Air Density & RAD Meter

Air Density & RAD Meter works out air density and 8 readings that follow from it: density altitude, relative air density (RAD), relative horsepower, dyno correction factor, actual pressure at your altitude, altimeter setting (QNH), dew point and virtual temperature. Density comes from the full CIPM equation, with the compressibility factor and water vapour pressure: the formula used in metrology, not an ideal-gas shortcut. Use it for jetting, comparing dyno sheets, flying, precision shooting or tuning a model engine. WHERE THE DATA COMES FROM · From the nearest weather station: using your location, the app brings in temperature, pressure and humidity, and takes the altitude from the GPS. · Or by hand, offline: the whole calculation runs on the phone. THE TWO SCREENS · Results: the reading you watch most, large, and the rest below. Tap any of them to feature it; the app remembers. · Weather: temperature, sea-level pressure (QNH), humidity and altitude, with the station at the top. If a value falls outside the range, the app tells you instead of keeping quiet. DYNO CORRECTION 3 standards: SAE J1349, SAE J607 and DIN 70020. Pick the one on your dyno sheet: they are not interchangeable. UNITS AND RANGES · Temperature in °F or °C, from −40 to 60 °C. · Pressure in inHg, mmHg, mb or hPa, from 500 to 1500 mb. · Altitude in feet or metres, from −500 to 10,000 m. · Density in lb/ft³, lb/gal (US) or kg/m³. 10 languages and dark mode. PERMISSIONS · Location, optional, only to find the nearest station. Without it you type the data in and the app works just the same. · Internet, to query that station. Your position is sent to the ISEnet service rounded to about 100 m, and nothing else leaves the phone: no ads, no analytics. MORE FROM US Under "More apps" you'll find our jetting apps for karts and dirt bikes, and Kart Chassis Setup.