ISAtmosphere

International Standard Atmospheric (ISA) model

Only metric units are used.

Functions

• T_K Atmospheric temperature [K]

• p_Pa Air pressure [Pa]

• ρ_kg_m³ Air density [kg/m³]

• a_m_s Speed of sound [m/s]

• Vcas2Vtas True airspeed Vtas [m/s] as a function of the calibrated airspeed Vcas [m/s]

• Vtas2Vcas Calibrated airspeed Vcas [m/s] as a function of the True airspeed Vtas [m/s]

• M2Vtas True airspeed Vtas [m/s] as a function of the Mach number

• Vtas2M Mach as a function of the True airspeed Vtas [m/s]

• M2Vcas Calibrated airspeed Vcas [m/s] as a function of the Mach number

• Vtas2M Mach as a function of the True airspeed Vtas [m/s]

• Hp_trans_m Transition altitude [m]

• conditions returns AtmosConditions

• θ temperature ratio

• δ pressure ratio

• σ density ratio

Constants

• T₀_K Standard atmospheric temperature [K] at Mean Sea Level (MSL)
• p₀_Pa Standard atmospheric pressure [Pa] at Mean Sea Level (MSL)
• ρ₀_kg_m³ Standard atmospheric density [kg/m³] at Mean Sea Level (MSL)
• a₀_m_s Speed of sound [m/s] at Mean Sea Level (MSL)
• g₀_m_s² Graviation acceleration [m/s²]
• Hp_trop_m Geopotential pressure altitude [m] of Tropopause

Type

• AtmosConditions: Hp_m, T_K, p_Pa, ρ_kg_m³, a_m_s

Source: EUROCONTROL BADA 4 User Manual Chapter 2.2 Atmosphere Model