Israel's state airline, El Al, has confirmed that it will begin installing missile defense systems on some of its passenger jets. The decision to install self-protection systems was actually made in 2002, after Al-Qaida terrorists tried (unsuccessfully) to down an Israeli charter jet over Kenya, using a shoulder-fired, SA-7 surface-to-air missile (SAM).
According to the Israeli daily Harretz, El Al will mount "Flight Guard" defensive suites on six of its jetliners that routinely fly to areas where Al-Qaida has been active in the past. The airline does not have current plans to install the system on the rest of its aircraft, but that might be an option as the threat from man-portable missiles increases.
The Flight Guard systems consists of a missile warning system, linked to flare dispensers mounted at various locations on the aircraft. When warning sensors detect a missile launch, the system begins dispensing hot flares, designed to decoy the missile away from the aircraft.
Systems like Flight Guard are effective against older shoulder-fired, like the Russian-built SA-7/14 series, and the U.S. manufactured Redeye, which are readily available on the black and gray arms markets. But the systems are not foolproof. To detect a missile, the system scans the environment for a spike in infrared (IR) energy, typically associated with a missile launch. Unfortunately, other events--such as sunlight reflecting off a lake, or a "hot" cloud can produce similar spikes, resulting in false alarms and flare deployments.
Compounding the problem, those decoy flares burn very hot and they do fall to earth. While they're supposed to burn out before reaching the ground, residual heat can still ignite dry material--such as brush or foilage around an airport, or beneath a departure/arrival corridor. Can you imagine what might happen if an airliner dispensed flares around the Dallas-Ft Worth Airport, or Will Rogers Airport in Oklahoma City? Firefighters might be busy for days, given the dry conditions and on-going wildfire threat.
Of greater concern is the reduced effectiveness these systems have against newer man-portable SAMS, including the Russian SA-18/24 and the latest version of the U.S.-built Stinger. More advanced MANPADs have built-in flare rejection capabilities, allowing them to "recognize" flares and regain lock on their target. Al-Qaida (and other terrorist groups) may have access to these weapons, reducing the protection offered by Flight Guard.
From the Israeli perspective, even limited protection is better than nothing. There are also indications that Flight Guard is an interim measure and will eventually be replaced by a system called BRITENING, which links missile detection sensors with an advanced IR jammer, designed to blind the seeker of a shoulder-fired SAM.
U.S. manufacturers produced similar hardware, notably the NEMESIS system built by Northrop-Grumman. The FAA (and other government agencies) have been evaluating NEMESIS (and other self-protection suites), but so far, there has been no decision to actually mount anti-missile defenses on U.S. aircraft. At a cost of $1 million per jetliner, it's an expensive proposition, one that the government and financially-strapped airlines seem unwilling to undertake.
On the other hand, what would be the likely cost--in decreased travel, lost jobs and permanently-grounded airlines--if a terrorist managed to shoot down a jetliner inside the CONUS. Suddenly, the cost of putting missile defensive systems on airliners might seem like a relative bargain.