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Equation 3 · Part 1 · Flight at the Energy Floor: Transport Selection to 2100

Symbol M

MM
MM

What this part means

cruise Mach number.

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.

Where the article explains it

where a is the local speed of sound, M is cruise Mach number, g is standard gravity, cTc_T is thrust-specific fuel consumption, L/D is the lift-to-drag ratio, and W1W_1 and W2W_2 are the aircraft’s weight at the start and end of the cruise segment [ 1 ] .

The passage around this formula

where a is the local speed of sound, M is cruise Mach number, g is standard gravity, cTc_T is thrust-specific fuel consumption, L/D is the lift-to-drag ratio, and W1W_1 and W2W_2 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 —…

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Learn the underlying idea

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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