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Flat Earther Admits No Practical Explanation for 12,300 Mile Underwater Sound Transmission

Modern Day Debates · DEBATE: Flat Earth Vs Globe | MCToon Vs Soli · May 22, 2026
Flat Earther Admits No Practical Explanation for 12,300 Mile Underwater Sound Transmission
Modern Day Debates
Modern Day Debates
DEBATE: Flat Earth Vs Globe | MCToon Vs Soli
"The shot heard round the world in 1960, these guys dropped 200 and 300-pound explosive charges detonated just west of Perth. These sounds were detected at Bermuda. 19,820 kilometers away. That is 12,300 miles. That is pretty much half of the globe."
Sully presented the 1960 Heard Island experiment where underwater explosions traveled nearly half the circumference of Earth, expecting it to challenge globe theory. McToon responded that diffraction allows sound to travel such distances on a globe with no problem. Sully offered no flat earth mechanism, instead stating he just wanted the audience to hear McToon's explanation to judge its plausibility themselves.

About this episode

On this episode of Modern Day Debates, host James hosted a contentious flat earth versus globe debate between McToon, an eight-year flat earth debunker who filmed the 24-hour Antarctic sun, and Sully, a TikTok flat earther making his first appearance on the channel. The debate centered on three pre-agreed scientific topics: Coriolis effect, distance measurements on Earth's surface, and sonar propagation. McToon opened by presenting gyroscope measurements showing 10.3 degrees per hour drift at 48 degrees north latitude, closely matching globe predictions, along with laser rangefinder distance measurements from Antarctica and Pensacola Beach that he claimed falsified flat earth distance calculations while confirming globe predictions. Sully dismissed the Antarctic measurements as unverifiable anecdote and focused his case on claims that bathymetric ocean mapping uses flat earth Euclidean geometry before post-processing onto a globe, that microwave transmission models require infinite Earth radius values (effectively flattening the earth), and that aviation treats Earth as flat and stationary. The most heated exchange occurred over an 80-mile LoRaWAN transmission record, with Sully arguing it proved impossible curvature and McToon presenting Navy tropospheric ducting data showing 40% occurrence probability in that region. Sully also presented the 1960 Heard Island experiment where underwater sound traveled 12,300 miles, expecting it to challenge globe theory, but McToon said diffraction easily explains it. McToon repeatedly accused Sully of strawmanning globe predictions, while Sully accused McToon of sophistry and poisoning the well. The debate deteriorated into frequent interruptions and meta-argumentation about debate tactics, with both debaters claiming victory. A post-debate poll allowed the audience to judge who presented more persuasive arguments.

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