Singapore’s military capability is difficult to closely assess, as the country's security is excellent and their defence and procurement policies are not subject to partisan use by political parties. In addition, the nation is well aware that discretion is essential in its strategic circumstances. Posturing would unnecessarily irritate its neighbours, and their governments quietly appreciate Singapore's linkages to the USA as these confirm Washington's strategic interests in the region. So Singapore’s defence forces are somewhat opaque compared to the other first-world western powers.
The way to keep aircraft numbers a genuine secret is to either to place them in remote locations or to store them in a concealed ready reserve while a smaller number are used to train and maintain the skill base of a large number of aircrew. Singapore does both. Many RSAF combat aircraft are located away from Singapore, with some F-15SGs being based in the USA at Mountain Home AFB Idaho with the USAF 428th Fighter Squadron.
The 428th was reactivated in May 2009, specifically as a F-15SG Strike Eagle fighter training squadron.
This was part of the 'Peace Carvin V' program between the USAF and the RSAF. The squadron's mission is to provide advanced weapons and tactics continuation training for RSAF pilots, weapon systems officers, maintenance staff and administration personnel, who are assigned on 24-month rotations.
The skills provided to aircrew include but are not limited to advanced tactics training, dissimilar air combat training, live firing and the full range of integrated exercise activity because the 428th is a USAF unit. It is not advertised how many RSAF F-15SG are based in Idaho and even if it were, the figures are easily manipulated or concealed by a decent disinformation and security plan. In Singapore itself, the RSAF practises good operational security. It is common to observe aircraft with their numbers concealed or even removed entirely from external view. In August 2014 a journalist noticed some F-15SGs with visible numbers, and they indicated that the RSAF had more of them than previously thought - which might also be disinformation. Singapore does maintain war stocks of tanks and other army equipment. These are preserved in dryclad and regularly maintained, while more heavily used examples provide training - but the RSAF is not known to do this with aircraft. What they do with aircraft varies: previous practises include assembling machines from material officially purchased as parts, quietly rebuilding written-off aircraft and other such methods of concealing numbers. They are efficiently secretive, one reason for their close relations with Israeli suppliers who are expert at concealing purchase details, costs and parts holdings.
So are the reports valid? To answer this it is necessary to look at how Singapore purchases strategically critical high-technology equipment. The RSAF in particular has a delicate series of balances to maintain. Its equipment has to be the best in its class yet it also has to be low-risk to acquire, and finally has to be in the numbers Singapore needs while not overly concerning Malaysia and Indonesia. These are contradictory requirements. Under Plan 2030, Singapore intends to acquire F-35s to replace the F-16 and F-15 forces, but to reduce risk and cost these will be purchased after full rate production is well underway. So a further acquisition of F-15SG during the period 2012-14 made sense given that the RSAF F-16 force is also receiving its mid-life upgrade now. The F-16 force has to remain in front¬line capable condition for 10-15 years for this upgrade to be economically sensible, and this accords with known factors under Plan 2030 for these aircraft to be replaced from the late-2020s by F-35s.
By that time the F-35 program will be more mature, most problems will have been resolved and costs will be firm - and probably lower - at that stage of the production cycle. Risk management means that it has always been the Singaporean plan to buy F-35 late. This also indicates a degree of internal consistency in the RSAF purchasing additional F-15SGs - and so does rising regional tension due to Chinese claims and activities in the South China Sea. Such a decision also deals with current and possible future slippage in the F-35 program and (more importantly) reduces the risk to Singapore of unforeseen problems. It also ensures that succession planning is stable, meaning that Singapore does not have to operate three fighter types simultaneously.
This is a change from initial considerations back in the 1990s when the nature of the future combat mix was unclear. What the F-15 did was to provide a multi¬role attack aircraft capable of taking over the F-5 air-to- air role as well as the A-4 strike role - and this realised efficiencies in expenditure and operational support. This is a real change in the thinking of Singaporean force planners and it appears that the delays to the F-35 program drove it. Initial thought was that the F-35 would take over the interceptor role of the F-5 Squadrons, which explains why Singapore maintained a relatively large allotment even after exercising the F-16 and F-15 options. The delay forced a re-evaluation and the RSAF realised that it was no longer be limited to the multirole/strike/intercept concept developed for the A-4, F-5, F-16 force mix. With the F-15SG, the RSAF simply does not need three types.
In the early 2000s the RSAF decided that the much upgraded A-4SU Super Skyhawk fleet could no longer be cost effectively life-extended. Modern multi-role aircraft were being acquired regionally and A-4SU radar cross-section could not be further reduced: the type had reached the limit of its design capability. The Israeli Air Force had passed through this same cycle and advised the RSAF to consider a twin- engine solution to improve survivability. The RSAF considered this and agreed. The finalists were the Boeing F-15 Strike Eagle, the Dassault Rafale and Eurofighter Typhoon. The latter was eliminated due to restricted strike capability and an upgrade schedule unsatisfactory to the SAF and so the F-15 was finally selected: in December 2005 a contract was signed for 12 F-15SG with an option for another eight for a total of 20. The option was then expanded to 12 in October 2007 and exercised for a total of 24 F-15SG.
These aircraft have the serial numbers 05 0001-05 0024. They equip No. 149 ‘Shikra’ Squadron based at Paya Lebar, where, from 5 April 2010, they replaced the F-5S/T Tiger II interceptors. No. 149 Squadron has since earned an enviable reputation with these formidable aircraft.
The RSAF was apparently pleased with the type and also agreed with the views of 149 Squadron's pilots because F-15SG with serial numbers ranging from 05 0025 to 05 0032 were seen at Mountain Home AFB in January and February 2014. This number spread indicates that at least eight more F-15SG have been purchased (five numbers in this range have been confirmed in multiple sources) and Boeing itself has indicated that eight F-15 of unspecified designation were delivered to a customer from 2012. An examination of available public information reveals that South Korea received a number of F-15s during their main procurement cycle to 2012, but it would seem that eight more than the combined South Korean and Singaporean orders have been built. IHS Janes has conducted a detailed examination of this event, and their analysis leaves little doubt that the RSAF currently owns 32 F-15SG, just enough for two Squadrons with a very small attrition reserve.
There is unconfirmed reporting of a further attrition reserve buy, but there is no firm information to move this into the realm of fact. Indeed, such a purchase could even be concealed in a combined upgrade/spare parts acquisition, although it would be an expensive option to do so. In response to IHS Janes questions, a Singapore Ministry of Defence spokesman simply noted that ‘The Singapore Armed Forces bases our procurement on the assessed long¬term defence needs, and the RSAF has purchased sufficient F-15SGs to meet our defence requirements.’ This statement is both factual and confirmation-free, even the implication that no more F-15SG will be acquired cannot be read into it.
Janes has speculated that a final buy number may be 40 aircraft but as yet there is no evidence to support this speculation. That said, such a number makes a great deal of sense in terms of two operational Squadrons with a good reserve of aircraft for training and combat attrition. It makes even more sense when the length of service is taken into account as the RSAF moves towards operating two types of fighter-strike aircraft, as F-15 production is probably entering its final years and the F-15SG will be in service well into the 2030s. The F-15 is a design approaching 40 years old and has been in production for three decades, with over 1,500 delivered to the USA, Israel, Korea, Japan, Saudi Arabia and Singapore. The twin-seat Strike Eagle variants vary widely and are in service with the USA (F-15E), Israel (F-151), Korea (F-15K), Saudi Arabia (F-15S) and Singapore (F-15SG), so supportability of the type over the life of the RSAF F-15 fleet is unquestionable.
It is assessed that the RSAF final number for this type is 44-48 aircraft, enough for two Squadrons with a reserve large enough to keep airframe hours relatively low. This would give the opportunity to extend the life of type if necessary and also take much of the risk out of the F-15SG replacement project which must start by the late 2020s.
The F-15SG is an advanced and upgraded variant of the USAF F-15E Strike Eagle, possessing enhancements, which make these the world’s most potent variants. Most notable is that they have the F110-GE-129C engine, which delivers more thrust than the Pratt and Whitney F100 engines which power most F-15 and F-16 fighters (including the RSAF F-16 fleet). Aside from the usual reliability and maintenance improvements a newer-generation engine brings, this means that a major fault with one engine type cannot ground the entire RSAF fighter force. Again, this is a risk-mitigation factor too often ignored in assessments of Singaporean planning.
The standard radar fit for most F-15s is the APG-70: with the F-15SG the RSAF became the second operator of the AN/APG-63v3 AESA radar, an electronically scanning array radar with a 100-200% range advantage over the APG-70. The radar is also harder to counter-detect as it uses agile beam technology: it is currently the most advanced radar used by any Strike Eagle variant. Other advantages include higher reliability, lower maintenance costs and modular software and hardware updates which permit improved operational flexibility. The APG-63v3 uses line replaceable unit modules. These are simply swapped out at Squadron maintenance level and the modules sent to depot level for repair or upgrade: new software loadouts are pre-integrated in this operating model and the normal problem of depot level maintenance of the modules (the depots can be at great physical remove from the Squadrons) is simply not an issue in Singapore. Overall the complexity of integrating improved electronic warfare capability or improved-bandwidth communications is drastically reduced by this technology.
The F-15SG is a strike aircraft, and so it must have the terrain-following capability of the APG-63v3 and a good reconnaissance and bomb damage assessment capability. This is provided by the Lockheed-Martin Sniper Advanced Targeting Pod (Sniper ATP) which with the addition of the USAF B-52 fleet in July 2013 is now operational across the entire USAF strike platform range. The Sniper ATP imaging systems are full day-night capable in visual and thermal spectrums and have full geo-location capability to provide tactical data to all GPS-guided weapons in US inventory. The imaging is a high-resolution third-generation FLIR and the Sniper ATP has a dual-mode laser, charge-coupled device television, a laser spot tracker and a laser marker to support existing and future laser-guided munitions. The F-15SG also has the advanced Tiger Eyes forward-looking infrared systems for targeting and navigation, and an Infrared Search and Track (IRST) system for passive air-to-air detection.
In terms of avionics the F-15SG has two notable systems, the first is the Boeing Joint Flelmet Mounted Cueing System (JHMCS); this type of system is now standard in modern fighters and strike aircraft. It ensures that critical tactical information (especially targeting cues) is visible to the pilot no matter where he is physically looking so he can keep his attention outside the cockpit as much as possible. JHMCS also permits the pilot to aim the radar, off-bore air-to-air missile seeker heads, infrared sensors and even air-to-ground weapons by observing and designating the target through the helmet's visor and enabling switches on the flight control column. Link-16 capability is provided by a MIDS-LVT link 16 system with embedded modules provide communications security and TACAN. The system passes tactical information obtained by any Link-16 equipped fighters, AEW&C aircraft, ground-based system or warship to all other equipped units via encrypted radio, with seamless matching of tactical symbology, for unidentified, neutral, hostile and friendly units.
Finally, the RSAF F-15SG force is bound to have surprises in its aircraft systems, especially the ECM suite. Singapore works in close partnership with Israel as both have a similar strategic framework, security concerns, and lack of operational depth. Their cooperation extends to shared fundamental concepts of defence and they have long cooperated on development of some systems including electronic warfare, encryption and countermeasures. As mentioned at the beginning of this article, Singaporean security is robust, so any details of Singaporean-lsraeli capabilities and systems fitted to the F-15SG fleet will not be obtainable. All that can be stated is that they are certainly there.
The RSAF’s move to a two-type fleet is heavily dependent on the F-15SG force. Some further expansion of numbers can be expected and the capability of the type will continue to improve. However, an exact assessment of the capability of the F-15SG is not possible due to the excellent operational security of the forces of the Republic of Singapore.
Buying planes is a wasteful exercise because Spore already has the strongest air force in the regime. All our neighbours are spending their money to improve the lives of their citizens. While the PAP is busy making it harder.
