Equation 13 · Part 2 · Flight at the Energy Floor: Transport Selection to 2100
Symbol D
What this part means
D 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
D is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Full expression→Symbol D→Article meaning
The passage around this formula
Concorde is the clearest case in transport history of a regulatory filter, not an economic one, capping a technology’s addressable market. The aircraft cruised at Mach 2.02, carried between 92 and 128 passengers, and burned roughly 4,800 US gallons of fuel per hour at cruise, delivering about 15.8 passenger-miles per gallon against 33.3 for the Boeing 707, 46.4 for the 747, 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…
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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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Sources cited in the surrounding passage
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