In May 2013, a written reply to a question raised in the Singapore Parliament on "defence equipment installed on HDB blocks" got us curious about the type and number of such hardware atop public housing built by Singapore's Housing and Development Board (HDB).
The question and answer is reposted in its entirety below.
Ministry of Defence (MINDEF) website.
Posted: 13 May 2013, 2100 hours (GMT +8)
Written Reply by Minister for Defence Dr Ng Eng Hen to Parliamentary Question on Defence Equipment Installed on HDB Blocks
Assistant Professor Tan Kheng Boon Eugene: To ask the Minister for Defence
(a) whether defence equipment, such as radar, are installed on HDB blocks and, if so, what are the reasons for doing so;
(b) how are public health, safety and security concerns managed and mitigated; and
(c) whether these installations pose an added danger to HDB residents during times of military conflict.
Dr Ng Eng Hen: "There are less than a handful of defence equipment installed on HDB blocks as part of SAF's surveillance network to ensure Singapore's security. These were sited only after all other viable alternatives had been exhausted. These equipment pose no adverse effects on health of individuals as they keep well within international norms and standards required by local agencies. In fact, the measured levels are similar to base stations for mobile phones that have been set up by commercial telcos across the island.
These installations protect all Singaporeans as they serve to prevent attacks on Singapore."
We found that Asst Prof Eugene Tan's family lives in Marine Parade. This could have triggered the question from the Nominated Member of Parliament (NMP) on this somewhat arcane subject as hardware - which this blog believes to be "defence equipment" - was observed on a block of flats in Marine Parade.
His question on public health could have stemmed from worries over long-term health implications having his loved ones in the vicinity of "defence equipment" which appears turned on 24/7.
In the United States, for example, there have been concerns that overhead power lines may have led to a rise in childhood leukemia. Whether living nearby to "defence equipment" (such as radars) in Singapore would result in elevated cancer risks and other health complications would be areas of concern for the layperson.
About Defence Minister Dr Ng Eng Hen's reply:
The pointed questions on 1) public health, safety and security and 2) whether these installations pose a danger to civilians (HDB residents) during a war were only partially answered.
In the opinion of this blog, DM's reply did not address the question "whether these installations pose an added danger to HDB residents during times of military conflict". In simple language: Would the installations, presumably used by the Singapore Armed Forces (SAF), represent a legitimate target under the laws of armed conflict?
In addition, DM's reply that there are "less than a handful" of defence equipment installed on HDB blocks led to speculation over MINDEF/SAF's definition of what constitutes "less than a handful". We set the number at less than five HDB blocks.
The obvious question was where these blocks are located.
We found radars on HDB blocks in Marine Parade and in Woodlands.
* Both radars were installed on the roofs of 25-storey point block HDB flats. These were built before legislation made it compulsory for flats to have a household bomb shelter.
* Radars in Woodlands and Marine Parade are of different types. The one north keeps an eye on Malaysia while the one in Marine Parade scans coastal traffic towards Indonesia's Riau archipelago.
Radar at Block 215 Marsiling Lane, Woodlands - Elta EL/M 2226 ACSR short range radar?
The Woodlands radar has a commanding view of either side of the Causeway road and rail link which connects Singapore with Malaysia. It appears to be sited there to keep an eye on seaborne traffic in the Johor strait.
This apparatus on Block 215 Marsiling Lane is the northernmost radar site on the Singapore mainland.
We are not radar experts but the shape and form of the antenna appears to conform to that of the Israeli Elta EL/M 2226 short range gap-filler radar.
A close look at the infrastructure on the roof indicates that there may be an electro-optical (EO) ball mounted on one corner of the roof. The images you see above were captured from Johor.
Radar along Keppel Road
For the sake of completeness, the survey included commercial premises. This resulted in the addition of a building along Keppel Road to the findings. This radar is of a different type from the arrays seen in Woodlands and Marine Parade and appears to be connected with the control of shipping entering and leaving Singapore harbour.
Radar on HDB Block 14 Marine Terrace - Elta EL/M 2226 ACSR?
The radar on Block 14 Marine Terrace is fitted on the life machinery room of the block of flats, which was built in the 1970s on reclaimed land. The HDB point block has four units on each floor, each with a different facing linked by two lifts in a central lift shaft, for a total of 96 units.
The unknown type of radar comprises two dish arrays stacked one on top of the another. The shape and form of the radar antennae is thought to resemble the extended range variant of the Israeli Elta EL/M2226 Advanced Coastal Surveillance Radar (ACSR). The X-band device is said to be able to track 500 surface contacts simultaneously.
If this is the case, then this would confirm the emitter as "defence equipment" used by the SAF to build up its sea situation picture.
The orientation of surveillance is south-facing, towards Indonesia's Batam and Bintan islands. On the north-facing side, there appear to be baffles behind the radar which screen the emitter from TV and assorted aerials which crown the roof of Block 14.
Sweep rate was observed at around 60 revolutions per minute. At its perch 26-storeys above ground (including the lift machinery room), the radar horizon has an unobstructed view of all coastwise traffic in the Singapore Strait.
As with the arrangement at Marsiling Lane, there appears to be some sort of electro-optic device paired with this radar. This device is backed by the same sort of baffle which screens the device from the radar immmediately behind it.
Some views of the radar antenna are shown below for radar enthusiasts. Please compare and contrast the images with that of the Elta EL/M2226 ACSR.
The addition of "defence equipment" such as radars and EO on civilian buildings may make such property legitimate targets during a war should a belligerent want to knock out the SAF's eyes and ears.
It will be clear that hostile action taken to destroy, degrade or disable the radars will affect residentials not just in the host block, but those hunkered down in apartments in the immediate vicinity who are in the blast radius of ordnance dropped on the radars.
It will be interesting to know what sort of drawer plan MINDEF/SAF have drawn up for a Period of Tension which would ensure the safety and wellbeing of residents who live with a radar over their heads.
Should you know of any other HDB blocks with radars on their roofs, please contact me at firstname.lastname@example.org