Night flight restrictions
Night period and night quota period
night period 2300 – 0700 hours during which period the noisiest types of aircraft classified QC/8 and QC/16 may not be scheduled to land or take-off. From 2330 to 0600 aircraft movements are restricted by movements limits with noise quotas These are set for each season.
Movements limits and noise quotas at Heathrow
The summer season is the period of British Summer Time in any one year winter season period between the end of British Summer Time in one year and the start of British Summer Time in the next. The change to British Summer Time occurs at 0100 Greenwich Mean Time (Universal Co-ordinated Time).