Introduction

Security agencies in Singapore need to continually guard against threats to Singapore's air and sea space. In recent years, our agencies have put in place robust surveillance and early warning systems to guard against aerial and maritime threats. However, these existing systems are facing increasing constraints, mainly due to the construction of taller buildings which prevent the systems from establishing a clear line of sight.

The aerostat that the SAF intends to deploy will be a tethered balloon system with 24/7 low-level radar coverage. It will be deployed sufficiently high enough so as to have a clear line of sight over Singapore's air and sea space, and will complement the SAF's suite of sensors to identify potential aerial and maritime threats early for timely and decisive response to safeguard Singapore's peace and security.

Aerostats have been used by different agencies in the world since the 1980s for functions such as early warning and radio re-broadcast. There have been significant developments in aerostats in the past decades, particularly in terms of reliability and safety. Norms and regulations have also been established to govern their safe operation. Currently, a number of security agencies, such as the US Customs and Border Protection Agency, use aerostats to meet their operational requirements.

Quick Facts about the Aerostat System

Safety Measures

The Republic of Singapore Air Force (RSAF) has put in place strong safety procedures that are in line with regulations developed by the US Federal Aviation Authority for the operations of the aerostat system. In addition, the RSAF has been working with the Civil Aviation Authority of Singapore to plan the safe operations of the system in Singapore's congested airspace, and safety procedures such as issuing Notice-to-Airmen to inform aviators of the aerostat's presence. Lightning protection certified to the Society of Automotive Engineer Aerospace Recommended Practice 5412A standards, operating procedures and emergency-handling procedures have also been put in place to ensure the safety of the aerostat system's operations. Preventive measures, such as proper training and regular maintenance, have also been established to minimise risk. 

The radiation level emitted by the radar on board the aerostat is as safe as that of mobile phones, and has been certified in accordance with IEEE C95.1-2005 standards (i.e., that emissions are within safe limits to the population). This is the same standard applied to certify the safety of mobile phones, microwave ovens and MRI scanners.

The aerostat will be secured to the ground mooring station through winch lines and a tether built to withstand strong winds and lightning strikes. The tether is made of Kevlar, and is by far the strongest in its class.