lore, so this takes precedent over some of the other comments (just look at how many things I’ve left unanswered from the forums or the channel or email…)

hello. regarding your post on the 19th 2017. you mentioned that the american pilots who flew at midway were greenhorns. while this is a general assumption i can assure you that with some digging this is the complete opposite case.

1: wildcats are in extreme short supply. and escorts were called off in an effort to increase the power of the bombing runs

2: thach’s wildcat flight engaged the zero swarm at a position of energy deficiency. aka, below.

3: 21 F2As were used on midway

it might be noted that of course. all 21 buffalos were smashed (well what did you expect they are like biplanes but worse), thach’s 6 cat flight slaughtered the zeroes with most members never getting the ‘thach weave’ briefing, and all ijn carriers went up in flames. if anything, i would say that the american crew at midway was just about equally skilled as their japanese counterpart. the japanese pilots however, probably didn’t expect wildcats to actually outmatch their zeroes.

I don’t think I can agree with that.

Commissioned officers they might be, but in the winter of 1941, these young brown-shoe officers, and their sometimes even younger backseat gunners and radiomen, for all their daredevil courage and enthusiasm, had nowhere near the length of service, the physical and mental training, or the combat experience of their Japanese counterparts. Nevertheless, in January of 1942, the three American carrier groups, with their embarked aircraft flown by young and untested pilots, were the only offensive weapons Nimitz had to hand, and he planned to use them aggressively. The Kidō Butai was supreme in the Pacific Ocean, but there were other targets of opportunity available to the American brown shoes.

Craig Symond, the Battle of Midway. Considered by many naval enthusiasts to be the best Midway book to come out to date.

I bring up this perspective because it is important to note that both the US and Japan were learning, which pre-empts a common and wrong impression that somehow six months into the Pacific war the US were suddenly Japan’s equal. As much as the US CVs racked up “experience” at Coral Sea, the Japanese CVs were also gaining experience considering that the Kidou Butai has been rampaging throughout the Pacific all the way up to that point as well.

In fact, US CV tactics did not mature prior to Towers/Sherman’s massive falling out. What made US CVs deadly was the doctrine involving the fast carrier task force, and that didn’t come about until 1943.

Other points to consider if you’ve done your digging.

  • Yorktown’s flight group was a patchwork of pilots. Max Leslie’s VB-3 were reinforced from Saratoga, many of whom basically sat around after the Saratoga were torpedoed. Thach’s VF-3 had most of their veteran pilots sent to shore. His replacements includes that from the Ranger and other assorted pilots. Some hadn’t seen a carrier for months. Others haven’t served on one period. What’s more, VF-3’s veteran exec officer was killed a few days before Midway in an accident. Contrast this to the IJN air groups that has been training and fighting with each other since the beginning of the war. The advantage here, loathe as I am to admit it, still go slightly over to the IJN.
  • Hornet’s pilots were completely green. Midway was their first combat. Even neglecting everything else 1/3rd of the US carrier airgroups are complete newbies. This experience is self-evident given the Hornet’s performance at Midway.
  • Enterprise’s flight groups were veteran in that they had experience; this is still 1 on 4. Also, unlike the Yorktown planes, the Enterprise’s attack was less coordinated comparatively. Gray went home without engaging the Japanese, leaving Lindsay to fend for himself.
  • The USMC pilots were a mixed bag. 21 pilots reinforced Midway on May 26th. 17 of those were fresh out of flight school, many with virtually no additional experience. Examples include the after-report from VMSB-241. Take a look yourself.

Emphasis in red, mine.

  • The TBFs from what was supposed to be Hornet’s Torpedo 8 were also green. Haven’t seen combat at all.
  • The 4 Army B-26s couldn’t even find the right course and had to be assisted by a friendly PBY to get to Midway.

You must have a very low opinion of the IJN to think that our guys up there were “just about equally skilled.”

1: wildcats are in extreme short supply. and escorts were called off in an effort to increase the power of the bombing runs

Source? Because I have Fletcher’s logs in front of me right now. He has 18 Wildcats in total on Yorktown. He’s keeping 6 for CAP and 6 for VS-5, which wasn’t launched in that first attack wave. That leaves 6 to go with Thach. Don’t think he called off any escorts there.

2: thach’s wildcat flight engaged the zero swarm at a position of energy deficiency. aka, below.

3: 21 F2As were used on midway

it might be noted that of course. all 21 buffalos were smashed (well what did you expect they are like biplanes but worse), thach’s 6 cat flight slaughtered the zeroes with most members never getting the ‘thach weave’ briefing, and all ijn carriers went up in flames.

You have a weird definition of slaughter. For one thing, our torpedo bombers got slaughtered.

From Thach himself:

“six F4F-4 airplanes cannot prevent 20 or 30 Japanese VF from shooting down our slow torpedo planes.”

Secondly, for our own fighter performance? From Buckmaster, Captain of Yorktown:

“When about 4 miles from the Jap outer screen., which in turn was about 10- miles out from the CV’s, two AA bursts were fired by a Jap ship. These bursts were used evidently to direct the enemy Combat Air Patrol to our planes, for almost immediately afterwards our VT and VF were attacked by about 18-20 Zero fighters. Our VF formed a line astern formation in order to stay together and give the leader an opportunity to turn and fire at the attacking planes. Soon after this the rear fighter was shot down. The formation twisted and turned to prevent the Zeros from getting on their tails and also to obtain firing position. During the engagement our remaining 3 VF were able to shoot down 5 Zeros. The Zeros concentrated most of their attacks on the rear plane, making beam and astern runs and pulling clear after each run.

The two VF planes directly over the torpedo planes were able to furnish considerable support to the VT during the first part of the approach when there were only 4 Zeros attacking. But later they were joined by 6 more Zeros, and the 2 VF were too heavily out-numbered to be of much help. They shot down one Zero and possibly another, and saw one Zero shot down by the TBD rear seat men. Soon thereafter, they became separated from each other and from the torpedo planes. One of these fighters was badly damaged and crash landed on board the Hornet. The 4 remaining planes of the escort group landed on board. They lost one pilot and two planes and shot down 6 and damaged two Zeros in the engagement.”

So let’s break this down using American numbers.

2 VF scored one kill. They were outnumbered so this is par for the course. Thach & friends, 3 planes in all, were able to kill 5 Zeros despite being massively outnumbered. This is impressive, but it’s not anything close to a “slaughter.” You are right to say that the Japanese got a rude awakening. This seems to be the case based on what sources we can access from the Japanese.

However, Thach himself scored 3 out of the 5 kills. So I’d say this is really a case of Thach himself being quite good and the Japanese underestimating their opponents. I’m fairly certain if you cloned four of him and put him in this fight then yes, it might have been something of a slaughter, but as it was it was a good hit on the nose.

Also, on the Buffalo?

The Finns had a 26:1 kill ratio flying those Buffalos. Not saying that they were great airframes, but if you knew how to make ’em work, you can. 😉

if anything, i would say that the american crew at midway was just about equally skilled as their japanese counterpart. the japanese pilots however, probably didn’t expect wildcats to actually outmatch their zeroes.

The Wildcat did not “outmatch” the Zero at Midway. Spruance’s action report reads as follows, which sums up the majority of the feelings on the Wildcat for this battle.

“(k) The performance of our F4F-4 is reported as greatly inferior to the Jap “Zero” fighter. The ammunition supply for 6 guns of our VFs in inadequate. For use against the unprotected “Zero,” 4 machine guns instead of six in our F4F-4’s, with the weight saved used for additional ammunition, merits consideration. A new VF with greater range and maneuverability is required.”

By the way, the Wildcat actually didn’t do too poorly. Postwar assessment showed that it would fight the Zero to more or less parity as we figured out very quickly how to actually fight a Zero. It still managed a 5+ kill ratio in 1942.

Anyways. At the end of the day, vigorous disagreements are what makes things fun. I mean, I do this so that people (myself included) can learn. So I hope you find my opinion – if not my answers – satisfactory. Thanks for dropping by.