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I expect that most folks would be surprised to hear that Captain Bob Pearson was demoted for six months [0] after this landing, in which he side-slipped a comme

I expect that most folks would be surprised to hear that Captain Bob Pearson was demoted for six months [0] after this landing, in which he side-slipped a commercial airliner with no functioning engines, and dodged two kids on bicycles on the Gimli 'runway' (read drag strip). Talk about a uniquely Canadian story - running out of fuel because of a mistake in Imperial to Metric unit conversion. This from someone who was in high school in 1978, The Year Dope Dealers Got an 'A' in Math. And if you don't get that joke, you're not a Canadian who grew up in the transition from Imperial to Metric. [0] https://en.m.wikipedia.org/wiki/Gimli_Glider https://en.m.wikipedia.org/wiki/Gimli_Glider [edit: duh, added the reference. I get it, after having it being explained to me. Thanks folks. ]

boterock 10y ago
why do you do [0] and never put any [0]() =(
- vic-traill 10y ago
  CS man! What can I say? :-)
  - ythn 10y ago
    No, he means, where's the reference? I would be like if I said: Scientists recently proved the existence of a soul inside of all life forms [0].
    - vic-traill 10y ago
      Well played, sir!
  - nkozyra 10y ago
    Every CS paper I've had to write required valid references [1]
- qwertyuiop924 10y ago
  Indeed. Unterminated references are a sure sign of sloppy thinking[0]. They can also be dangerous[1]: gaze into the void, and the void gazes back. Cast into void, and you might get a null pointer exception.
sova 10y ago
Wait, Canada converted from Imperial to Metric? Wow that's amazing! I wish the US would do the same.
- deleted 10y ago
  [deleted]
- auxym 10y ago
  Only 3 countries in the entire world have not adopted SI units.
  - techdragon 10y ago
    Actually Liberia and Myanmar have been converting to Metric, so the USA is likely the last place where people are not being taught Metric. Unless it's improved and Metric is being taught in American schools?
    - learc83 10y ago
      Metric has been taught in most American schools since the 70s. Nearly everyone here learned it at some point, but most people don't use it day to day, so they don't think in it.
      - Shivetya 10y ago
        yeah but its not like its pushed much outside of chemistry. my niece and nephew have learned less about it than I did over thirty years ago. it simply is not a priority, it could be slowly slipped into prominence by emphasizing the measurements on everyday items instead of making those in small print
        learc83 10y ago
        >yeah but its not like its pushed much outside of chemistry Every science class I had in high school used metric. We also spent a fair amount of time going through it in elementary and middle school math classes. My younger sister (by 20 years) spent a good deal of time on the metric system in her math classes.
caconym_ 10y ago
IIRC they put a few other aircrews into the same scenario in simulators, and they all crashed. I think what the crew accomplished here is one of the most impressive and inspiring human feats I've ever heard of; more people should be familiar with the story. Like, sure, Pearson had glider experience... but he applied that experience flawlessly in an aircraft with a brick-like glide ratio, landing with no slats or flaps, all the while losing control authority as the airspeed dropped and made the RAT less and less effective, with 69 human lives at stake. Holy shit. For anyone who's interested, Wikipedia is full of these stories of disasters and near-disasters, and they make for interesting reading.
- jsight 10y ago
  A glide ration of 12:1 is not great, but isn't exactly brick-like either. A Cessna 172 has a glide ratio of about 9:1. Pilots spend a lot of time practicing gliding in airplanes like that (Cessnas, Pipers, etc) during primary training. I doubt they practice it much in 767s, though, despite the fact that they actually glide better. :)
  - chmars 10y ago
    You usually don't practice gliding when learning how to fly a small aircraft, they simply don't glide very well. What you of course do are power-off landings – on airfields, for example from the downwind, and simulated, i.e., you make a go-around just before landing, outside an airfield. Sometimes, it works, sometimes, it doesn't, there are many factors … that's why you actually fly with power idle and not with power off. There're still a few incidents, i.e., somehow the practice becomes tool real! All in all, power-off landings and other emergency training are an important part of becoming a pilot but you don't spend that much time for them. Other things are much more time-consuming in a typical 45-hour syllabus.
  - plafl 10y ago
    Related fact: the glide ratio does not depend on the aircraft weight, only on the aerodynamic efficiency (the ratio between your lift and your drag), so it is useless to throw weight to reach further like maybe you have seen sometimes on movies. Less weight will make you descend slower but not further. Normally, the longer your wing, the higher your efficiency. See for example the pictures here: https://en.wikipedia.org/wiki/Aspect_ratio_(aeronautics) https://en.wikipedia.org/wiki/Aspect_ratio_(aeronautics)
DonaldFisk 10y ago
The reason he had to side-slip the aircraft was because the RAT doesn't generate enough power to operate the flaps.
- dorfsmay 10y ago
  Why are you saying this? Aren't flaps used to lower stall speed? I have flown gliders at a beginner level (so no flap) and the reason we did side/straight ahead slips was because we came in too high (emergency procedure or bad estimation) and would have ended up touching down too far with not enough space left to land safely.
  - eropple 10y ago
    They are, but as I understand it the RAT doesn't generate enough power to operate the flaps in general once you get down below a certain speed.
  - FabHK 10y ago
    Flaps do lower the stall speed, but they also make the glide ratio worse, so you descend more steeply.
    - dorfsmay 10y ago
      But that is a side effect of flaps. So what you are saying is that they had planned their pattern assuming they would be able to extend flap on final but couldn't and ended up too high? I assumed they came in a bit too high as an insurance (you can burn height but can invent it), but just ended up with a lot more than they expected just because if their lack if familiarisation with the situation in that plane, so much that the dive break alone weren't sufficient to burn it.
      - FabHK 10y ago
        Yes, typically you'd want to come in a bit high (or fast; you can always trade speed for altitude to an extent). Then, you put in flaps to have a less efficient wing profile and descent more steeply (without gaining excessive speed). However, here they did not have enough power to do that, so the Captain put it into a slip: flying uncoordinated, with (say) left rudder, but right aileron, flying somewhat diagonally (or rather, flying straight ahead still towards the runway, but presenting not only the nose, but a bit of the aircraft body to the wind). That gets you down quite well. Those are really the techniques when you're too high on the approach: 1. Flaps 2. Slip 3. S-Turns
ryan-allen 10y ago
I couldn't believe the suspension! What a feat landing that plane.
- lultimouomo 10y ago
  Landing the plane was incredible, but having the plane take off without enough fuel was outright negligence. I'm pretty sure the airline industry is more keen to have pilots who follow procedures and avoid risks in the first place than heroes that miracolously solve trouble they created. Not that the pilot was the only one responsible off course, but he had his share of blame in the whole thing.
  - qwertyuiop924 10y ago
    They did follow procedures, actually...
sandworm101 10y ago
I question why a plane was allowed off the ground without a working fuel level sensor(s). Budget isnt allowed to rent cars without one. Forget the conversion errors. What if there had been a fuel leak? [1] That a plane ran out of fuel so quickly, leaving no powered landing options, speaks very badly of the regulatory regime of the time. [1] There is another famous canadian "glider" story involving a jet over the atlantic. All i remember is that the pilot was a former bush pilot who ignored his instuments, refusing to believe he had a fuel leak.
- rtkwe 10y ago
  Man it'd be convenient if that was covered in the linked article... > Pearson consulted the master minimum equipment list (MMEL), which indicated that the aircraft was not legal to fly with blank fuel gauges but due to a misunderstanding, Pearson believed that it was safe to fly if the amount of fuel was confirmed with measuring sticks.[14] > The 767 was still a very new aircraft, having flown its maiden flight in September 1981. C-GAUN was the 47th Boeing 767 off the production line, and had been delivered to Air Canada less than four months previously.[15] In that time period there had been 55 changes to the MEL, and some pages were blank pending development of procedures. > Because of this unreliability, it had become practice for flights to be authorized by maintenance personnel. To add to his own misconceptions about the condition the aircraft had been flying in since the previous day, reinforced by what he saw in the cockpit, Pearson now had a signed-off maintenance log that it had become custom to prefer over the MEL. [0] [0]: https://en.wikipedia.org/wiki/Gimli_Glider https://en.wikipedia.org/wiki/Gimli_Glider
  - sandworm101 10y ago
    And there was no reg in place for someone to slap a big 'unfit for flight' sticker on the door. That passengers were allowed to board is totally unacceptable.
    - rtkwe 10y ago
      In so far as such a regulation actually exists it's the MMEL list that was partially ignored because the procedures were in such flux on a new plane.

boterock 10y ago

why do you do [0] and never put any [0]() =(

vic-traill 10y ago
CS man! What can I say? :-)
- ythn 10y ago
  No, he means, where's the reference? I would be like if I said: Scientists recently proved the existence of a soul inside of all life forms [0].
  - vic-traill 10y ago
    Well played, sir!
- nkozyra 10y ago
  Every CS paper I've had to write required valid references [1]
qwertyuiop924 10y ago
Indeed. Unterminated references are a sure sign of sloppy thinking[0]. They can also be dangerous[1]: gaze into the void, and the void gazes back. Cast into void, and you might get a null pointer exception.

sova 10y ago

Wait, Canada converted from Imperial to Metric? Wow that's amazing! I wish the US would do the same.

deleted 10y ago
[deleted]
auxym 10y ago
Only 3 countries in the entire world have not adopted SI units.
- techdragon 10y ago
  Actually Liberia and Myanmar have been converting to Metric, so the USA is likely the last place where people are not being taught Metric. Unless it's improved and Metric is being taught in American schools?
  - learc83 10y ago
    Metric has been taught in most American schools since the 70s. Nearly everyone here learned it at some point, but most people don't use it day to day, so they don't think in it.
    - Shivetya 10y ago
      yeah but its not like its pushed much outside of chemistry. my niece and nephew have learned less about it than I did over thirty years ago. it simply is not a priority, it could be slowly slipped into prominence by emphasizing the measurements on everyday items instead of making those in small print
      - learc83 10y ago
        >yeah but its not like its pushed much outside of chemistry Every science class I had in high school used metric. We also spent a fair amount of time going through it in elementary and middle school math classes. My younger sister (by 20 years) spent a good deal of time on the metric system in her math classes.

caconym_ 10y ago

IIRC they put a few other aircrews into the same scenario in simulators, and they all crashed. I think what the crew accomplished here is one of the most impressive and inspiring human feats I've ever heard of; more people should be familiar with the story. Like, sure, Pearson had glider experience... but he applied that experience flawlessly in an aircraft with a brick-like glide ratio, landing with no slats or flaps, all the while losing control authority as the airspeed dropped and made the RAT less and less effective, with 69 human lives at stake. Holy shit. For anyone who's interested, Wikipedia is full of these stories of disasters and near-disasters, and they make for interesting reading.

jsight 10y ago
A glide ration of 12:1 is not great, but isn't exactly brick-like either. A Cessna 172 has a glide ratio of about 9:1. Pilots spend a lot of time practicing gliding in airplanes like that (Cessnas, Pipers, etc) during primary training. I doubt they practice it much in 767s, though, despite the fact that they actually glide better. :)
- chmars 10y ago
  You usually don't practice gliding when learning how to fly a small aircraft, they simply don't glide very well. What you of course do are power-off landings – on airfields, for example from the downwind, and simulated, i.e., you make a go-around just before landing, outside an airfield. Sometimes, it works, sometimes, it doesn't, there are many factors … that's why you actually fly with power idle and not with power off. There're still a few incidents, i.e., somehow the practice becomes tool real! All in all, power-off landings and other emergency training are an important part of becoming a pilot but you don't spend that much time for them. Other things are much more time-consuming in a typical 45-hour syllabus.
- plafl 10y ago
  Related fact: the glide ratio does not depend on the aircraft weight, only on the aerodynamic efficiency (the ratio between your lift and your drag), so it is useless to throw weight to reach further like maybe you have seen sometimes on movies. Less weight will make you descend slower but not further. Normally, the longer your wing, the higher your efficiency. See for example the pictures here: https://en.wikipedia.org/wiki/Aspect_ratio_(aeronautics) https://en.wikipedia.org/wiki/Aspect_ratio_(aeronautics)

DonaldFisk 10y ago

The reason he had to side-slip the aircraft was because the RAT doesn't generate enough power to operate the flaps.

dorfsmay 10y ago
Why are you saying this? Aren't flaps used to lower stall speed? I have flown gliders at a beginner level (so no flap) and the reason we did side/straight ahead slips was because we came in too high (emergency procedure or bad estimation) and would have ended up touching down too far with not enough space left to land safely.
- eropple 10y ago
  They are, but as I understand it the RAT doesn't generate enough power to operate the flaps in general once you get down below a certain speed.
- FabHK 10y ago
  Flaps do lower the stall speed, but they also make the glide ratio worse, so you descend more steeply.
  - dorfsmay 10y ago
    But that is a side effect of flaps. So what you are saying is that they had planned their pattern assuming they would be able to extend flap on final but couldn't and ended up too high? I assumed they came in a bit too high as an insurance (you can burn height but can invent it), but just ended up with a lot more than they expected just because if their lack if familiarisation with the situation in that plane, so much that the dive break alone weren't sufficient to burn it.
    - FabHK 10y ago
      Yes, typically you'd want to come in a bit high (or fast; you can always trade speed for altitude to an extent). Then, you put in flaps to have a less efficient wing profile and descent more steeply (without gaining excessive speed). However, here they did not have enough power to do that, so the Captain put it into a slip: flying uncoordinated, with (say) left rudder, but right aileron, flying somewhat diagonally (or rather, flying straight ahead still towards the runway, but presenting not only the nose, but a bit of the aircraft body to the wind). That gets you down quite well. Those are really the techniques when you're too high on the approach: 1. Flaps 2. Slip 3. S-Turns

ryan-allen 10y ago

I couldn't believe the suspension! What a feat landing that plane.

lultimouomo 10y ago
Landing the plane was incredible, but having the plane take off without enough fuel was outright negligence. I'm pretty sure the airline industry is more keen to have pilots who follow procedures and avoid risks in the first place than heroes that miracolously solve trouble they created. Not that the pilot was the only one responsible off course, but he had his share of blame in the whole thing.
- qwertyuiop924 10y ago
  They did follow procedures, actually...

sandworm101 10y ago

I question why a plane was allowed off the ground without a working fuel level sensor(s). Budget isnt allowed to rent cars without one. Forget the conversion errors. What if there had been a fuel leak? [1] That a plane ran out of fuel so quickly, leaving no powered landing options, speaks very badly of the regulatory regime of the time. [1] There is another famous canadian "glider" story involving a jet over the atlantic. All i remember is that the pilot was a former bush pilot who ignored his instuments, refusing to believe he had a fuel leak.

rtkwe 10y ago
Man it'd be convenient if that was covered in the linked article... > Pearson consulted the master minimum equipment list (MMEL), which indicated that the aircraft was not legal to fly with blank fuel gauges but due to a misunderstanding, Pearson believed that it was safe to fly if the amount of fuel was confirmed with measuring sticks.[14] > The 767 was still a very new aircraft, having flown its maiden flight in September 1981. C-GAUN was the 47th Boeing 767 off the production line, and had been delivered to Air Canada less than four months previously.[15] In that time period there had been 55 changes to the MEL, and some pages were blank pending development of procedures. > Because of this unreliability, it had become practice for flights to be authorized by maintenance personnel. To add to his own misconceptions about the condition the aircraft had been flying in since the previous day, reinforced by what he saw in the cockpit, Pearson now had a signed-off maintenance log that it had become custom to prefer over the MEL. [0] [0]: https://en.wikipedia.org/wiki/Gimli_Glider https://en.wikipedia.org/wiki/Gimli_Glider
- sandworm101 10y ago
  And there was no reg in place for someone to slap a big 'unfit for flight' sticker on the door. That passengers were allowed to board is totally unacceptable.
  - rtkwe 10y ago
    In so far as such a regulation actually exists it's the MMEL list that was partially ignored because the procedures were in such flux on a new plane.