The International Standard Atmosphere (ISA) is a mathematical model which provides a vertical distribution of averaged atmospheric properties such as air Temperature, Pressure, Density and Viscosity. Starting from an input altitude, this application computes mean air properties according to the last revision of U.S. Standard Atmosphere 1976, as determined by ISOs TC 20/SC 6 technical committee. The 1976 model is identical with the earlier 1962 standard up to 51 km, and the International Civil Aviation Organization (ICAO) standard up to 32 km.
Standard Atmosphere model’s main function is to provide common reference conditions that can be used for aircraft design and performance calculation purposes as well as for Computational Fluid Dynamics (CFD) simulations. Therefore this app can be useful to aeronautical and aerospace engineers as well as to CFD operators and pilots performing rough and preliminary calculations.
Key features:
• Universal iPhone/iPad app
• Modern interface optimized for every devices display
• 3 different measurement systems including International System (SI), Imperial System (EN) and US Customary System (US)
• 3 different gravitational models:
- Constant
- Geopotential
- WGS84
• It allows to choose non standard conditions by manually setting sea level temperature and pressure.
• It provides air properties up to the end of Mesosphere (84,852m or 278,385ft)
• It provides full explanation of embedded mathematical and physical models and formulas
Pro features:
• It allows the user to export computed data results via email in a well formatted table
• It uses GPS to find the current latitude in order to properly enable the WGS84 model
• When an internet connection is available it allows the user to retrieve local weather condition in order to automatically set non standard current condition at sea level
• It allows to compute further values such as:
- Geopotential, Geometric and Pressure altitudes
- Static, Dynamic, Total, Impact and Compressible Impact Pressure
- Static and Total Density and Temperature
- ISA offset and Ram Rise
- True, Equivalent and Calibrated Air Speed
- Mach angle
- Reynolds Number
- Friction coefficient and boundary layers thickness for both laminar and turbulent boundary layers
- Pressure, Density and Temperature Total Ratios
• You can choose among TAS, EAS and CAS input speed
• The CAS algorithm computes accurate results for both subsonic and supersonic flows (Saint-Venant formula for subsonic speeds and Lord Rayleigh formula solved iteratively with the Newton-Raphson method for supersonic ones)
Disclaimer:
Please note that this software is NOT intended to replace certified and official data and it has NOT to be used for performing flight.