Altimeter having temperature correction
AssigneeFlytec AG
InventorsErich Lerch, Peter Joder
Life of this patent
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Abstract
According to the invention, a climate-related, or to be precise, a temperature-related correction of the altitude reading is carried out on an altimeter. In doing this, the measurement of altitude is based on an average reference temperature value at sea level and on an average air pressure reference value at sea level according to the U.S. Standard Atmosphere 1976. The correction ensues by altering the reference temperature at sea level. A correction is then carried out when the temperature prevailing at a certain altitude above sea level differs from the temperature reference value for this altitude. This temperature reference value results at sea level based on the average temperature reference value.
Claims12
A method for correcting an altitude reading on an altitude measuring device as a function of climate and/or temperature, the method comprising:
- determining a first altitude based on an average reference temperature value at sea level and an average air pressure reference value at sea level;
- determining as an ambient temperature a temperature at the first altitude determined at the measuring device;
- and
- determining a corrected average reference temperature value by altering the average reference temperature value at sea level to arrive at a corrected altitude reading,
- wherein the average reference temperature value at sea level is 288° K and the average air pressure reference value at sea level is 1013 mb, and the corrected average reference temperature value is determined when the ambient temperature deviates from a reference temperature value for the first altitude, the reference temperature value for the first altitude set with reference to the average reference temperature value.
A method for correcting an altitude reading on an altitude measuring device as a function of climate and/or temperature, the method comprising:
- determining a first altitude based on an average reference temperature value at sea level and an average air pressure reference value at sea level;
- determining as an ambient temperature a temperature at the first altitude determined at the measuring device;
- and
- determining a corrected average reference temperature value by altering the average reference temperature value at sea level to arrive at a corrected altitude reading, wherein the average reference temperature value at sea level is 288° K and the average air pressure reference value at sea level is 1013 mb, and the corrected average reference temperature value is determined when the ambient temperature deviates from a reference temperature value for the first altitude, the reference temperature value for the first altitude set with reference to the average reference temperature value, wherein the determination of the first altitude is based on a pressure of 1013 mb at a temperature of 288° K at sea level in mid latitudes employing the following formula:
- h=((T—MH+ΔT)/0.0065)*(1 −5.255*(p/p_O)**0.5)
- where T_MH=the reference temperature value at sea level =288° K, and where ΔT =+6° C. when the ambient temperature is higher than the reference temperature value, and ΔT=−6° C. when the ambient temperature is lower than the reference temperature value and ΔT=0 when the ambient temperature corresponds to the reference temperature value forthe first altitude.
Dependencies are inferred from the claim text.