Inputs
Unit System
Metric (International)
English (US)
Standard Sea Level Ratios
Altitude
kilometers [km]
meters [m]
feet [ft]
miles [mi]
nautical miles [NM]
Velocity
kilometers/hour [km/h]
meters/second [m/s]
feet/second [ft/s]
miles per hour [mph]
knots true airspeed [KTAS]
knots calibrated airspeed [KCAS]
knots equivalent airspeed [KEAS]
Mach number [-]
Reference Length
kilometers [km]
meters [m]
centimeters [cm]
inches [in]
feet [ft]
miles [mi]
nautical miles [NM]
Temperature Increment
Kelvin [K]
Celsius [°C]
Fahrenheit [°F]
Rankine [°R]
Results This section requires altitude only
Atmospheric Layer
Geometric Altitude
kilometers [km]
meters [m]
feet [ft]
miles [mi]
nautical miles [NM]
Geopotential Altitude
kilometers [km]
meters [m]
feet [ft]
miles [mi]
nautical miles [NM]
Acceleration of Gravity
kilometers/hour/second [km/h/s]
meters/square-second [m/s²]
feet/square-second [ft/s²]
miles per hour/second [mph/s]
knots/second [kts/s]
gravity ratio, g/g0 [-]
Mean Molecular Weight
kilograms/kilomole [kg/kmol]
pounds/pound mole [lb/lbmol]
molecular weight ratio, M/M0 [-]
Kinetic Temperature
Kelvin [K]
Celsius [°C]
Fahrenheit [°F]
Rankine [°R]
temperature ratio, theta [-]
Molecular Temperature
Kelvin [K]
Celsius [°C]
Fahrenheit [°F]
Rankine [°R]
molecular temperature ratio, TM/TM0 [-]
Pressure
millibars [mbar]
kilopascals [kPa]
pascals [Pa]
newtons/square-meter [N/m²]
pounds/square-foot [lb/ft²]
pounds/square-inch [lb/in²]
atmospheres [atm]
torr [torr]
feet of water [ft of H2O]
inches of mercury [in of Hg]
pressure ratio, delta [-]
Density
grams/cubic-centimeter [g/cm³]
kilograms/cubic-meter [kg/m³]
slugs/cubic-foot [slug/ft³]
pounds-mass/cubic-foot [lb/ft³]
pounds-mass/cubic-inch [lb/in³]
density ratio, sigma [-]
Speed of Sound
kilometers/hour [km/h]
meters/second [m/s]
feet/second [ft/s]
miles per hour [mph]
knots [kts]
speed of sound ratio, a/a0 [-]
Dynamic Viscosity
poise [P]
poiseuille [Pi]
pascals second [Pa·s]
kilograms/meter second [kg/(m·s)]
newtons second/square-meter [(N·s)/m²]
pounds-force second/square-foot [(lbf·s)/ft²]
slugs/foot second [slug/(ft·s)]
pounds-mass/foot second [lb/(ft·s)]
pounds-mass/foot hour [lb/(ft·hr)]
reyn [(lbf·s)/in²]
viscosity ratio, mu/mu0 [-]
Kinematic Viscosity
lentor [St]
stokes [St]
centistokes [cSt]
poise cubic-centimeter/gram [(P·cm³)/g]
square-meters/second [m²/s]
square-feet/second [ft²/s]
kinematic viscosity ratio, eta/eta0 [-]
Coefficient of Thermal Conductivity
kilocalories/(meter hour °Celsius) [kcal/(m·hr·°C)]
calories/(centimeter second °Celsius) [cal/(cm·s·°C)]
ergs/(centimeter second °Celsius) [erg/(cm·s·°C)]
joules/(meter second Kelvin) [J/(m·s·K)]
watts/(meter °Celsius) [W/(m·°C)]
watts/(meter Kelvin) [W/(m·K)]
BTU/(foot second °Rankine) [BTU/(ft·s·°R)]
BTU/(foot hour °Fahrenheit) [BTU/(ft·hr·°F)]
BTU/(sq-foot second °Fahrenheit)/inch [BTU/(ft²·s·°F)/in]
BTU/(sq-foot hour °Fahrenheit)/inch [BTU/(ft²·hr·°F)/in]
thermal conductivity ratio, kappa/kappa0 [-]
Pressure Scale Height
kilometers [km]
meters [m]
feet [ft]
miles [mi]
nautical miles [NM]
Density Scale Height
kilometers [km]
meters [m]
feet [ft]
miles [mi]
nautical miles [NM]
Total Number Density
/cubic-meter [/m³]
/cubic-centimeter [/cm³]
/cubic-inch [/in³]
/cubic-foot [/ft³]
number density ratio, N/N0 [-]
Mole Volume
cubic-meters/kilomole [m³/kmol]
cubic-feet/pound mole [ft³/lbmol]
mole volume ratio, vm/vm0 [-]
Mean Air Particle Speed
kilometers/hour [km/h]
meters/second [m/s]
feet/second [ft/s]
miles per hour [mph]
knots [kts]
particle speed ratio, V/V0 [-]
Mean Collision Frequency
/hour [/h]
/minute [/min]
/second [/s]
collision frequency ratio, nu/nu0 [-]
Mean Free Path
kilometers [km]
meters [m]
centimeters [cm]
inches [in]
feet [ft]
miles [mi]
nautical miles [NM]
mean free path ratio, L/L0 [-]
This section requires altitude and velocity
True Airspeed
kilometers/hour [km/h]
meters/second [m/s]
feet/second [ft/s]
miles per hour [mph]
knots true airspeed [KTAS]
Calibrated Airspeed
kilometers/hour [km/h]
meters/second [m/s]
feet/second [ft/s]
miles per hour [mph]
knots calibrated airspeed [KCAS]
Equivalent Airspeed
kilometers/hour [km/h]
meters/second [m/s]
feet/second [ft/s]
miles per hour [mph]
knots equivalent airspeed [KEAS]
Airspeed Compressibility Correction
kilometers/hour [km/h]
meters/second [m/s]
feet/second [ft/s]
miles per hour [mph]
knots [kts]
Mach Number
Equivalent Mach Number
True Dynamic Pressure
millibars [mbar]
kilopascals [kPa]
pascals [Pa]
newtons/square-meter [N/m²]
pounds/square-foot [lb/ft²]
pounds/square-inch [lb/in²]
atmospheres [atm]
torr [torr]
feet of water [ft of H2O]
inches of mercury [in of Hg]
Compressible Dynamic Pressure
millibars [mbar]
kilopascals [kPa]
pascals [Pa]
newtons/square-meter [N/m²]
pounds/square-foot [lb/ft²]
pounds/square-inch [lb/in²]
atmospheres [atm]
torr [torr]
feet of water [ft of H2O]
inches of mercury [in of Hg]
Total Head
millibars [mbar]
kilopascals [kPa]
pascals [Pa]
newtons/square-meter [N/m²]
pounds/square-foot [lb/ft²]
pounds/square-inch [lb/in²]
atmospheres [atm]
torr [torr]
feet of water [ft of H2O]
inches of mercury [in of Hg]
Critical Pressure Coefficient (Cp,cr )
Vacuum Pressure Coefficient (Cp,min )
Laminar Recovery Temperature
Kelvin [K]
Celsius [°C]
Fahrenheit [°F]
Rankine [°R]
Turbulent Recovery Temperature
Kelvin [K]
Celsius [°C]
Fahrenheit [°F]
Rankine [°R]
Total Temperature
Kelvin [K]
Celsius [°C]
Fahrenheit [°F]
Rankine [°R]
Reynolds Number / Unit Length
/kilometer [/km]
/meter [/m]
/centimeter [/cm]
/inch [/in]
/foot [/ft]
/mile [/mi]
/nautical mile [/NM]
This section requires altitude, velocity, and reference length
Reynolds Number
Laminar Boundary Layer Thickness
kilometers [km]
meters [m]
centimeters [cm]
inches [in]
feet [ft]
miles [mi]
nautical miles [NM]
Laminar Displacement Thickness
kilometers [km]
meters [m]
centimeters [cm]
inches [in]
feet [ft]
miles [mi]
nautical miles [NM]
Laminar Coefficient of Friction (Cf )
Turbulent Boundary Layer Thickness
kilometers [km]
meters [m]
centimeters [cm]
inches [in]
feet [ft]
miles [mi]
nautical miles [NM]
Turbulent Displacement Thickness
kilometers [km]
meters [m]
centimeters [cm]
inches [in]
feet [ft]
miles [mi]
nautical miles [NM]
Turbulent Coefficient of Friction (Cf )
