The Civil Aviation Authority of Singapore (CAAS) informed airlines operating at Changi Airport of airspace closures during the Jubilee Weekend and National Day Parade (NDP) 2015 as early as in January ("23-hour flight delay due to Jubilee celebrations: Qantas"; last Tuesday).
CAAS also reminded airlines on July 29 and Aug 5 to adjust their flight schedules to take the closures of the airspace into account and to adhere to the rescheduled timings.
Additionally, CAAS advised aircraft arriving before and after the airspace closure that air traffic at Changi Airport would be busy and that they should expect delays.
Airlines had, therefore, rescheduled their affected flights well in advance. On Aug 9, some 150 flights were rescheduled, with minimum impact to operations.
The airspace closure period was within what airlines were notified of earlier.
Only four aircraft bound for Singapore had to be diverted to Batam and Johor, as they did not arrive according to their rescheduled timings before the closure of the airspace, and could not hold in the air to wait for the airspace to be reopened.
Singapore air traffic control facilitated all airlines' requests for diversions and returns. With the exception of one aircraft, the diverted aircraft landed in Singapore within four hours of their original rescheduled arrival times.
Director (Air Traffic Services)
Civil Aviation Authority of Singapore