January 09, 2007

If a Boeing 767 runs out of fuel at 41,000 feet what do you have? Answer: A 132 ton glider. Who says commercial jetliners cannot glide? "The Gimli Glider" successfully pulled it off, and the failure of its nose wheel to deploy even saved lives. [last link = pdf]

During my recent holiday vacation, my mother gave me a ride on an ultralight plane as a gift. As I've never been too fond of flying, I was a little anxious over it. I got into a discussion with her boyfriend over plane safety, and he insisted that commercial jetliners would drop like a rock if they lost all engines. I seemed to think otherwise, and well, here you have it...

posted by sugarmilktea 17 years ago
  • Interesting story, but something about that first website doesn't seem right . . . Math Teachers: email me for a lesson plan based on the Gimli glider AA-HA! Math! I knew it!
  • Yet somehow this does not reassure me....
  • Weird... it appears I wrote my last comment in invisible text.... *test*
  • first math, then invisible comments = voodoo thread!! EVERYBODY PANIC
  • Funny, I had an argument with someone in a pub about 10 years ago on this topic, me taking the possible to make it down by gliding side. Vindication, though late, is sweet.
  • I am amazed that I had never -- it seems several of us have never -- heard this story before.
  • That was an amazing story - thanks for linking it.
  • old joke... Q: How's yer beer, need another? A: Like a 767 on final approach to Gimli.
  • The 'Atlantic Glider' incident was another. An Airbus A330 glided over the Atlantic for 115 miles to a landing in the Azores after losing all it's fuel. There are more here.
  • On a smaller scale, here's a video of an RAF hawk suffering engine failure on takeoff. Both crew ejected OK. No word on the bird that caused the crash: .wmv file
  • " 1.77 pounds/liter as the specific gravity factor. This was the factor written on the refueler's slip and used on all of the other planes in Air Canada's fleet. The factor the refuelers and the crew should have used on the brand new, all-metric 767 was .8 kg/liter of kerosene." How is 1.77 pounds different from .8 kg? Mathematically Challenged
  • How is 1.77 pounds different from .8 kg? Ah, the keyword being factor. 1.77 pounds is the same quantity as .8 kilograms, but this does not matter when you need to calculate conversions. Numbers aren't smart enough to realize that they may have units attached (i.e., 1.77 does not equal .8 if you take away the units). 1.77 is the multiplier that converts litres into pounds, not kilograms: to convert litres into kilograms you need to multiply by 0.8.
  • > How is 1.77 pounds different from .8 kg? The wikipedia entry is clearer on this. The problem arose at data input level, where the unit of measurement was confused. The dipstick measure indicated 11,525 litres of fuel, but converting this to weight they used 1.77 lb/L and got "20,400" (pounds). This was entered into the aircraft's computer, which interpreted it as kilograms because it had been switched to metric.
  • I first heard of this when I saw the movie (starring William Devane as the pilot). It is a pretty old story, no? I remember being shocked that they didn't know very much about the plane (admittedly it was new) and were hauling out three-ring binders to look for information -- the movie had it that they didn't even know about the ram air turbine for emergency electrical power and were delighted to discover that. Perhaps the movie was exaggerating somewhat ...
  • From the pdf linked above: The Gimli Glider incident received worldwide attention and became the subject of a best selling book and a TV movie. Pearson had a bit part in the movie, Falling from the Sky: Flight 174: you can see him holding a clipboard when the pilots come out of the simulator. However, he was unimpressed by the movie’s accuracy and was frustrated to see mistakes in aviation terminology. He preferred the book Freefall, by Marilyn and William Hoffer. Another intersting tidbit: But Pearson is relieved that he wasn’t flying an Airbus. “You can’t sideslip an Airbus aircraft, the computers won’t let you,” he says. “Boeing aircraft are capable because they’re a hydraulic controlled aircraft and you can cross control.” (the sideslip maneuver allowed the plane to make the runway)
  • The incident aircraft was the first aircraft in the Air Canada fleet that measured fuel in kilograms, whereas all of the other manuals and planes in the Air Canada fleet used pounds. This serves as a clear example of the perils associated the inefficient metric system, and the woeful misfortunes apt to be suffered by those renegade countries foolish enough to adopt such a system.
  • If only they'd stuck to their scruples. scruple = 0.33 drachm = 0.04125 fl. oz
  • AMAZING story.
  • On the Boeing/Airbus issue, as I understand it, the computers in an Airbus will not allow the aircraft to be pushed beyond certain limits (they are limits for a reason after all). The Boeing approach is (or was) for the computers to allow the maneuver, but to give the pilot feedback such as making the controls harder to move, and shaking the control stick. In normal flight they'll feel this and stop what they are doing, but if they really want to do it, for whatever reason, they will be able to. Seems like a good approach to me.
  • This was a fascinating read. I'd love to hear it from a passenger's viewpoint.
  • Brush with Greatness: I e-mailed the above links to a friend of mine who is a 767 pilot. He wrote back just now and sez: "Good article, thank you. I've flown the 'Gimli glider' many times. She's none the worse for her experience." How 'bout that.
  • This was a fascinating read. I'd love to hear it from a passenger's viewpoint. I keep thinking the same thing, Lara. How 'bout that. Fantastic-o, Ralph! Amazing that they were able to repair that bird so quickly, and that it's still in service.
  • MonkeyFilter: If only they'd stuck to their scruples. Yah, Lara & TUM. I keep thinking about the screaming till I'm absolutely hoarse. And the pucker marks--lordy, how did they put that plane in service with those pucker marks?
  • And now, the Galunggung Glider.
  • Thanks for the link, RTD. I kept asking myself, "yes, but why did all engines cut?" Aaaah, volcanic ash... Just goes to show, you can never deny the unexpected.
  • Heathrow Glider? The BBC said an unidentified Heathrow worker told the broadcaster that he had spoken to the pilot. The pilot said, according to the worker, that the plane's electronics had failed and that he was forced to glide it to the ground.
  • This is not the use of "Gimli" that I expected when I saw this on the sidebar. An awesome story nevertheless!
  • I just saw the MayDay dramatisation of this on TV. Of course, it's on YouTube (5 parts). Worth watching if you haven't seen it.