You’ve got your computer problems and I’ve got mine, but the flight crews of Boeing 787 airliners apparently have us all beat.
The Federal Aviation Administration (FAA) is issuing a rule requiring urgent attention by operators of Boeing’s 787 Dreamliner to avoid the possibility all three computer modules that manage the jet’s flight-control surfaces could briefly stop working while in flight.
Operators must periodically shut and restart the electrical power on the planes, or the power to the three flight control modules. That will avoid the problem until Boeing has a permanent software fix.
In an airworthiness directive to be published Friday, the FAA said it is reacting to indications that “all three flight control modules on the 787 might simultaneously reset if continuously powered on for 22 days.”
It said such a simultaneous reset in flight “could result in flight control surfaces not moving in response to flight crew inputs for a short time and consequent temporary loss of controllability.”
“Uh, yup. There’s your problem right there,” said no mechanic ever as the vehicle he was working on corkscrewed in from 35,000 feet. But it did leave me wondering: Do people really leave the power on in those things for over three weeks at a time?
Once when I was a dealership mechanic I had the opportunity to get into aircraft maintenance instead. Thought it over hard through a weekend, then decided nope. I was too much of a worrier as it was.
I have always maintained that having identical computers running the same software does not constitute redundancy. Why? Because there is nothing to stop all of them dying (or going blue screen) at exactly the same moment, caused by exactly the same software glitch.
This seems to be an instance of exactly that!
I’m reminded of this fiasco:
But no worries. The Navy is still paying for WinXP support for the foreseeable future.
How long does the reboot take? I can see a piece of masking tape stuck to the instrument cluster “don’t forget to reboot B4 flight”. A real confidence builder.
And what Ben said.
The more of these stories I read, the more I think manufacturers should be trying to minimize computerization in the equipment they sell. My A/C stopped working a few weeks ago (fixed now) due to a screwed up computer component. I KNOW that air conditioners existed, and worked, before the introduction of computers, and I don’t believe that whatever advantages computerization confers are sufficient to compensate for the hassles is imposes when some stupid circuit get fried.
Making national defense dependent on these finicky pieces of hackable trash strikes me as insane.
Yeah, real redundancy is a little more complex than they’re making it out to be. But let’s face it, there’s only so much you can do with aircraft. Once they settled on “fly by wire” for airliners, it would add enormously to the cost, complexity and weight of the aircraft to install truly redundant hydraulic or pneumatic control systems. And doing so might make the plane safer in the one-in-a-million “Oh god we’re all gonna die” failure but the incidents of planes turning back because of a perceived fault in an essential-in-an-emergency redundant system would increase explosively. True redundancy probably isn’t practical.
In military transport aircraft I don’t understand why they couldn’t build non-computerized control systems. They certainly used to. But fighter aircraft are so complex and inherently unstable that only computers could ever keep them flying.
I’m a bit of a motorcycle fanatic, & I continuously bemoan the switch to “ride-by-wire” on newer bikes. 4 of my 5 bikes were built before 1983; anything goes wrong with them, I can either find a part, or I can modify an aftermarket part or a part from another bike, sometimes one from another manufacturer. One can pick up old UJMs for little money & get ’em going. What happens in 15 years when Craigslist is full of ads saying “bike mechanically sound, electronics fried” & nobody makes the box o’ imps for it anymore? There’ll be a bunch of two-wheeled boat anchors out there.
“UJMs”?
“box o’ imps”
I am so stealing that.
The imps die because they all smoke; we all know electronics quit when the magic smoke is released.
“truly redundant hydraulic”
We had an old-school A-6 Intruder military aircraft land (barely- I was there) with man-sized holes in both wings due to overpressured tires exploding in flight. The hydraulics were impressively armored but torn asunder and still leaking when I looked at ’em. Who needs redundancy when you build it macho-tough in the first place? OTOH, that way is also horrendously expensive.
UJM = “Universal Japanese Motorcycle”
😉
Good thing you didn’t get into aircraft maintenance. Every time a guy works on a plane he signs off on the maintenance he’s done in a log. Once the investigators have found out why an aircraft has “fall down and go boom” the next step is to check the logs and see who was the last one to work on whatever failed. Then they take out the rope, find a tall tree and the maintenance guy who did the work gets to play Danny Deever.
Robert: That’s what they taught me in Navy avionics school; let the smoke out, the trons don’t work anymore.
I used to call a computer a “demon box”; once I started reading Terry Pratchett, I decided they’re stuffed with imps. I actually understand how computers work (USN again), but it’s more fun to think they’re boxes full of industrious imps (possibly unionized, constantly surly).
Tenn Budd:
Slightly OT, we had a big honkin’ sledge hammer on a bulkhead hanger in case we needed to smash things prior to abandoning ship. It was painted a purty black and silver with the legend “Maxwell’s Silver Hammer”. More than once, when the imps were particularly surly, we were tempted to prematurely dismantle the computers.