1013 -1003 = 10hPa x 30 = 300ft. Altitude
in ISA conditions = 15,700ft.
FL160 ISA = +15oC – (2o x 16) = -17oC
OAT = -27oC
Dev. = -10oC
Difference between true altitude and pressure altitude is calculated as:
4ft per1,000ft per oC ISA deviation = 4 x 15.7 x 10 = 628ft
True altitude = 15,700 – 628 =
15,072. Or use CRP5