What the Gimli Glider link doesn't mention is that the 767 that glided into Gimli had no functioning vertical speed indicator so judging rate of descent and planning a descent profile was extemely difficult. So using this incident to judge the 767s gliding capability probably won't give an accurate figure. However, anyone unfortunate enough to use a 767 as a glider would probably be in a similar predicament and unable to judge descent rate. In fact the 767 was dropping much faster than Cpt. Pearson and F/O Quintal expected when at 9500ft Winnepep informed them that they still had 35 nm to go(to Winnepeg, the planned emergency destination).
I remember a story about a British Airways 747 (G-BDXH) that lost all engines (!) over Java in Indonesia in 1982. It had flown through a volcanic ash cloud, which resulted in all engines shutting down. They glided a fair distance before they got them running again. They landed safely in Jakarta and needles to say, the flight crew had lots of medals thrown at them for that one. It was a night time incident, so an unpowered descent and landing would have been disasterous.
The following comes from the investigation's recordings of the radio exchanges from this incident.(the 747s callsign was Speedbird 9):
Speedbird 9: "Mayday, Mayday, Mayday, Speedbird 9, our position is 100 Miles south of Halim (one of Jakarta's airports). We have lost all four engines. We're descending and we're out of flight level 370."
Silence for a few moments...then
Air Traffic Control: "Jakarta, Speedbird 9, have you got a problem?"
Speedbird 9: Speedbird 9 (said carefully and slowly) we have lost all four engines, we are descending and we are out of level 360."
Another pause...
ATC:" Speedbird 9 understand you have lost number 4 engine?"
At this point, Captain Greaves (piloting the 747) turned to his co-pilot and said, " The F@*k Wit doesn't understand!"
Speedbird 9: (trying to control his frustration) Jakarta, Speedbird 9, (spoken very clearly and distinctly) we have lost ALL four engines, repeat ALL four engines. Now descending through flight level 350"
The Jakarta controller was still unable to understand but fortunately a Garuda Indonesian Airways flight on the same frequency interupted the exchange:
Garuda 875: "Jakarta, Garuda 875, Speedbird 9 has lost all four engines, he's lost ALL four engines."
At last Jakarta had got the message and Captain Greaves could get on with the matter in hand.
Oh the joys of international flying.
KD