Hi

You all might want to read the story below about the Gimli Glider.

http://www.flightsafety.org.au/articles/t0357.php

Here's an extract from the above.

Cheers...Chris

The flight from Montreal to Edmonton, including a brief stop in Ottawa,
required 22,300kg of fuel, an amount expressed as mass because of the
importance of knowing an aircraft's weight.

The mechanics needed to work out how many litres made up 22,300kg. They
could then subtract the 7,682 litres already in the tanks, and use the
fuel gauge on the refueling truck to tell when they had reached the
right number of litres to make up 22,300kg.

But the 767 was the first aircraft in Air Canada's fleet to use metric
units (kilograms) rather than imperial (pounds). Metric units were being
phased in across Canada, and the conversions were still causing confusion.

With the help of First Officer Quintal, the ground crew used the correct
procedure to calculate the weight in kilos. However, they had not been
trained in correct conversion, so the figure of 1.76 provided by the
refueling company on their refueling document, was taken to be the
required multiplier. It was typical of the numbers seen on previous
slips and they assumed that the numbers provided over the previous few
months had indicated specific gravity in the new metric system.

They decided to multiply 7,682 by 1.76. This would mean 13,597kg
remained in the tanks, requiring an infusion of 8,703kg to bring the
fuel level up to 22,300kg. They then divided 8,703kg by 1.76, assuming
that this conversion would give them the correct volume in litres.
Through this calculation, the crew determined that 4,916 litres needed
to be added from the fuel truck.

The problem was that 1.77 is the multiplier that converts litres into
pounds, not kilograms: to convert litres into kilograms you need to
multiply by 0.8. Flight 143 did not have 22,300kg on board, it had about
10,000kg, less than half the amount of A-1 kerosene jet fuel needed to
get the aircraft to Edmonton. The refueller didn't know where the flight
was headed, so no alarm bells rang for him as he poured fuel into the tanks.

Using a computer to calculate fuel also caused confusion over
responsibilities. In the past, when fuel was calculated manually, a
flight engineer's duties included checking the fuel load. Flight
engineers were a thing of the past on this 767, as a Presidential task
force, under Ronald Reagan, had determined that aircraft could be built
to be operated by two pilots instead of three, if the tasks previously
given to the second officer (flight engineer) were either fully
automated or handled by ground staff.

Responsibility for ensuring adequate fuelling had passed to the
maintenance branch. But because these men were not trained to calculate
fuel, they assumed the pilots would make sure it was done properly.
The problem was neither of the pilots was trained in this technical
task. Safety procedures had failed to keep pace with new technology.

As the investigation later concluded: 'Air Canada ... neglected to
assign clearly and specifically the responsibility for calculating the
fuel load in an abnormal situation.'

The investigation attacked Air Canada's training procedures, noting
'both flight crew and maintenance personnel seemed to be somewhat
mesmerised by the complex, computerised characteristics of the 767. They
did not appear to have sufficient background knowledge of these aspects
of the aircraft. They did not appear to have received sufficient
training about some of the critical aircraft systems, in particular, the
fueling system.'