True Altitude
When the air is colder than standard your altimeter can mislead you into thinking you are higher than you actually are. Determine true altitude by the following steps:
1.Determine pressure altitude by setting 29.92 momentarily on the altimeter.
2.Set pressure altitude next to outside air tem- perature in the altitude correction window.
3.Subtract station altitude from indicated/cali- brated altitude to determine calibrated alti- tude AGL.
4.Find calibrated altitude AGL on the middle scale and read the correction to station alti- tude on the outer scale.
5.Add the correction to station altitude to get true altitude MSL.
Figure 15
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