I found some info on Sky predicted viewing figures and schedules. Nearly 3 hours coverage for qually sounds a bit excessive.
F1 Show - 290k
Practice - 370k
Qualifying - 1.12m (exclusive) / 420k (shared)
Race - 1.34m (exclusive) / 500k (shared)
Channel will launch around March 9
During all 20 race weeks throughout the 2012 season, the channel will be on-air for 63 hours, with a schedule as follows:
Monday to Thursday: 20:00 - 23:00
Friday – Sunday: 07:00 - 24:00
Race specific coverage will run as detailed below:
Fridays: Practice 1: 2:05 hrs, Practice 2: 1:55 hrs.
Saturdays: Practice 3: 1:30 hrs, Qualifying 2:45 hrs.
Sundays: Live Race action: 4:30 hrs.
Between March 9 and November 30, non-race week F1 coverage will be running for 32 hours each week, transmitting at the following times:
Monday to Thursday: 20:00 – 23:00
Friday: 19:00 – 23:00
Saturday & Sunday: 15:00 – 23:00