Procurement and Material Management - DEFENCE MANAGEMENT JOURNAL, December 2004

Protecting our aircraft

Rod Powell, from Wallop Defence Systems Ltd, considers the value of flares in protecting aircraft on missions.

In the 1960s, it was only the V-bombers, in the 1970s, Phantoms and Buccaneers also had them, followed by both Tornado variants in the 80s and 90s. Today, Hercules, Nimrods and virtually all front line helicopters are protected by them. The ubiquitous Infra-Red Counter-measures (IRCM) decoy flare is over 40 years old. Why has this small pellet of chemical compound, housed in a thin aluminium alloy tube and fired by a pyrotechnic squib costing just a few pounds, assumed such an important role in protecting our aircraft? Simple. It is robust and effective, and was, for many years, the only means of providing aircraft protection against the infrared guided missile. The design philosophy of the flare was to produce an IR signature superior to that produced by the aircraft's engines, and thus seduce or decoy the missile away from the aircraft itself. That same philosophy essentially prevails today.

Aircraft of the UK, US and many other nations engaged in operations in all parts of the world, regardless of role or intent, are unfortunately vulnerable to both planned and indiscriminate attacks by regular, irregular or terrorist forces equipped with relatively cheap man-portable IR Surface-to-Air-Missiles. Though perhaps it is not as effective as the modern DIRCM systems being fitted to some transports and helicopters, the IRCM decoy flare is several orders of magnitude cheaper and has universal application. Driven by highly demanding performance specifications from the likes of our own dstl and its forebears, flare manufacturers have continually developed flare chemistry such that today's flares are capable of providing protection for any aircraft against virtually any MANPADS threat type that the aircraft may encounter.

British flares were first introduced to protect V bombers from the threat posed by Soviet Air-to-Air IR guided missiles. These flares had to be effective at heights of 40,000ft. During the Vietnam War era, the centre of gravity of the threat shifted to low level, where the likes of SA-7 Grail posed a major danger to US aircraft. That gave birth to the range of flare formats, which currently dominate inventories today viz: M206 (and its UK equivalent 118), and MJU-7 (UK 218). The IR source of these first generation flares was, and continues to be, a compound comprising Magnesium, Teflon and Viton (MTV). Magnesium is the fuel that produces the IR source (and bright light), Teflon is the oxidiser and Viton the binder to ensure integrity of the chemical pellet. Wallop, now known as Wallop Defence Systems Ltd, is still a major supplier of MTV flares to the UK MOD and other nations, particularly with its range of 55mm and HS4 flares for Tornado aircraft.

With the exacerbation of the SAM missile threat in recent years, mainly due to the advent of third generation dual-colour seekers on the missiles, flare manufacturers have produced a variety of different types of decoy concepts ranging from dual-spectral and pyrophoric compounds to ballistically modified and propelled flares. We chose to invest in developing a new chemical compound to produce an effective dual-spectral signature. After numerous national and NATO sponsored trials, the resulting HS1S pyrotechnic flare is undergoing formal qualification to enter UK Service as the 118S No1 Mk1 on rotary wing and some fixed wing aircraft. In conjunction with the UK MOD, we are also working on fast jet flares in both 218 and 55mm formats. The speed of the fast jet presents a different set of problems for our R&D chemists, as the 'light up' of the flare compared with the 'low and slow' 118S case is extremely challenging. The current Wallop 218S dual-spectral flare is in service as the interim solution and we have every confidence that the definitive fast jet flare will soon follow.