Successfully diverted the threat from its original subject, where no flat earth believer dares to commit to a straight answer because obviously, all the people that live between the Tropic of Cancer and the Tropic of Capricorn are in on the conspiracy ... because all of them observe the sun going in a straight line, east to west, during a culmination.
The sun NEVER "goes" in a straight line.
I note your emphasis on 'goes'. Maybe the use of the term 'appears to travel' would be more acceptable?
In any case, if you're on the equator during an equinox, the sun 'appears to travel' in a completely straight line, from the time it first appears in the morning, through till midday when the sun is directly overhead, until evening when the sun is no longer visible. So to simplify, the sun 'appears to travel' in a completely straight line the whole time that the sun is visible, which will be very close to a 12 hour period.
But according to flat earth theory, the sun can NEVER be observed to 'appear to travel' in a completely straight line, because the sun in transcribing a complete circle over the earth's surface within a 24 hour period, and there is NO part of a circular path that is straight.
Not one flat earther on this forum, has managed to explain why the sun 'appears to travel' in a completely straight line, when in fact, the sun should ALWAYS 'appear to travel' in a curved and circular path.
As I have mentioned previously in a recent post, the upcoming equinox on the 23rd of September will be an excellent opportunity for the flat search society hierarchy to conduct a trip to an equatorial location, and verify one way or the other if the flat earth theory is correct or not.
The results will be conclusive, with the observation of the sun 'appearing to move' in a completely straight line throughout the day, confirming the round earth model, and conversely, the observation of the sun 'appearing to move' in a curved path will confirm the flat earth model.
Here is one of the few conclusive 'experiments' available to the flat earthers to prove beyond all doubt what so ever, that the round earth model is flawed, so of course the hierarchy of the flat earth movement will conduct this visit to the equator on the 23rd of September. Would you be surprised and disappointed if this visit did not take place, a visit that will be ground breaking in favor of the flat earth theory?