A warning siren is sounded. Four F-15SG and F-16C fighter jets roar into action and take off from the tarmac to intercept a "hostile" aircraft intruding into Singapore airspace.
The action is called a "fighter scramble", in which military aircraft are activated and airborne within minutes to react to an immediate threat. It forms part of a 30- minute aerial display at the Republic of Singapore Air Force (RSAF) Open House, which is being held at Paya Lebar Air Base over four days from today. It is open to the public over the weekend. Today and tomorrow are only for organised visits.
Last held five years ago, in 2011, the RSAF Open House promises to be "abuzz with fun-filled activities" while showcasing the air force's operational capabilities, the Ministry of Defence said.
Colonel Randy Ong, deputy chairman of the RSAF Open House organising committee, said:"Five years is not a short time. A lot of things have evolved - our operations, our capabilities and how the third-generation RSAF has evolved...
"What we want is to show the public what exactly the RSAF is capable of now and what our people are able to do to ensure mission success."
The aerial display, which also features the AH-64D Apache attack helicopters, is held twice a day - at 10.30am and 2.30pm on Saturday, and at 11.30am and 4.30pm on Sunday.
Visitors who succeeded in securing an aircraft ride ticket through the online ballot which closed last Friday will get to see the Singapore skyline from above in a 20-minute joyride in one of four aircraft, including the CH-47 Chinook helicopter, which is typically used for transporting troops and equipment and also for medical evacuation, disaster relief and search and rescue.
On the ground, more than 20 types of aircraft and weapon systems are on static display. Visitors can get up close to these RSAF assets, and even climb into the cockpit of the iconic Black Knight F-16C fighter jet with its red and white paint scheme. The Black Knights are the RSAF's aerobatics team.
Inside an interactive exhibition hall, display panels and videos tell stories of the air force and its airmen and women. There are also simulators for visitors who want to experience flying an F-16 aircraft or an unmanned aerial vehicle.
About 800 RSAF personnel are involved in the open house.
Preparations began about nine months ago.
Captain Nah Jinping is one of two female fighter pilots who is involved in the aerial display.
The 29-year-old, who has been serving in the RSAF for six years, said: "There are a lot of moving pieces in the aerial display - from ground troops to air units. The difficulty comes in the coordination and the adherence to the stipulated timing so that we will be on target every single time."
Third Sergeant Alvindev Singh, 26, a full-time national serviceman and an air force technician who is part of the fighter scramble, said: "In 2011, I was there (at the open house) as part of the audience. I never dreamed that I would be representing my squadron today. I'm grateful and honoured."
Some 150,000 visitors are expected over the four days. Entry is from 9am to 6pm and admission is free.