There is nothing wrong with your method, as far as I can see. You can triangulate any three points on a curved surface and the distances will be consistent with their being on a flat surface. Add a fourth point, and you will immediately tell whether the surface has Euclidean geometry (i.e. is flat) or not.
How the distances could be wrong. Tom Bishop has always wisely insisted that distances given by the establishment are incorrect. Distances and flight times should be the focus of all future FE research.
We do need to be careful just dismissing distances that the establishment give us.
You can get into a 1985 chevy pickup with a purely mechanical odometer and a modern GPS navigational unit.
You can start out at one end of the country, put in a destination for the other end, and clear your trip odometer, and begin a journey.
The GPS accurately adds up all the distances of all the roads, and tells you, how many miles it will be.
Then you drive there, and it's that many miles according to your odometer.
And the establishment cannot possibly be fudging your purely mechanical odometer to match the GPS system.
I've taken cars and odometers apart. There's a cable that is geared to your drive line, which turns a set of gears and little wheels in your odometer housing.
It measures distance plane (lol) and simple.
Same thing for flying small airplanes, as many private pilots use GPS in their small planes.
They are flying straight lines, and the GPS tells them it's so many miles, and they have a windspeed indicator and they know how fast their plane is flying and they can calculate the distance between two points, and GPS works great there too.
So I think we have to realize that GPS distances on land masses work very accurately within that land mass.
However, when we get to going between continents it's harder to prove that the GPSs are telling the correct distance.
We are stuck with the flight times though, a distance between southern continents is so great it would require the planes to fly at over the speed of sound, so I'm not sure how we deal with that.
For example, I added up some flights that I saw happening on flight radar 24.
The following flights connect to form a loop all the way around the earth, as follows:
Start in Sao Paulo, Brazil
Fly to Johannesburg, South Africa
Fly to Perth, Australia
Fly to Melbourne, Australia
Fly to Auckland, New Zealand
Fly to Buenos Aires, Argentina
Then fly to Rio De Janeiro, Brazil where you will be very close to where you started.
That is a path that circumnavigates the earth south of the "equator"
There's probably a better path but these were just flights I saw on the live tracker in one day. I saved screenshots if anyone doubts.
Adding up the official flight distances (which we may not be able to trust) and the official flight times (which we can trust because everybody who flies knows they are pretty accurate on the time because we check our watches at takeoff and landing!) -- anyway, adding up these flights gave about a total alleged circumference of around 20,000 miles, which would mean that all the civilized continents fit inside about a 6500 mile diameter circle on the flat earth.
And I'm inclined to believe the mile distances of those flights in general because they the time they took averaged to around 530mph which is expected for a jetliner.
But one flight I saw was very disturbing, Singapore to Newark 18 hours long and 9500 miles.
How do you fly a 9500 mile flight across a 6500 mile diameter circle? And Newark isn't even near the edge of the circle, and for that matter, neither is Singapore. So that means two points near the middle of the earth are 9500 miles apart, so the disk must be at least 20,000 miles in diameter!
Granted, the jets could be going a bit faster or a bit slower to fudge the calculation to make the distances look different, but ultimately jets have a limited range of speeds.
Most commercial jets today cannot go over the speed of sound, nor can they go below a certain speed, especially at 34k feet, or they'd fall out of the sky.
So we've really got a challenge here, and I'm trying to help prepare us for the work we need to do so we don't think it's easy and end up like TigerDan who thought he could do it then gave up when he realized he had to make his flat earth spherical to make the flights match up.
If we can solve the map we'll have it all solved.