Air Transport

Bids are due this month for a US Department of Homeland Security experiment in using high-altitude long-endurance unmanned air vehicles to protect aircraft against missile attacks during take-off and landing at major US airports.

Contract awards are expected in August, leading to a demonstration in fiscal year 2008. As an intermediate step, the DHS is to carry out a sensor risk-reduction trial aboard either a General Atomics MQ-9 Predator B or Northrop Grumman RQ-4 Global Hawk by October.

The $12.7 million demonstration follows a US Congressional directive to explore multiple approaches to protecting airliners from man-portable missile attacks in parallel with work on fitting airliners with directed infrared counter­measures systems.

According to an announcement on 27 March, the project is intended to demonstrate "an alternative concept of providing persistent stand-off airborne Manpads protection for all commercial aircraft within a designated geographic area" by coupling high-altitude endurance UAVs with counter-Manpads technology.

The first likely approach would see all missile warning sensors and countermeasures equipment mounted on one or more HALE UAVs orbiting above an airport at 60,000ft (18,300m) to provide continuous surveillance and protection. The second would see a HALE UAV co-operating with a network of sensors and countermeasures on the ground or other aircraft.

The core requirement is to protect aircraft flying within airspace bounded by the threat envelope - a 4.8km (3 mile) radius around each aircraft operating at or below 18,000ft - along standard approach and take-off corridors that nominally extend up to 105km from the airports.

Airports to be studied are Denver, Las Vegas, Los Angeles, New York Newark, San Diego and Washington National.

Initial responses close on 25 April with full proposals due on 8 June.

External links: General Atomics, Northrop Grumman