Sid Boyce wrote: > > There was a 757 over Canada that lost both engines (source Reader's > Digest in my doctor's office some years ago) The famous "Gimli Glider", and there are far better reports, such as one from Air and Space, I think.
They had a strong feeling they were low on fuel during the flight because their airspeed and fuel consumption didn't add up. (The engines have their own fuel flow rate meters, which were not affected, and they were watching them closely due to the fuel uncertainty.) The only explanation was that there were some 10 - 20 thousand Lbs light on fuel. This was also the first Air Canada plane ordered with all metric instruments, and the pilots had never fueled a plane in Liters and Kgs. I believe they had even reported to ATC that they might have insufficient fuel before the engines started to quit. they had a moment's notice as the flight engineer noted fluctuations in fuel manifold pressure before the tanks ran dry. Another thing that is left out of the operations manual is the no-engine glide distance. Well, I understand why, to give an absolutely certain answer, you have to FLY the thing with the engines off and windmilling, and unless forced to do so by the FAA, I can understand a flight test pilot being a BIT nervous about such a test schedule. But, without even a guess at the glide range, the pilots were paniced about where they could possibly land. As it turned out, they had a choice of at least 8 major airports, because at cruise altitude, the thing could glide over 100 miles! But, they didn't know that. And, in fact, the on-board fuel computer was still usable, they just didn't know it! Apparently they had a bad sensor on one tank or something, and the fuel computer was showing an error code, which they thought meant no readings were valid. The system apparently was fully redundant, and the readings it reported, based on only one sensor in that tank, had a very high probability of being correct, they just weren't verifiable against the other sensor. All this is from memory, I may have a few details off, but I think what I wrote above captures the gist of it. As for the Heathrow 777 crash, after what was reported to be a 22 hour flight, I can maybe imagine the crew being a bit punchy, but running critically low on fuel ought to start klaxons blaring in the cockpit, so it seems pretty unlikely they could just run out of fuel while blissfully unaware of the condition. Jon ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Flightgear-users mailing list Flightgear-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-users
