[existoid]

As none of you yet know, I am a military history buff (in the middle of reading a series of books on the Eastern Theater of WW2 about how the Red Army stopped Hitler).

This thread ( https://forum.tfes.org/index.php?topic=16361.0 ) has been an interesting read as experienced sailors give their thoughts. As I’ve pondered the thread, and the fact that Memorial Day is next Monday, I was inspired to think about how the favored Azimuthal (monopole) map for FET doesn’t comport with my understanding of the Pacific Theater in WW2. So, the first post I’m starting in an upper forum will be thematic!

Summation of Argument
This is going to be a longish post. Bear with me, there are several important points that will follow to reach a coherent conclusion. Skipping to the end to read the conclusion only would be akin to not familiarizing yourself with FET before posting . However, I think it will be useful to summarize my argument so you can follow it as I deep dive the sections:

I.   According to the monopole FE model, distances on the ocean south of the equator are necessarily much longer than on the RE model (lines of longitude get further apart the further south you are traveling).

II.   In the Pacific Theater of WW 2, carrier battles were fought over hundreds of miles and so carrier planes had to successfully navigate across many degrees of latitude and longitude to fight and to safely return to their carriers. To do this, they used plotting charts that required accurate scales for latitude and longitude.

III.   Conclusion: lines of longitude do not get further apart as you go further south of the equator, contrary to the monopole FE map.

I: Longitude and Latitudes South of the equator
According to the monopole FE model, lines of longitude diverge the further south (outward) you go on the surface of the world. And each line of latitude further south is a larger circle than the one before.

You can easily see how this works on this map from the Wiki:
https://wiki.tfes.org/File:Map.png

The angle that the lines of longitude make extending from the north pole is 1 degree each (which is why they’re called “degrees”). From this knowledge, we should be able to determine how much further apart each line makes the more miles it travels south (outward) towards the Antarctica ice wall. Although I cannot do this, because I suck at even elementary geometry.

APPEAL TO MATHY FOLKS: Since the FET model does not dispute that lines of latitude are about 69 miles apart from each other, it would be super awesome if someone could calculate how far apart any two lines of longitude become along each successive line of latitude. Seems like this would be extra-useful in discussing the monopole FE model. (Assuming this hasn’t been done yet – the Wiki does not show this anywhere that I can find).

Whatever the exact distances between longitudes as you get further south, this monopole model of the earth requires very different scales for naval maps south of the equator than north of the equator.

II: Carrier Battles and Aerial Navigation during WW2
There were many naval battles in the Pacific Theater. Among those, there are five major carrier battles. I focus on carrier battles for this discussion because carrier battles involve much greater distances, as a rule, than surface ship only battles. (Although carrier battles can also involve surface ships). This is because carrier fighters such as the Corsair, Wildcat, Hellcat, and the Mitsubishi Zero had ranges of hundreds of miles (some of them well over 1000, like the Zero).

Since carrier battles take place over hundreds of miles, their planes are flying across several degrees of latitude and longitude. In fact, it was very common for the carriers themselves to never even see each other during the entire battle. This was the case for both the first battle (Coral Sea), as well as the most famous one: The Battle of Midway.

The 5 major carrier battles in WW2:
1.   Coral Sea, May 1942 – south of equator
2.   Midway, June 1942 – north of equator
3.   Eastern Solomons, August 1942 - south of equator
4.   Santa Cruz, October 1942 - south of equator
5.   Philippine Sea, June 1944 – north of equator

Two of these, Eastern Solomons and Santa Cruz, were part of the larger land/sea/air battles of the Guadalcanal Campaign that lasted from August 1942 to February 1943. This six month campaign involved more naval battles than all other naval battles of World War 2 put together. It was the most complex and busiest time for naval action in WW2, and perhaps in world history. It involved tens of thousands of soldiers, sailors, pilots, and support personnel. The area of the campaign was very large, encompassing many degrees of latitude and longitude.

And it all happened south of the equator.

For the complex carrier battles to be planned as they were, the sailors of all the ships had to deal with known distances and directions their aircraft and ships must move in relation to each other. Not knowing how far apart different lines of longitude actually were would have created disasters for their battle plans. They would not have worked. But they did.

There was no GPS in WW2. Radar was in its infancy and could not detect over the horizon (this technology wouldn’t exist until after the war). So, finding your enemy in WW2 was done the way it was done in warfare since antiquity: scouting.

In 1942, the typical method for the Japanese was to send scouting plans from their heavy cruisers and carriers in a radial pattern to cover as much area as possible. They would go out several hundred miles along different prescribed routes from their ship, do a “dogleg” of a few dozen miles, and then return back to their ship.

The diagram below is the search pattern undertaken by the Japanese carrier task force in the early morning of June 5, 1942 (battle of Midway). This is north of the equator, as stated above. This is just for illustrative purposes (it’s what I had quickest at hand in my personal military history library). The “dogleg” is the left turn each plane makes. The return paths are not shown.

(See attachment to post)


Notice how they fly across several lines of latitude and longitude on their outbound journey, traveling over 300 (nautical) miles outbound before their doglegs.

What happens when you cannot find your carrier on the way back? It’s highly likely you simply die when you run out of fuel and crash into the ocean. This happened to some.

Before (and sometimes during) any major battle, radio silence was the norm, to avoid detection. Pilots were not allowed to radio their carriers to ask for a position if they can’t find them – as the enemy could easily listen and find their position too. Hiding where you were – and where you were coming from was a vital part of many battle plans (for example, the US surprised the Japanese at Midway by coming from the northwest).

All you had was a knowledge of the route your carrier was supposed to take. Granted, this route can change due to sighting an enemy, making it harder to return. But the planes could see a good 25 miles at their altitudes, so the carriers would have to deviate quite a bit for this to be a problem.

They had to return to their carriers or die. It was literally a matter of life and death.

Navigating with Plotting Boards
In order to avoid death, the pilots needed a way to navigate accurately. One of the primary ways this was done by WW2 pilots was with Plotting Boards.

Here’s a picture of the “Mark 3” plotting board inside an F4F Wildcat cockpit:
https://timeandnavigation.si.edu/multimedia-asset/fm-1-wildcat-cockpit-with-deployed-mark-3-plotting-board

Here’s an instruction manual for using the Mark 3 plotting boards in WW2. I admit I do not understand all of it:
http://fer3.com/arc/imgx/Plotting-board-instructions.pdf


But it is clear that it requires correct scales for longitude and latitude to work properly. Specifically, go to pages 70 and 71 (not of the PDF, but the scanned document). Chapter 18, titled “Converting Minutes of Longitude to Nautical Miles According to Latitude.”  The explanation of how to actually do this is on page 71.

If the monopole FET map were correct, these plotting boards wouldn’t work south of the equator. Pilots using these plotting boards would die virtually every time they used it, unless they lucked out and saw a friendly ship.

III: Conclusion
Battle planning for the three carrier battles in WW 2, the methods for scouting for enemy ships, and all aerial navigation in general worked the same both south and north of the equator. The plotting charts they used required it to be so.

Perhaps you could theoretically have a different plotting board for south of the equator, I don’t know. But I’ve never found anywhere it said that different plotting boards were needed depending on if you were north or south of the equator. Each plane was only fitted with one, regardless of where they were in the Pacific.

WW 2 involved a hundreds of thousands of sailors (and pilots) from two belligerent nations aimed at destroying each other. The US and Japanese had no reason to keep some vast conspiracy about a flat earth secret between each other. By contrast, they had every reason to keep advances in science and technology very secret from each other (and they did). At different points in the war, they had different levels of technological advancement in many areas, including ones critical to naval warfare such as radar.

The only way to understand the Pacific Theater of WW2 is through the lens of a spherical earth in which lines of longitude do not diverge the further south you go. I find no reference to WW2 on this website, so I am hoping this is a valuable contribution to the overall debate.

Thank you for reading.

Fun Historical Aside with no bearing on the FET discussion (i.e., feel free to ignore):
The Battle of the Atlantic was a super important part of the allies winning the war - the battle between allied bombers and destroyers against German uboats. By late 1942, the Germans were sinking the ships and transports the US sent over to Europe faster than we were able to build them (sinkings exceeded shipbuilding by something like 200,000 tons per month!). If this were to keep up, no D-Day would have been possible in 1944, and our invasions of Sicily and Italy in mid-1943 (Operations Husky and Avalanche) would have ended in disaster when we couldn’t re-supply. Luckily, by the end of 1943, due to a comprehensive change in approach by the US navy (involving new tactics, new technology, and even a new organizational outlook), the uboats were on the defensive by the end of 1943, and in 1944 were much less of a problem than in 1942. There were tons and tons and tons of naval actions during these years, involving special routes convoys had to take with precise lengths and time periods to cross areas of the ocean. They definitely knew where they were at all times, and how long things would take. Unfortunately for any FET vs RET discussion, nearly all of this happened north of the equator. So, it’s just a fun historical aside for this post.

[Tom Bishop]

I believe that planes tend to navigate by listening to radio pings from nearby sources to measure distances, rather than the old-timey way.

https://www.wired.com/2010/07/0706aircraft-radio-compass/

July 6, 1920: Pilots Navigate Using AM Radio

__1920: __A U.S. Navy seaplane departs Hampton Roads, Virginia, and heads out over the ocean. Using a new radio compass, the pilots are able to locate and fly directly to a Navy ship nearly 100 miles offshore. It's the first use of radio navigation by an aircraft.

During the post–World War I boom in aviation, pilots navigated primarily the same way drivers did at the time: They followed roads. Using maps, pilots could follow roads – or perhaps rivers or other prominent features – from place to place.

Unfortunately, unless a pilot knew the way, there was no way to directly navigate between two locations. For the Navy, the problem was a bit more difficult. The distance an aircraft could fly was increasing rapidly, and for flying boats in particular, there was now the possibility to fly airplanes to ships far out at sea. But there were no roads for the airplane to follow.

Radio direction finders had been around since the early part of the 20th century. By comparing the signal strength received by a directional antenna as it points in different directions, you can determine the compass bearing of the transmitting source.

To test the viability of using radio navigation in an airplane, the Navy installed a radio laboratory of sorts on board the U.S.S. Ohio which was cruising off the mid-Atlantic coast July 6, 1920. A Curtiss-built Felixstowe F-5-L twin-engine flying boat (of the type pictured above) took off from the Naval Air Station in Hampton Roads, Virginia, with no knowledge of the location of the Ohio other than the fact it was within a 100-mile radius of Norfolk.

After only five minutes in the air, the crew was able to use the on-board receiver with a simple pointer to establish an accurate bearing to the ship. After 90 minutes, the airplane had flown the nearly 100 miles to the Ohio and circled the ship before returning to land.

To find the way back, the crew used a technique that would become standard for decades to come. They simply tuned in a radio station in Norfolk and established a heading using the simple receiver and pointer which was now directing them back to land.

This type of radio direction-finding is still in use today. Many airplanes still carry an Automatic Direction Finder, or ADF, that can establish a bearing to a non-directional beacon, or simply any AM radio station. In less-developed parts of the world, the radio compass or ADF is still widely used.

Eventually, using radio signals for air navigation was refined, and the more-accurate system of directional radio beacons became the preferred navigation system during the second half of the 20th century. These devices can guide an airplane over long distances with much greater precision.

An instrument landing system, or ILS, can also provide very precise guidance over the final few miles of a flight, allowing a pilot to land on the center line of a runway without even seeing the ground.

That one doesn't talk about distances, but that can be done too:

https://en.wikipedia.org/wiki/Radio_navigation

Radio navigation or radionavigation is the application of radio frequencies to determine a position of an object on the Earth.[1][2] Like radiolocation, it is a type of radiodetermination.

The basic principles are measurements from/to electric beacons, especially

Angular directions, e.g. by bearing, radio phases or interferometry,
Distances, e.g. ranging by measurement of time of flight between one transmitter and multiple receivers or vice versa,
Distance differences by measurement of times of arrival of signals from one transmitter to multiple receivers or vice versa
Partly also velocity, e.g. by means of radio Doppler shift.
Combinations of these measurement principles also are important—e.g., many radars measure range and azimuth of a target.

So they wouldn't be relying too much on 'lines of latitude and longitude'.

Those battles also appear to have taken place close to landmasses. It is possible that the distances near the landmasses are correct, but the vast oceans are measured based on theory.

What happens when you cannot find your carrier on the way back? It’s highly likely you simply die when you run out of fuel and crash into the ocean. This happened to some.

It seems that you are admitting that it may have happened.

[existoid]

I believe that planes tend to navigate by listening to radio pings from nearby sources to measure distances, rather than the old-timey way.

https://www.wired.com/2010/07/0706aircraft-radio-compass/

1920 is more than 20 years before the battles in WW2.  And yes, there were many ways of navigating, including by radio.  But carrier planes did NOT use radio to navigate when scouting or fighting enemy fleets.  This is why I specifically mentioned that they imposed radio silence, because that could give away your position to enemy ships. These fleet battles, involving hundreds of carrier based planes, happened over distances of hundreds of miles.

Notice also that the article from Wired that you linked repeats the greatest distance as a mere 100 miles.  This is because, in 1920, the range of planes was much shorter. Flash forward to 1942, the year I wrote about, and planes have ranges more than 10 times that - well over 1000 miles. They are using different methods.

Those battles also appear to have taken place close to landmasses. It is possible that the distances near the landmasses are correct, but the vast oceans are measured based on theory.

Yes, most carrier battles took place near islands and land because most of them were prefaces to land invasions.  But this hardly invalidates my argument because they still take place many degrees of longitude from land AND the carriers are many degrees of longitude from each other, on the open ocean.  If they were not accurately navigating on the open ocean, they would have not found the enemy fleet, and they also would not have been to find their way back across hundreds of miles to their carriers.

These battles took place across literally hundreds of thousands of square miles on the ocean. There is absolutely no way they could have found their way back without accurate navigation. And they did this with plotting boards, using lines of longitude and latitude.

What happens when you cannot find your carrier on the way back? It’s highly likely you simply die when you run out of fuel and crash into the ocean. This happened to some.

It seems that you are admitting that it may have happened.

Of course! I'm explicitly stating that it happened. It didn't "probably" happen. There are known accounts of pilots not finding their carriers and landed in the ocean. In some cases they were found, and in other cases they were lost forever. Heck, there was a US pilot this happened to during the Battle of Midway that was picked up by a Japanese warship!

The reason I mentioned this at all was to point out the stakes for all of these pilots. They absolutely had to navigate properly or they would die.  There wasn't guesswork involved. The distances are too great. And so, the navigational methods were accurate, and they followed principles that only work for the RET model. 

EDIT: To follow up with this last point, if the US and Japanese navies had incorrect plotting boards for these battles south of the equator, then that would mean virtually all of the thousands of pilots and planes used in the Battle of Coral Sea; Battle of Eastern Solomons, and Battle of Santa Cruz would have died in the ocean, because the chances of finding their way back without proper navigation is a zillion to one. But they did find their way back - in fact, fighters would go out from a carrier, dive bomb the enemy fleet, fly back, refuel, and then go back out. They were going out and back more than once in the same battle. Across hundreds of miles, and many degrees of longitude.  This wasn't luck, or "theory" that they used to navigate. It was the plotting boards.

[existoid]

Those battles also appear to have taken place close to landmasses. It is possible that the distances near the landmasses are correct, but the vast oceans are measured based on theory.

Woke up this morning thinking I had mostly repeated myself in responding to this, and I think I have a better way of putting it:

I understand you to mean that the maps of the oceans near landmasses are correct, but that at some unknown distance the maps (based on RE) are wrong, and the distances are much further, once you're far out to sea.  So as long as these WW2 battles are within that unknown distance "close"  to land, maps would work just fine.

The problem here is that they didn't use maps. Their plotting boards show zero land. They are, instead, abstract charts with numbers and lines representing degrees of longitude and latitude. With these plotting charts you can go to any point of longitude and latitude so long as you knew what longitude and latitude you were at takeoff (which they always knew).  So, you could have used these in the middle of the Eurasian landmass and it would work just fine, even if you had no map of the land below, so long as you knew where your end point was supposed to be. 

And this is why it's a problem for the FET monopole map. Here's a sort of simple syllogism of my argument:
1. The lines of longitude south of the equator on FET do not match up at all with the RET. 
2. Plotting boards are based on longitudes as understood in RET. Plotting boards worked.
3. The monopole map must be wrong.