Equation 9 · Part 2 · Flight at the Energy Floor: Transport Selection to 2100
Symbol W_2
What this part means
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
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 W_2→Article meaning
The passage around this formula
where a is the local speed of sound, M is cruise Mach number, g is standard gravity, is thrust-specific fuel consumption, L/D is the lift-to-drag ratio, and and are the aircraft’s weight at the start and end of the cruise segment [ 1 ] . Three of those four factors — speed, engine efficiency, and aerodynamic efficiency — are where a century of aeronautical engineering has already done most of its work and where further gains now come in single-digit…
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Sources cited in the surrounding passage
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