Plain-language answer: Chordal-hop propagation describes long ionospheric paths in which energy travels between ionospheric regions with reduced or no intermediate ground reflection.
Why operators care
Avoiding lossy ground bounces can support unusually long paths, but the mechanism is condition-dependent and hard to prove from one contact.
What to compare on air
Compare path length, signal behavior, propagation conditions, and simultaneous reports before assigning the mechanism.
The common mistake
Labeling every strong long-distance signal a chordal hop.
Forecast boundary
Space-weather indices and propagation models describe probabilities and regional conditions. A usable contact still depends on the exact path, time, frequency, antenna pattern, noise, power, and current observations.
