user: Question: When  Roy Richardson 476cc Aermacchi is the rider what is the time for saturday august 9th?
Columns: ['Rank', 'Rider', 'Mon 24 Aug', 'Tues 25 Aug', 'Wed 26 Aug', 'Thurs 27 Aug', 'Fri 28 Aug', 'Sat 29 Aug']
Types: ['real', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'Ryan Farquhar 500cc Paton', "20' 25.40 110.844mph", '—— No Time', 'Untimed Practice', 'Cancelled No Time', '—— No Time', '—— No Time']
SQL:

assistant: SELECT "Sat 29 Aug" FROM "Table" WHERE "Rider" = 'Roy Richardson 476cc Aermacchi';