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A notable example involves comparing NASA’s spacewalks outside the ISS with Chinese spacewalk footage from the Tiangong space station. Critics have claimed that the Chinese hatch appears "solid" and suggests an underwater setup. However, the presenter notes that the Chinese hatch is visibly a rigid, solid door, which aligns with actual space hardware. Conversely, NASA's hatch appears more flexible, which is explained by it being a thermal cover—used to shield airlocks from thermal extremes during EVAs.
Why do ISS hatches open inward?
Because they are pressurized structures, similar to submarine hatches that open inward due to internal pressure pushing against the door. This design choice is consistent with engineering practices for space stations, not underwater mock-ups.