aero

This module contains a set of standard aerodynamic functions and constants used in aeronautics.

Constants

BlueSky tools contains some useful aeronautic constants:

• kts = 0.514444 (m/s of 1 knot)
• ft = 0.3048 (m of 1 foot)
• fpm = ft/60 (feet per minute)
• inch = 0.0254 (m of 1 inch)
• sqft = 0.09290304 (m of 1 square feet)
• nm = 1852. (m of 1 nautical mile)
• lbs = 0.453592 (kg of 1 pound mass)
• g0 = 9.80665 (m/s^2 Sea level gravity constant)
• R = 287.05287 (Used in wikipedia table: checked with 11000 m)
• p0 = 101325. (Pa Sea level pressure ISA)
• rho0 = 1.225 (kg/m^3 Sea level density ISA)
• T0 = 288.15 (K Sea level temperature ISA)
• Tstrat = 216.65 (K Stratosphere temperature (until alt= 22km))
• gamma = 1.40 (cp/cv: adiabatic index for air)
• gamma1 = 0.2 ((gamma-1)/2 for air)
• gamma2 = 3.5 (gamma/(gamma-1) for air)
• beta = -0.0065 ([K/m] ISA temp gradient below tropopause)
• Rearth = 6371000. (m average earth radius)
• a0 = np x sqrt(gamma x R x T0) (sea level speed of sound ISA)

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Functions

The aerodynamic functions in this module include:

• Computing the speed of sound [m/s] for a given altitude [m]. This can be done by calling the function vvsound()
• Computing the air density for a given altitude. This can be done by calling the function vdensity()

Conversions

In addition, the module contains some useful speed conversion tools.

• True airspeed [m/s] to Mach number [-] conversion (mach2tas)
• Equivalent airspeed [m/s] to true airspeed [m/s] (eas2tas)
• True airspeed [m/s] to equivalent airspeed [m/s] (tas2eas)
• Calibrated airspeed [m/s] to true airspeed [m/s] (cas2tas)
• True airspeed [m/s] to calibrated airspeed [m/s] (tas2cas)
• Mach number [-] to calibrated airspeed [m/s] (mach2cas)
• Calibrated airspeed [m/s] to mach number [-] (cas2mach)
• Meters [m] to feet [ft] (meters_to_feet_rounded)
• Metric speed [m/s] to knots [kts] (metric_spd_knots_rounded)