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Old 30th Jun 2008, 12:58
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Screwballs
 
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With the caveat that this is all more or less on the back of a very small cigarette packet...

Using the Boeing QRH and some basic maths I achieved a rough figure of 21.3 kilograms burned if you touchdown at a groundspeed of 145 knots, using 74% reverse (detent 1) and autobrake 3 to slowdown. That gives you just shy of twenty seconds to get to 60 knots where you would normally go back to idle reverse. All based on a 737NG.

If you use idle reverse, with the reverse adder, to get to the same 60 knot point you would burn circa 8.2 kilograms.

So a difference of 13.1 kilograms. Very rough maths but I would say I can't be out massively! So in my end of the business, 13.1 X 1000 sectors per day = 13.1 tonnes of Jet A-1.

Jet Fuel Price Monitor

Using the above that could be a saving of $17,218 or £8,648 in real money per day.

All of the above based on a pilot's grasp of mathematics and the venerable Boeing 737-700.
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