Stealth is becoming affordable, according to EADS. Jan Ritter, head of the computational electromagnetics (CEM) group in EADS Military Aircraft division, says that the mindbogglingly complex task of calculating how radar waves scatter off a complex shape - at all relevant angles and frequencies - is succumbing to advances in computing and better codes. CEM is now becoming mature, Ritter said Tuesday at IQPC's conference on Military Aircraft Survivability in London, just as computational fluid dynamics (CFD) has improved aerodynamic design.
EADS has developed modification packages for aircraft such as the Tornado, reducing radar cross section (RCS) by 10 dB, says Ritter. "More complex means" - including the replacement of some structural parts - can cut the RCS of a conventional-looking aircraft by 15 - 17 dB, which substantially reduces detection range and (to an even greater extent) boosts the performance of electronic jamming, because a hostile radar needs more power to see the weaker target through the jamming signal. EADS has even developed a package of RCS-reduction measures for the A400M transport, not to make it invisible but to make its towed radar decoy more effective. Interestingly, EADS estimates that the Super Hornet has an RCS 20 dB lower than the original F/A-18C/D, getting close to the values for aircraft like the F-22 and JSF.
For all-out stealth aircraft like the Barracuda UAV, EADS has developed codes that can deal with up to 6 million unknowns, performing "accurate, full-wave solutions" of Maxwell's equations - the root of all radar stealth work - and can work fast enough to be part of a multi-disciplinary optimization (MDO) design process. The result is designs that can balance stealth, performance and cost.