The Economist explains

What are MANPADS, the portable missiles bringing down Russian aircraft?

Britain is supplying Ukraine with its latest generation of STARStreak missiles

Mandatory Credit: Photo by London News Pictures/Shutterstock (1707995b)A gunner of 16 Regiment Royal Artillery mans a Starstreak High Velocity Missile System (HVM) at BlackheathMissiles on Blackheath for Olympics Security Test, London, Britain - 03 May 2012Two members of 16 Regiment Royal Artillery man a Starstreak High Velocity Missile System (HVM) at Blackheath in London today (03/05/12). The missiles have been deployed as part of an exercise involving the RAF, British Army and Royal Navy taking place across London as part of security preparations for the 2012 London Olympic Games

MAN-PORTABLE AIR DEFENCE SYSTEMS (MANPADS) are playing an unexpectedly important role in the war in Ukraine. These shoulder-fired missiles, typified by the American Stinger, are only effective against low-flying aircraft and at a range of a few kilometres. But they have scored a number of kills and are severely impeding Russian air operations. Now Ukrainian forces are getting an upgrade, in the form of the latest STARStreak missiles supplied by Britain. Why are MANPADS crucial to Ukraine’s defence, and what difference might the new missiles make?

Military analysts were puzzled when Russia failed to knock out the Ukrainian network of long-range, radar-guided S-300 surface-to-air missiles at the outset of the war. Though some have been destroyed, other S-300s continue to operate, forcing Russian aircraft to fly at low altitudes to avoid radar detection. And whereas NATO helicopters have mast-mounted sights that allow them to fire guided missiles from long range, Russian attack helicopters tend to carry pods of unguided rockets, behaving like slower ground-attack aircraft that must fly forward while attacking. Both of these factors put Russian aircraft in the sights of MANPADS.

Originating in the 1950s, MANPADS use infra-red seekers to home in on the hot exhaust pipes of jet engines. This is why aircraft and helicopters fire out fans of decoy flares, to distract such missiles with brighter and more attractive heat sources. Early MANPADS could only lock on to an aircraft from behind. These include the Soviet-era Strela (or SA-7, as NATO calls it) which Germany is supplying to Ukraine from old East German stocks. More modern missiles, such as the Igla (or SA-18) and the Stinger (which was developed in the 1980s), can be fired at an aircraft from any direction. However they may not be fast enough to catch a receding aircraft before it disappears out of range.

Modern heat-seeking missiles also have limitations. The Stinger missile seeker requires cooling, and a battery unit provides power for only 45 seconds, so it cannot be left continuously ready. The seeker head takes between three and five seconds to reach operating temperature after being turned on, an agonising delay when under attack. Once the Stinger is live, the weapon must identify the aircraft’s engine heat and lock on. And once fired, the missile may be thwarted by decoy flares or other countermeasures, or the pilot may manage to break the lock-on by pulling a sharp turn. A Stinger flies at about twice the speed of sound and carries a one-kilo explosive warhead fused to explode on impact. That is not necessarily enough to destroy an aircraft but almost certainly enough to force it back to base.

The battlefield effectiveness of the Stinger is highly contested. Its main use in action was by mujahideen in Afghanistan in their fight against the Soviet Union. Their reports of a 79% success rate may have been intended to convince their American backers to keep supplying the weapons. The reality may have been more like 20%.

The STARStreak is somewhat different. Ukraine received its first one in mid-March. Whereas the Stinger is battle-proven, this will be STARStreak’s debut in combat. The weapon was developed in the 1980s, though the latest version, STARStreak II, was first demonstrated in 2008. STARStreak is unusual in not being a heat-seeker but a “beam-rider”: the operator holds the target in the cross-hairs and the missile follows, guided by a laser beam. A disadvantage is that the operator has to follow the target. But that makes it in effect immune to decoys, countermeasures and evasion. If you can see it, you can hit it.

STARStreak’s makers call it a “high-velocity missile” to draw attention to its speed of more than Mach 3, which makes it much harder to evade. And rather than Stinger’s single warhead, STARStreak releases three tungsten darts, each weighing 900 grams. These spread out and fly in formation, all following the laser guidance, increasing the chance of a hit. The darts can pierce helicopter armour and explode after penetration, causing far more damage than a surface explosion.

It may be that this ultra-modern weapon proves too complex or fails to match expectations. However, reports from Ukraine suggest that a STARStreak has already brought down a Russian Mi-28 helicopter. Ukraine’s government has repeatedly asked NATO to impose a no-fly zone. It will almost certainly not get one. But STARStreak missiles, and MANPADS more generally, could help Ukrainian forces to neutralise Russian airpower without the need for new jets or direct intervention by other states.

Read more of our recent coverage of the Ukraine crisis

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