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Fly-by-Wireless Plane Takes to the Sky
galactic_grub writes to tell us that engineers in Portugal have built and flown a plane with no wires or mechanical connections between the major systems, only a wireless network. From the article: "Tests flights carried out in Portugal have shown that the system works well. Cristina Santos, at Minho University in Portugal, who developed the plane, says the aim is primarily to reduce weight and power requirements. 'Also, if you do not have the cables then the system is much more flexible to changes,' she says."
Pretty darn resistant to lightning, actually. A lot of designing goes into making sure that critical systems remain functional and that nothing carries an excessive current in the event of a lightning strike, which happens a lot more frequently than most passengers probably realize. During the 80's NASA did a very extensive investigation into the effects of lightning on airplanes. Some of the test pilots involved had their planes hit hundreds of times while deliberately flying through the most active parts of the storms. A source I just googled up says the average passenger plane gets hit once a year. According to another source the last commercial airline accident attributed to lightning was in 1967, which was due to a fuel tank explosion, not a control outage.
Old style plane controls were based on either cables (not suitable for larger aircraft) run from the pilot's controls (yoke, pedals, throttle) to the control surface or else on hydraulics. In the latter, there are hydraulic valves actuated by the pilot, and the pressure is transferred via hose from the pump to the valves to hydraulic cylinders or motors that move the control surfaces. Anyone who is familiar with hydraulics knows how heavy those components are. Fly-by-wire eliminates the direct link, allowing much shorter hydraulic routing, replacing hoses with pumps at the point of use, or even replacing hydraulics with electrical actuators. All the components are surge protected and wiring is typically triple redundant.
I believe there are three dangers presented to airplanes by lightning: interference, stray currents, and energy dissipation. Interference can be dealt with by minimizing the opportunity to pick up signals (the 777 for example uses fiber optics instead of wires) and signal processing. Stray currents, which can damage componenets, are handled by isolating the electrical systems from the structure and using surge protectors. By energy dissipation I mean resistive heating of the airframe. This normally isn't a problem with aluminum airframes/skins, because the bolt passes straight through the plane with little trouble. With composite fuselages like on the A380, there is typically a safe path designed into the system for the same purpose. Otherwise a bolt might find a relatively small current path and overwhelm it, heating it so fast it could actually vaporize violently (a somewhat more technical way of saying it explodes).