Nanotechnology is set to drive a revolution in "intelligent avionics" that will help cut aircraft fuel burn and improve safety.

A technology forecast by PricewaterhouseCoopers envisages wireless sensors becoming so small that aerospace engineers of the 2020s will be able to embed layers of them in or on components or structures.

So-called "smart dust" promises to revolutionise avionics, by communicating wirelessly from any part of an aircraft to back up avionics systems. PwC emerging technologies director Dr David Jacobson said: "The layered back-up will reduce the chances of sensor or software failures leading to a shutdown of flight-critical function, without adding weight."

He said that means aircraft could fly with greater safety using less fuel.

The concept, he says, is an extension of the current trend in avionics design to adaptive control, with increasingly compact sensors more widely distributed to improve the performance of fly-by-wire control systems, which intelligently adjust aircraft control surfaces to a pilot's intended course.

Jacobson said that reaching the smart dust stage depends on electronic component progress continuing to follow "Moore's Law", the axiom that says the number of transistors that can be placed on an integrated circuit doubles roughly every two years - an exponential rate of improvement that has held for more than 40 years.

He conceded that many experts believe Moore's Law will reach its limit by 2020 when it comes to silicon-based electronics. But he believes that advances in miniaturisation will continue thanks to nanotechnology, which is likely to turn up new materials and improvements such as the printable semiconductive polymers known as "smart plastics".

In addition to making it feasible to embed sensors in many components and surfaces, nanotechnology - the manipulation of materials at the molecular or atomic level, which takes its name from the nanometre, or one-billionth of a metre, scale - promises the development of new materials with novel properties.

Jacobson also expects a revolution in the stealth performance of military aircraft owing to a combination of nanotechnologies and new surface treatments using specialised laser techniques. He said these will give rise to materials and surfaces whose strength and electromagnetic wave absorption and radiation properties can be dynamically altered. "These will likely lead to the emergence of adaptable 'radar cloaking' of low-profile stealth fighters and bombers," he added.

"Nanotechnologies and surface treatments might well create new surfaces which, like a chameleon, change their patterns and reflective properties according to the background and incoming radar probing signals."

Applications for civil aircraft and spacecraft should also follow from materials and surface treatment techniques developed for military use, Jacobson has predicted.

Even without shrinking sensors to the point where they can be embedded in other materials, wireless technology is seen as a key emerging technology. As PwC observes, wireless systems offer the prospect of monitoring parts of an aircraft that are inaccessible to the current generation of wired systems. A significant enabler will be a common, dedicated radio spectrum for commercial aircraft.

Many of the benefits of added monitoring could best be achieved through modular avionics systems, in which a single black box would control a variety of systems. One great advantage over current-generation products would be ease of upgrades.

A related development is the push to replace hydraulic actuation of mechanical systems with electric control. Such more-electric concepts will be best realised with a better-integrated aircraft electrical system, to provide the right amount of power to any given part of the aircraft at any moment.

Source: Flight International