I believe some flat earths think that the vast majority of people who work in their fields as professionals aren't in on the conspiracy, for example all of the employees of space agencies who work as engineers, scientists and such are unaware they're being fooled. I personally think if a small group of people on the internet who aren't experts in those fields have 'figured it out', I'm surprised the actual professionals haven't yet. I wonder how highly educated rocket engineers and physicists haven't managed to uncover it yet?
Qualified surveyors use plane survey methods techniques on areas up to around 100 square miles - 250 km square . This is because no curvature can be found over that area that falls outside of instrument error limits .
In order to fit plane survey onto a sphere , geodesic survey , then spherical trig is applied to plane survey results to produce the globe . All easy to check online , I prefer the old text books myself .
Most geodesic survey work is done these days with the aid of GPS satellites.
Nasa uses geocentric coordinate systems in all it's rocket launches . Again easy to check . Look up launch characteristics for various satellites .These involve a non rotating flat earth coordinate system.
https://steemit.com/flat/@slopetester/15-nasa-research-papers-that-admit-flat-and-nonrotating
Mainly aircraft referred to in that link .
chrome-extension://oemmndcbldboiebfnladdacbdfmadadm/https://apps.dtic.mil/dtic/tr/fulltext/u2/a069296.pdf
This one involves rocket launch and orbital trajectory . A long technical read but it's interesting to read that a launch path up to 500 nautical miles is treated with the same non rotating flat earth system , and that coriolis effect is negligible in the equations.
Nasa seems to use this geocentric non rotating flat earth rather consistently - because it works I think . Why use it otherwise ?
Couple of things about this. So flat earthers think that NASA is stating quite publicly that the earth is actually flat and stationary and all the while they claim NASA are liars. Strange irony in there.
This issue has come up many times. take one of the papers from that FE site your reference, regarding the SR-71. In it, it states, which is similar to the other papers cited:
"DIGITAL PERFORMANCE SIMULATION DESCRIPTION
Maneuver options include constant Mach and airspeed climbs, level accelerations, and constant g pushovers or pull-ups...
The DPS equations of motion use four assumptions that simplify the program while maintaining its fidelity for most maneuvers and applications:
point-mass modeling, nonturbulent atmosphere, zero side forces, and a nonrotating Earth. The primary advantages of using the DPS over a piloted real-time simulator are that it is much easier to modify the aerodynamic and propulsion data tables, and the DPS easily allows back-to-back comparisons of vehicle performance using a maneuver flown exactly the same in each case de- spite a varying vehicle configuration."
The maneuvers being modeled have nothing to do with the shape of the earth, earth's orbit around the sun, the moon's orbit around earth, etc., Much like they also exclude from the model atmospheric turbulence and side forces. By your argument NASA is also claiming there is no such thing as wind.
It just makes for cleaner, faster, easier modeling to not include things that aren't relevant to the effort being examined.