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Equation 14 · Part 1 · Flight at the Energy Floor: Transport Selection to 2100

Symbol M

MM
MM

What this part means

M is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Its job in the formula

M is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

The passage around this formula

…and 53.6 for the McDonnell Douglas DC-10 — the direct fuel-efficiency cost of pushing lift-to-drag ratio through the transonic and supersonic regime, exactly the L/D term in the Breguet equation collapsing even as speed M rises [ 11 ] . Its program cost ballooned from an initial 1962 estimate of 70 million pounds to somewhere between 1.5 and 2.1 billion pounds by 1976, with a unit cost of 23 million pounds per aircraft in 1977; against initial predictions of 350 aircraft sold, only 20 were ever built, 14 of them…

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A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.

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