Posted on 01/24/2008 8:10:35 AM PST by Clive
Air Canada employees will gather today in Montreal to bid farewell to the infamous Gimli Glider as it embarks on its final journey to the Mojave desert.
It is a graceful end for the storied Boeing 767 that could easily have become the subject of one of the worst aviation disasters in Canadian history were it not for the cool composure of the pilot, Captain Robert Pearson, and his First Officer, Maurice Quintal, 25 years ago. Both will be at the send-off today.
The story of the Gimli Glider began on July 23, 1983, when maintenance crews for Air Canada Flight 143 discovered that a shoddy soldering job had knocked out the computer that calculates how much fuel is needed to get the plane from Montreal to Edmonton, with a brief stopover in Ottawa.
Instead of cancelling the flight, the ground crews decided to do the calculations manually -- triple checking their work to ensure its accuracy. As it turns out, none of the ground crew had ever been trained to do this, but when the aircraft arrived safely in Ottawa, they felt assured of their work.
It was not until a warning signal began beeping at 41,000 feet somewhere over Red Lake, Ont., that the flight crew realized their error -- they had used imperial measurements to calculate how much fuel was needed rather than metric.
The first warning signal indicating that fuel had run out on one engine was followed by a "sharp bong," indicating both engines were out of steam. Because the electrical system was run off the engines, the power was soon knocked out in the cockpit, save for the manual controls, and the plane began plunging at 2,000 feet per minute.
Capt. Pearson was a trained glider pilot and immediately had his first officer begin calculating for the optimum gliding speed for an 80-tonne jumbo jet. After determining they would not make it to Winnipeg, First Officer Quintal suggested taking the plane down at a nearby Air Force base in Gimli, Man., where he once served.
Unbeknownst to the first officer, however, was that one of the airstrips -- where the plane would eventually land -- had become a drag-racing strip. On that day, crowds of campers had collected along the runway to watch go-cart races.
The plane's nose gear eventually came to a stop just 100 feet from where the group had collected, after its front landing gear collapsed on landing.
What could have been a major disaster turned into a miraculous story. The so-called Gimli Glider, having sustained only minor damages, entered back into service just two days later and has continued to fly since. That is until today when it makes its final journey to the so-called "boneyards" of the Mojave desert.
They will just be mothballed, most likely, rather than broken up. They have plenty of life left in them. Air Canada probably is retiring the older airframes, but not replacing them with newer. Eventually they'll be resold to Air Mozambique or some other 2nd or 3rd world country's airline, and fly on.
About 10 years ago I flew from Houston to Merida Mexico on a 737B model flown by a Central American carrier, which one I forget. That was the same model I had made my first airline flight in, on United, around Christmas of 1969.
Yes, the town there is named Gimli, on Lake Winnipeg. Tolkien used Nordic names for some of his characters. The town and the surrounding area there was part of an Icelandic settlement in the late 1800’s. They have an “Icelandic Celebration” there every first weekend of August. I’ve been to it twice. My mom’s family’s roots are in that city.
I flew in the back end of C-47s in 1968. One I was on lost power to the right engine on takeoff from Da Nang. The tower ordered the captain to turn right around and land. The captain said no he was going home. We went straight west a short hop to the mountains where he turned south, cut off the other engine and we glided on the updrafts from the north-south ridgelines 200 kilometers or so back to base at Pleiku. Captain got grounded for a month and toasted in the O-club. The old DC-3 was pretty much a glider with motors anyway.
Yep.
I read recently , I think on FR, that the F4s were engineered with slide rules and were built with extra metal in them because the tolerances were looser than they are now with computers. Now warplanes are made with much closer tolerances because they can be and it makes the planes faster and more maneuverable but shorter lived. There is no margin.
Falling from the sky.
I remember when I was there. My father and I went fishing up near Bissett. Beautiful country.
According to the versions I've read, the only warning the crowd on the ground got was when they saw the thing coming at them. The pilot and co-pilot had no idea anyone would be there until they were close enough to see them and already way past the point where they could make any changes in their landing plan.
The big problem with the recent BA crash landing was that there was no sign of trouble until less than 40 seconds before planned touchdown. In the glider incidents, there was plenty of time to both figure out the nature of the problem and work out details of the plan to get the plane down safety. The Gimli Glider cruised along for about half an hour.
Per new info out from the BA crash investigators today, even after the pilot/co-pilot noted the plane wasn’t maintaining the altitude it was supposed to, and the co-pilot hit the throttle, both engines DID initially respond, followed by partial failure of one a few seconds later and then partial failure of the other a few seconds after that. We’re a week past the incident now, and even the investigators are still flummoxed as to what the heck happened and why. The pilot and co-pilot did an amazing job of instantaneously inventing and executing a response to an unknown situation that was changing every few seconds. As one of them said in an interview afterwards, there are drills for loss of engine power at 30,000 feet, but there are no drills for this. The most likely reason there are no drills for it is that the experienced pilots and engineers who design flight emergency drills couldn’t think of any way to actually salvage a situation like this.
http://uk.reuters.com/article/newsOne/idUKL2490190620080124
“In a second preliminary report, investigators said they were still trying to work out what caused the lack of thrust during the flight’s final moments.
“The engines both initially responded but after about 3 seconds the thrust of the right engine reduced,” the report said. “Some eight seconds later the thrust reduced on the left engine to a similar level.
“The engines did not shut down and both engines continued to produce thrust at an engine speed above flight idle, but less than the commanded thrust.” The reason for the lack of thrust is not yet known. The plane, which was flying on autopilot, was carrying enough fuel.”
Like the man said...”unit cancellation”.
Using unit cancellation, that type of math error is impossible. You can’t use the wrong conversion factor if you practice unit cancellation. Well, you could but if you did you would end up with a number that has units that make no sense whatsoever. You would really have to be an idiot to use a number like that.
Unit cancellation won’t help you out much if you start off with an incorrect constant. The speed of light is 2.99 x 10’8 m/s, if you think it is 6.0 x 10’8 then I don’t care what you do, you’re going to come up with an answer that is way off.
If you use units on your conversion factors, you don’t use the wrong conversion factor. People don’t make up constants. THey look them up and use the wrong one with the wrong units. Or if they write them down in a notebook without the units at all, they don’t know when to use that number and when not to.
Unit cancellation works. It would’ve prevented the mistake in the fuel calcs. If you are so stupid that you make numbers up, then no, units wont help you. Nothing will.
Was Han Solo the pilot?
That was my point, a liter of jet fuel weighs .803 kg (the constant in their equations not accounting for temp), if you mess that up from the get go, then you are pretty much assured an erroneous calculation.
No, he was making the Kessel run in under 12 parsecs. Which would be difficult or at least confusing since a parsec is a unit of distance, not time.
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