NASA and military saying it's flat and motionless, because their supercomputers can't handle it, even your smartphone gaming figures have a more complex shapes than a ball.
Propagation of Electromagnetic Fields Over Flat Earth

Propagation of Electromagnetic Fields Over Flat Earth
https://apps.dtic.mil/dtic/tr/fulltext/u2/a389123.pdf

page 9: based upon the signal having a single bounce on a flat Earth
https://apps.dtic.mil/sti/pdfs/ADA507627.pdf

page 1:
transmission loss over flat earth
https://apps.dtic.mil/sti/pdfs/ADA383456.pdf

http://www.arl.army.mil/arlreports/2009/ARL-TR-4998.pdf

page 1:
Trajectoryof Spinning Projectiles These equations assume a flat Earth.
https://apps.dtic.mil/dtic/tr/fulltext/u2/a519118.pdf

page 2:
These equations assume a flat Earth
https://apps.dtic.mil/dtic/tr/fulltext/u2/a553573.pdf

page 216:
"assuming a flat Earth"
http://tycho.usno.navy.mil/ptti/2007papers/paper21.pdf

Page 1:
so that a flat-earth approximation provides the best estimate
https://apps.dtic.mil/sti/pdfs/ADA387936.pdf

Page 39:
model works over a flat earth
https://apps.dtic.mil/dtic/tr/fulltext/u2/a410145.pdf

page 9:
input to a flat earth
https://apps.dtic.mil/sti/pdfs/ADA414792.pdf

page 3:
The first is the Earth-fixed coordinate system, which is fixed to the Earth with a flat Earth assumption.
https://apps.dtic.mil/dtic/tr/fulltext/u2/a527621.pdf

page: 1
flat earth approximation provides the best estimate
https://apps.dtic.mil/dtic/tr/fulltext/u2/a406615.pdf

page 32:
This model works well over a flat-earth
https://apps.dtic.mil/dtic/tr/fulltext/u2/a379288.pdf

monopulse radar over a flat earth
https://apps.dtic.mil/sti/citations/ADA274914

page 168:
equations of flat-earth trigonometry.
https://www.wsmr.army.mil/RCCsite/Documents/106_Previous_Ver...
https://www.wsmr.army.mil/RCCsite/Documents/106_Previous_Ver...

Monopole Elemnwnf on Disk Ground Plane above Flat Earth
https://apps.dtic.mil/dtic/tr/fulltext/u2/a257911.pdf

page 8:
The Earth is flat and nonrotating.
http://www.navair.navy.mil/nawcwd/command/counsel/ReadingRoo...

page 2:
"In this paper, the rigid body equations of motion over a flat
non-rotating earth "
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/200700...

page 32:
"Lastly, the equations of motion for the zeroth-order problem of flight in a vacuum over a flat Earth are presented."
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/199400...

https://www.nasa.gov/centers/dryden/pdf/88507main_H-2179.pdf

page 14:
(2) A flat, nonrotating earth
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/197100...

page 8:
the missile position in space is computed relative to a flat nonrotating earth.
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/200400...

page:12
"aircraft flying in a stationary atmosphere over flat nonrotating earth"
https://www.nasa.gov/centers/dryden/pdf/88072main_H-1259.pdf

page 108:
aircraft flying over flat, nonrotating earth
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/198900...

page 126:
"The nonlinear equations of motion used are six-degree-of-freedom equations
sith stationary atmosphere and flat, nonrotating earth"
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/198900...

page 2:
"The method is limited, however, to application where a flat, nonrotating earth"
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/197200...

page 11:
"The nonlinear equations of motion used in this model are general six-degree-of-freedom equations representing the flight dynamics of a rigid aircraft flying in a stationary atmosphere over a flat nonrotating earth"
https://www.nasa.gov/centers/dryden/pdf/88248main_H-1777.pdf

page14:
a) The earth is flat and non-rotating.

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/197900...

page 25:
The helicopter equations of motion are given in body axes with rerpect to
a flat, nonrotating Earth.
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/198100...

page 13:
A model frequently used is that of a flat, nonrotating earth.
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/196500...

page 19:
These equations assume a rigid vehicle and a flat, nonrotating Earth.
https://www.nasa.gov/centers/dryden/pdf/88733main_H-2465.pdf

page 9:
For aircraft problems, the state and measurement models together
represent the kinematics of a rigid body for
describing motion over a flat, nonrotating Earth
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/198800...

page2:
In our minimum time-to-climb problem, the aircraft is modeled as a point mass and the flight trajectory is strictly
confined in a vertical plane on a non-rotating, flat earth.
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/200600...

page 8:
All models are flat earth models with stations assumed to be at the earth’s surface.
https://pubs.usgs.gov/of/2002/0171/pdf/of02-171.pdf

page 3:
the program assumes a flat earth
ftp://ftp.ngdc.noaa.gov/hazards/publications/Wdcse-35.pdf

page 1:
a flat earth can be assumed
https://www.maricopa.gov/DocumentCenter/View/658/SRPMIC-Proj...

page 3:
Calculations for a Flat Earth -Ionosphere Waveguide
https://www.gpo.gov/fdsys/pkg/GOVPUB-C13-4647e5540c69c7ae371...

Location data are then fed into a flat-earth model
https://str.llnl.gov/str/Oct06/pdfs/10_06.1.pdf

assumed to be an indentation in a flat earth's crust
https://pubs.usgs.gov/bul/1166a/report.pdf

oscillating magnetic dipole over a continuously stratified flat earth is considered.
https://pubs.usgs.gov/bul/1166c/report.pdf

Page 20 “Flat Earth”
https://www.cia.gov/library/readingroom/docs/CIA-RDP86-00513...

page 3
"assuming a flatearth"
http://a2srl.engin.umich.edu/wp-content/uploads/sites/321/20...

page 3:
"dynamic equations based on the flat non-rotating earth"
https://journals.sagepub.com/doi/pdf/10.1177/168781401879912...

These equations assume a flat Earth.
https://apps.dtic.mil/sti/pdfs/ADA519118.pdf