SINGAPORE - Using smoke trails from their F-16s, two military pilots will shape a heart in the sky on Aug 9, declaring love for Singapore on its 53rd birthday.
The manouevre is part of a display that the Republic of Singapore Air Force will be putting up for this year's celebration in Marina Bay.
A total of 26 aircraft, including helicopters, fighter jets and transport planes, will take part in the show - the biggest air force contingent to fly over Marina Bay.
They will perform the traditional state flag flypast, as well as manouevres and formations like bomb burst and diamond.
On the formations, air participation committee chairman Low Say Sim said: "Everything is down to seconds."
"A lot of coordination is needed between teams," added Colonel Low, 48.
Major Lloyd Lin, 34, one of the two pilots involved in the heart-shape manouevre, said that coordination is his biggest challenge.
"Both (pilots') pacing and cadence must be correct," said Maj Lin, adding that he has been practising weekly for the past two and a half months.
The last time the air force performed a similar manoeuvre was in 2008 when the Black Knights, its aerobatics team, drew a heart in the sky.
Besides the two F-16s, an F-15 jet, painted blue as part of the air force's 50th birthday celebration later this year, will round up the aerial performance. It will perform a G-force turn ending in a vertical climb to 8,000 ft.
The airforce will also be saluting the nation in a bomb burst, which will see pilots fanning out in a uniformed fashion. The salute will take place right after the state flag flypast.
One of the six pilots in the bomb burst, Major (NS) Freddie Lim-Ng, said that he and his colleagues are in the difficult process of perfecting the salute.
"Imagine flooring the accelerator with another car beside you while trying to maintain the same position as he is," he said.
"Every small, little minute difference will be amplified (in front of the audience)... so we are still working on it," he added, noting that the planes will be moving from 360 knots to 450 knots (667kmh to 833 kmh).
Getting the symmetry of the fan right will be crucial or the shape will look lopsided, he added.
"So we have to keep practising," said Maj (NS) Lim-Ng, who works as a flight simulator instructor and is a father of two.
Lieutenant-Colonel Benny Lui, the flypast marshall, said factors such as the nearby skyscrapers in Marina Bay, the different speeds of the aircraft and the best altitudes to display the aircraft were considered when coming up with the formation designs for the entire performance.
"If you put the helicopters way up high, you won't hear or see anything," LTC Lui said.
For now, inclement weather is his biggest bugbear, given the rain in recent days.
"It's a matter of (the air force's) visibility during the show versus safety, and we always have safety as the utmost consideration," he added.
Correction note: This article has been edited for clarity.