It's every passenger's worst nightmare: You're cruising along at 30,000 feet when the lights suddenly go out and the engines quit. The cockpit crew has been struck down by food poisoning. A terrified stewardess (sorry, "flight attendant") yells out: "Is there a pilot on board?" OK, that's a bad movie plot. But what happened in London on Thursday is actually scarier, and would've been a huge disaster, if not for the hero pilot.What happened was, a British Airways plane on final approach into London's Heathrow Airport lost both engines and all power to the on-board electronics systems. Apparently everything went south except an altimeter and air-speed indicator running on battery backup.

Yet the pilot, Capt. Peter Burkill, was able to glide the plane in for a landing. (Go here to see a photo of the battered plane.)

Yes, the landing gear collapsed and 13 passengers suffered minor injuries. But it could have been far, far worse. The landing is being hailed as a miracle, because the pilot was able to react in basically no time at all and bring the heavy aircraft down.)

My point in blogging about this is to raise a couple of points I haven't seen in any of the news coverage.

First off, I take issue with the characterization of the safe landing as a "miracle." That's a cheap and lazy description. It wasn't a miracle; it was the result of a well-trained pilot doing what a consummate professional does. Anyway, my purpose isn't so much to denigrate the people tossing about "miracle." It's rather to point out that most folks don't really know what pilots are sometimes called on to do.

There's an added level of nuance on top of that. Namely, even when the cockpit crew performs spectacularly, things don't always work out. There's the case of the July, 2000, crash of a Concorde, shortly after takeoff in Paris. The pilot there was a hero, too, because he was able to divert the plane away from a populated area before it went down in flames, killing all 113 aboard.

Fly-By-Wire Hazards

My second -- and more important -- point, though, is to raise the issue of how modern planes like the Boeing 777, by their very design, are more of a problem in crisis situations than older planes.

That's because the 777 is a so-called "fly-by-wire" aircraft. This means it essentially uses computers to control the flight surfaces (wings, rudder, etc.). Commands from the flight deck are transmitted to the physical plane through wires and computers and finally to the hydraulic actuators which operate the control surfaces. This is in contrast with older, nonelectronic designs, where you had cables directly connected to the control surfaces. (More correctly, on large aircraft, these controls were boosted by hydraulic actuators, which pretty much means they used transmission fluid running through piping, analogous to your car's brake lines.)

Quite frankly, I wasn't aware that the 777 had a back-up mode where pilots could (directly?) operate the control surfaces in the event of a total power loss. (I couldn't find an answer to this question in my quick research this morning.) So, either the 777 does indeed have manual backup, or it didn't completely lose all power. Possibly all the control surfaces are hooked to some kind of UPS (uninterruptible power supply), which keeps them running on battery back-up in the event of an outage. (In that case, it's lucky the power loss happened during landing. If it occurred mid-flight, there'd be a question of how much time the pilot had on the backup supply before everything conked out.)

Anyway, my main point is that many people have been concerned for a long time about the inherent weaknesses in fly-by-wire. (The benefits are a lighter, more sophisticated plane that's cheaper to operate.) These are many of the same folks who were worried when twin-engine planes were certified for over-water operation. (In the old days, you had to have four engines to fly across the Atlantic, to provide a margin of safety.)

Consider British Airways Flight 38 to be both a close call and a warning. Just because fly-by-wire hasn't bitten anyone in the butt so far doesn't mean it won't one day.

Here's a video of the British Airways plane on the runway at Heathrow:

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