user: Question: What date did the episode that was directed by Christian I. Nyby II originally air on?
Columns: ['No. in series', 'Title', 'Directed by', 'Written by', 'Original air date', 'Production code']
Types: ['real', 'text', 'text', 'text', 'text', 'real']
Sample row: [1.0, '"Knight of the Phoenix (Part 1)"', 'Daniel Haller', 'Glen A. Larson', 'September26,1982', 57375.0]
SQL:

assistant: SELECT "Original air date" FROM "Table" WHERE "Directed by" = 'Christian I. Nyby II';