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Horizon

Season 4, episode 20. This player now records resume state for the active profile so browse, account, and detail pages can bring you back here quickly.

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S4 E20

Air Safety: The Unknown Factor

Horizon investigates air navigation and flight safety.

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Back to series detail

Episode 1: Sons of Cain

Episode 2: When Is a Body Dead? / How to Win Friends and Influence People

Episode 3: How Best to Make a Man / How Best to Make a Scientist

Episode 4: Dynamo - The Life of Michael Faraday

Episode 5: Migraine

Episode 6: How Safe Is Surgery?

Episode 7: Sleep and Dreams

Episode 8: The Shape of War to Come

Episode 9: Memory