It appears that plans for patrolling robotic laser missile-muddler guardian aircraft above US airports have been shelved. The idea has been assessed as too expensive to be practical.
Under the US Department of Homeland Security (DHS) "Project Chloe", the unmanned aeroplanes would have been equipped to detect any possible terrorist surface-to-air missile launches against airliners departing or arriving from the airport below. The droid protectors would then have used powerful laser dazzlers to confuse the missiles' seeker heads, sending them safely off track.
Flight International reports today that US weaponry'n'aerospace globocorp Northrop Grumman, hired by the DHS to evalute the Project Chloe plan, has found that it would be much more difficult and expensive to implement than the security bureau had thought.
The evaluations have included simulations, and test flights using the White Knight high-altitude jet operated by Scaled Composites, which famously carried the X-Prize winning SpaceShipOne to glory and is now used as a flying testbed.
The possible area of ground from which a Man Portable Air Defence System (MANPADS, a shoulder-fired missile) could hit a low-flying airliner is large. MANPADS can strike within a plan range of 5km or so, and at heights up to ten thousand feet. This means that three Project Chloe patrollers at 65,000 feet would be needed to cover each airport, not one as the DHS had thought.
"You're looking at a fleet of great numbers. It becomes a very costly approach," Northrop's Dave Denton told Flight.
MANPADS have already been used by terrorists and insurgents. An Israeli charter flight was targeted using MANPADS in Kenya in 2002, and a British military helicopter was shot down over Basra in 2006 using a Russian SA-14 probably supplied via Iran. Going further back, the CIA supplied large numbers of effective "Stinger" MANPADS to hardline Islamic mujahideen in Afghanistan during the 1980s, for use against Russian aircraft.
That said, however, MANPADS are hard to get hold of - much rarer than simple RPG unguided armour-piercing rockets - and require more skill to maintain and use. Given that even RPGs have seldom been seen in the hands of domestic terror cells in Western nations, there are those who doubt that MANPADS are a likely threat to normal airliner operations. Even in Middle Eastern warzones, though the fear of MANPADS often heavily circumscribes the operations of western air forces, such weapons appear only rarely.
In any case, it appears that the Project Chloe airliner-protection scheme is dead in the water. Northrop are due to report on Chloe in January, and after that little further progress is foreseen.
"DHS has not suggested there's any continuation of the programme for Chloe and anti-MANPADS," Denton told Flight. "They have not suggested to us there is any more funding."
However, the DHS has other MANPADS-buster schemes - for instance robotic suicide bodyguard escort planes, or the fitting of airliners with military-style dazzler countermeasures. These too have their critics, but remain under consideration for now. ®