SINGAPORE, Nov 28 ― From "unidentified” aircraft to planes that deviate from flight plans, a taskforce under the Republic of Singapore Air Force (RSAF) deals with more than 350 such suspicious air threats involving civilian aircraft leaving, entering or flying near Singapore every year.

The Air Defence Task Force also keeps close watch on developments overseas, including terror attacks and alerts, and steps up measures where necessary ― threats that these days may emerge over social media, shared Brigadier-General (BG) Tan Chee Wee, commander of the Air Defence Task Force, on the sidelines of the taskforce’s biannual exercise today.

Exercise Vigilant Shield saw RSAF fighter jets simulate intercepting and escorting a commercial aircraft suspected to be hijacked to Changi Airport.

Speaking to the media, BG Tan said the RSAF takes air threats issued through social media channels, including bomb threats, "quite seriously”, although these are not as prevalent as information it detects from "day-to-day surveillance”.

If there is a lot of uncertainty over the veracity of such threats, the RSAF would typically adopt the "more precautionary” position by heightening its posture, said BG Tan, without elaborating.

He noted that in this "very connected” era, a great deal of information may not originate from traditional channels and the RSAF depends on other government and security agencies as well as airlines for their input. 

Other suspicious air threats include unidentified aircraft on which information such as their destinations or call signs, which identify aircraft, may not be available, and deviations from flight plans, which the RSAF probes "on a daily basis”, said BG Tan, who also helms the RSAF’s air defence operations command.

Most of the time, such aircraft comply, but "occasionally they don’t”. "If the investigation doesn’t give us greater clarity over the intent of such aircraft, then you’ll see us responding”, he said.

In some cases, this involves scrambling the RSAF’s fighter jets to intercept and interrogate the aircraft to ensure that it does not pose a danger to the Republic.

The last time the RSAF’s fighter jets were scrambled in response to an air threat was in January 2008, when a Cessna 208 light aircraft without an approved flight plan had veered into Singapore airspace.  

The RSAF deployed two fighter jets to intercept the aircraft, which was escorted to Changi Airport. Its Australian pilot was subsequently fined S$5,000 (RM15,602) for flying without an airworthiness certificate.

Set up in 2010, the Air Defence Task Force works with other Singapore Armed Forces task forces, including the Maritime Security Task Force, and government agencies like the Civil Aviation Authority of Singapore (CAAS) to respond to potential air threats round the clock.

For example, when an aircraft deviates from its flight path, the task force works with CAAS and the SPF to coordinate a response. Apart from scrambling fighter aircraft, ground-based air defence units, among other assets, would also be activated to be on high alert, and the task force works with CAAS to clear the surrounding airspace of civilian air traffic.

When situations call for fighter jets to be scrambled — which can be done within minutes — the warplanes fly close to the aircraft, at a distance of no less than 660 feet, to check if a third party has taken over the controls in the cockpit, for instance.

If pilots repeatedly ignore instructions, the RSAF will turn to standard operating procedures in accordance with international law. After interception, the fighter jets will escort the aircraft to Changi Airport, where it is cordoned off by the SPF.

For the first time, this year’s exercise featured the KC-135 tanker plane and F-15SG fighter jets.  The inaugural exercise in 2014, which was not open to media coverage, had involved a Fokker-50 maritime patrol plane and F-16 fighter aircraft.

Besides the exercise, meetings are held every six months with agencies like the CAAS and SPF to ascertain if processes and plans are "robust enough” to deal with such air threats, said BG Tan. ― TODAY