The unmanned bomber: the Ucav: for a few years now, an entirely new field of unmanned aircraft is being explored, with ups and downs. The main problem is to define the requirement, as nobody knows whether or not this category will be able to replace the traditional strike aircraft.

Following the termination of the US Air Force/Navy J-Ucas (Joint-Unmanned Combat Air Vehicle) programme in FY2007, the latter service has issued an RFP for a $1.9 billion, six-year technology demonstration programme (Ucas-D). Boeing is expected to offer the X-45N, which is derived from the X-45C demonstrator, while Northrop Grumman offers the X-47B. The production N-Ucas might nonetheless eventuate as a derivative of the Lockheed Martin F-35. The US Air Force is planning a much heavier manned/unmanned Long-Range Strike (LRS) aircraft on a much later timescale.

Europe's principal Ucas effort is still the Dassault-led, six-tonne Neuron, for which France's DGA signed a 405 million [euro] initial development contract in early 2006.

Others involved include Alenia Aeronautica, Eads-Casa, Hellenic Aerospace Industries, Ruag Aerospace, Saab and Thales. The Neuron is scheduled to fly in 2011.

If only because of their manned fighter purchases, none of the associated countries has an urgent need for a stealthy strike drone, hence it is difficult to envisage such an aircraft entering service before around 2030. Nonetheless, several European countries are funding national Ucas programmes, such as Britain's BAE Systems Taranis, Germany's Eads Barrakuda, Italy's Alenia Aeronautica Sky-X, Russia's Yakovlev Proryv (Breakthrough) and the lightweight Voron and Sweden's Saab Aerosystems Filur.