A helicopter of the Republic of Singapore Air Force tows a huge Singapore's national flag during the national day parade rehearsal held in Singapore, July 27, 2019. (Xinhua/Then Chih Wey)

Parachutists of the Singapore Armed Forces' Red Lions participates in the national day parade rehearsal held in Singapore, July 27, 2019. (Xinhua/Then Chih Wey)

A parachutist of the Singapore Armed Forces' Red Lions participates in the national day parade rehearsal held in Singapore, July 27, 2019. (Xinhua/Then Chih Wey)