Efforts to equip US airliners with laser defences against missile attacks are gathering pace, but cheaper solutions have not been ruled out
With flight testing of military-style laser jammers on airliners to begin this week, debate continues over their suitability for commercial operations as well as the desirability and practicality of equipping civil aircraft to defeat terrorist missile attacks. The tests of directed infrared countermeasures (DIRCM) systems developed by BAE Systems and Northrop Grumman are the culmination of the 18-month second phase of the US Department of Homeland Security’s (DHS) programme to counter the threat posed by man-portable air-defence systems (Manpads).
While the airlines criticise the DHS for focusing its resources on the development of expensive DIRCM systems, legislation has been introduced in Congress that would require fleet-wide installation. And while the airlines lobby for a layered approach to meeting the missile threat, Congress is considering a bill that would require the Airbus A380 and Boeing 787 to be equipped with laser jammers within two years of certification.
Congress is also poised to approve funding for Phase 3 of the DHS’s Counter-Manpads programme, which in addition to installing DIRCM systems on multiple aircraft for in-service evaluation would provide money to study alternative ways of protecting airliners. This has given hope to those who would prefer a cheaper approach, such as flare-based self-protection systems for aircraft or ground-based high-energy laser or high-power microwave weapons at airports.
Those opposed to installing laser jammers on airliners have seized on a report released by Rand in February, in which the research organisation estimated the cost of equipping the 6,800-aircraft US commercial fleet at $11.2 million, and projected operating and support costs of $2.1 billion a year once all the systems are installed. While it has not been decided whether the government would pay for installation or operation, Rand notes that $2.1 billion a year is almost half of the DHS budget for all transport security.
The DIRCM manufacturers point out that Rand’s estimates are extrapolated from the procurement costs and reliability figures for military systems, and do not take into account the cost reduction and reliability improvement goals set for the commercial systems by the DHS. Rand’s maintenance cost estimates assume a mean time between failures (MTBF) of 800h, based on projected military system reliability. Increasing the MTBF to the DHS target of 3,000h for the commercial system reduces the estimated annual operating and support cost to $0.9 billion, the report says.
Cost questions
“Fundamentally we agree with the Rand report,” says Steve Dumont, BAE’s Counter-Manpads business development manager. “At the time they collected the data, two years ago, the technology did not have inherent reliability, and was too expensive for commercial use.” Both firms argue the DHS programme is changing the equation by driving down cost and increasing reliability. “The DHS set up this programme not just to put military systems on commercial airliners. It is designed around the commercial reliability requirements for avionics,” says Jack Pledger, Northrop’s IRCM business development director. “If you substitute the DHS data, the Rand report makes more sense.”
Rand extrapolated an average unit cost of $1.3 million, while the DHS has set a target of no more than $1 million by the 1,000th system. “The system costs much less than that, installed and ready to fly away, including training, technical data, aircraft modifications and the pod,” says Pledger. “The cost is equivalent to an in-flight entertainment or internet system.” The projected operating cost is 0.1¢ per seat mile. “On a 767-sized aircraft flying coast to coast, that’s $3 per passenger.”
While Northrop has stuck to its “one size fits all” universal pod design, BAE has moved away from its original approach of mounting all of the system in a bolt-on canoe fairing. “Fuel cost is a critical factor, as there is a significant impact on the aircraft from a drag perspective,” says Dumont.”We now have more of the system distributed through the aircraft, to provide a more benign environment and to minimise the drag.”
Northrop has packaged the four missile warning sensors, laser jam head and electronics in a canoe that can be attached to any aircraft, from 737 to 747 size. BAE locates the system electronics in the cargo hold and electrical equipment bay and leaves only the sensors and jam head exposed. “We continue to look at the packaging to reduce drag and weight,” the company says.
More aircraft are expected to be modified with the “A-kit” provisions than there are sets of “B-kit” missile-defeating systems, requiring equipment to be rotated between aircraft. “We still intend to have remove and replace times within standard airliner maintenance times,” says Dumont. “More important is the ease of maintenance replaceability. Low-cost carriers have a 20-30min turn time and we need to fit within that window.” The system boxes are located where they can be removed and replaced during standard maintenance, he says.
“We are sticking with the pod,” says Pledger, to minimise the time an aircraft is out of service for modification, which will be performed during heavy maintenance. Based on the more than 27 types modified with Northrop’s military DIRCM, “to do an installation integral to the aircraft takes that aircraft out of service for three to five weeks”, he says. “We can modify an aircraft to accept the pod in four days or less, and not add any time to a C check. Then it takes less than an hour to put the pod on or take it off. Aircraft can be traded, moved in and out of service, and in and out of areas that need DIRCM.”
Weighing around 225kg (500lb) – the equivalent of two passengers and their bags – the 2.1m (7ft)-long pod would be fitted using a scissors truck, a process similar to installing an emergency slide, says Pledger. Scheduled maintenance of the DIRCM is designed to coincide with airline maintenance cycles. “Filters and dessicants, which need to be replaced after several months, are all that are required to maintain the system,” he says.
Ready to fly
Northrop planned to begin flight testing its countermeasures system on 29 August, using a FedEx Express Boeing MD-11 modified to mount the DIRCM pod under the rear fuselage. Initial flights will be without all of the equipment installed in the pod, which is instead instrumented to gather aerodynamic data for certification. “The aircraft was flown first without the pod, so that we can measure what it is doing to the aircraft,” says Pledger. “The first pod to fly is instrumented for aero data, to get the aircraft cleared to fly with the real pod.”
Flights with a functional DIRCM pod installed are to begin early in October, and will include tests of the system’s ability to detect, track and jam shoulder-launched missiles. These will use a missile simulator on the ground at Mojave airport in California. “We will fly the aircraft over at different aspects and altitudes, activate the missile warner with the surrogate threat, and measure the output to determine whether the system is putting out a signal with adequate strength to defeat the missile,” Pledger says. A Northwest Airlines Boeing 747-200 equipped with an identical pod will fly later in the year, and flight testing is intended to lead to FAA supplemental type certification (STC) of the Northrop system on both aircraft types.
First shipment
BAE, meanwhile, planned to ship its first system to American Airlines late in August for installation on a Boeing 767-200 that has been taken out of revenue service and modified with provisions for the DIRCM. Ground tests will begin in the latter part of August and flight tests in early September,” says Dumont. The first phase of flying will cover the airworthiness testing required for supplemental type certification of BAE’s DIRCM on the 767. During the second phase, the aircraft will be flown against a threat simulator on the test range at Eglin AFB in Florida to evaluate the system’s ability to defeat missiles.
Flight testing is to be completed by the end of the year, with both teams to file their reports early in January so that the DHS can present the results of the Phase 2 programme to Congress in February. “It’s a very aggressive schedule,” says Dumont. The results of Phase 2 are expected to determine whether the US government will mandate DIRCM installation on at least some commercial aircraft, but the DHS is already planning to field more systems.
The proposed Phase 3 programme involves the installation of pre-production systems from both manufacturers on multiple aircraft types for evaluation of their reliability and maintainability in revenue service with several US cargo carriers. Plans call for 20 aircraft to be modified and 16 systems to be procured for operational testing, which would last a year and provide data to improve the life-cycle cost analysis. This will require additional STCs.
Phase 3, for which $110 million in funding is being sought for fiscal year 2006, will also include live-fire testing of the systems to determine their effectiveness when installed on a commercial aircraft; and “an aggressive reliability growth effort” to achieve the 3,000h MTBF target. “Phase 3 will verify whether we are meeting the commercial airline reliability requirement,” says Pledger.
Controller alert
Under Phase 3, the systems will be upgraded to incorporate new requirements such as protection of the laser jammer technology and emergency ground notification, so that controllers are alerted when the DIRCM has been activated and security forces are directed towards the source of the missile attack. Also under Phase 3, the DHS plans to begin working with Airbus and Boeing on building provisions for DIRCM into future production aircraft.
About $10 million of the Phase 3 funding will be allocated to studying alternatives. Raytheon plans to propose its Vigilant Eagle high-power microwave weapon, which sends an electrical pulse into the missile to damage its guidance electronics. Two billboard-sized phased arrays mounted back to back and looking either direction along the runway would create and steer 1°-wide beams to provide a protective dome over the airport.
While it did not consider high-power microwave weapons, Rand concluded that high-energy lasers promise to be effective against all types of missile, but will not be available for several years. The report also said several systems would be required to protect an airport. Raytheon estimates its system can be built for $25 million per airport, with protection of the top 31 US airports – which handle 70% of take-offs and landings – costing less than $1 billion.
L-3 Avisys, meanwhile, is hoping for a second chance to offer a flare-based solution, originally rejected by the DHS because of safety concerns. The company’s WIPPS system, which combines pulse-Doppler and ultra-violet missile warning sensors to eliminate false alarms, has been on service on a Jordanian VIP Airbus A340 for 18 months with no false alarms or flare dispenses in 130 flights, says Jim Carrey, vice-president of business development.
Although Israel is on the verge of certificating an expendable-based system (see box), the FAA remains concerned about pyrotechnic flares causing ground fires and false alarms causing panic. Frustratedly, Carrey points out that US fighters routinely dispense flares over Washington DC when intercepting aircraft that stray over the US capital.
While Carrey accepts that a DIRCM is a “acceptable solution” for widebodies, he argues such systems are too large for the 5,000 US narrowbodies and regional jets, or for business jets. “We have to do something to get rid of the drag,” he says. While flare-based systems are lighter, cheaper and lower drag, the Rand report concluded they were less effective than laser jammers against later-generation missiles. Advances in visually covert, fast-burning pyrophoric flares may address the safety and effectiveness concerns, but certification remains a hurdle to be overcome. -
GRAHAM WARWICK/WASHINGTON DC
Source: Flight International
