Gauge altitude

Gauge, altitude A pressure gauge which displays the force per unit area in terms of the height of a column of a named liquid required to exert that force. 

Altitude Diving Correction Factors Atmospheric Pressure Gauge Altitude (m) Pressure Correction Factor (atm) (m) ... 

The inlet pressures listed in the table are gauge pressures the pressures used in the calculations of j and f are absolute pressures. Thus, atmospheric pressure had already been accounted for in the inlet pressure. The outlet pressure is taken as standard atmospheric pressure. As an example, for a measured gauge pressure of 137.9 kPa (20 psig), the ratio Pjabs/P0 is 2.361. The actual value of the atmospheric pressure will vary day to day, and with altitude thus if an exact value for j or f is desired, local pressure measurements must be made. 

A student pilot takes off from an airport at sea level, and flies to an airport that is 1000 ft above sea level, (a) As the pilot enters the traffic pattern 1000 ft above ground level at the destination airport, what would an air pressure gauge aboard the plane read Assume an air temperature of 15°C and an atmospheric pressure of 1 atm at sea level, (b) The plane altimeter is a gauge that senses pressure and translates the pressure value to an altitude readout. Suppose that during the flight, the atmospheric pressure at sea level in the region increases to 1.02 atm. If the pilot does not correct for this, at what altitude will he or she enter the traffic pattern ... 

One such is Venera 4, launched on June 12, 1967. It reached the planet on October 18 and dropped an instrument package containing two thermometers, a barometer, a radio altimeter, an atmospheric density gauge, 11 gas analyzers, and two radio transmitters. Data collected by these instruments were transmitted to the space vehicle "bus parked in orbit around the planet and then sent on back to Earth. After completing the transmission, the bus deployed a parachute to reduce its speed. It then descended into the Venusian atmosphere to an altitude of 15.51 miles (24.96 km), at which point communications were lost. 

A pitot-static tube is used to measure an airplane s airspeed. When the pressure-difference gauge reads 0.3 psig, how fast is the plane going (a) at sea level where the air density is about 0.075 Ibm/ft and (6) at an altitude of 10,000 ft where the air density is about 0.057 Ibm/ft ... 

Calculate What is your actual diving depth if your depth gauge reads 18 m, but you are at an altitude of 1800 m and your gauge does not compensate for altitude ... 

The table shows the pressure gauge correction factor for high altitude underwater diving. 

Note Absolute pressure in a container is the reading of a pressure gauge plus the local atmospheric pressure which is affected by the local atmosphere and altitude. The generally accepted standard for atmospheric pressure is 14.696 psi (101.325 kPa) at sea level. For approximate purposes, the pressure addition to gauge pressure may be rounded to 15 psi. 

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