US Standard Atmosphere, 1976
As published by NOAA, NASA, and USAF
The standard atmosphere is mathematically defined in six layers from sea level to 71 km.
|
Layer |
Name |
Lower Altitude (km) |
Upper Altitude (km) |
Upper Altitude (ft) |
|
1 |
Troposphere |
0 |
11 |
36,089 |
|
2 |
Stratosphere |
11 |
20 |
65,618 |
|
3 |
- |
20 |
32 |
104,987 |
|
4 |
- |
32 |
47 |
154,199 |
|
5 |
- |
47 |
51 |
167,323 |
|
6 |
Mesosphere |
51 |
71 |
232,940 |
h = altitude above sea level in feet or meters.
T0 = Absolute temperature at sea level = 288.15 K = 518.67 R (or 15° C = 59° F)
r0 = Density of air at sea level = 1.225 kg/m3 = 0.07648 lb/ft3 = 0.0023769 slug/ft3
P0 = Standard air pressure at sea level = 1 Atm = 101325 N/m2 = 2116.2 lb/ft2 = 14.696 lb/in2 = 29.921 in of Hg
| # |
Altitudes up to: |
English Units Temperature (R) Density (slug/ft3) Pressure (lb/ft2) |
Metric Units (K) (kg/m3) (N/m2) |
| h is measured in: | feet | meters | |
| 1 |
11 km |
T = T0 (1 – h / 145442 ft) r = r0 (1 – h / 145442 ft)4.255876 P = P0 (1 – h / 145442 ft) 5.255876 |
T = T0 (1 – h / 44329 m) r = r0 (1 – h / 44329 m) 4.255876 P = P0 (1 – h / 44329 m) 5.255876 |
| 2 |
20 km |
T = T0 (0.751865) r = r0 (0.297076)e((36089-h)/20806) P = P0 (0.223361)e((36089-h)/20806) |
T = T0 (0.751865) r = r0 (0.297076)e((10999-h)/6341.4) P = P0 (0.223361)e((10999-h)/6341.4) |
| 3 |
32 km |
T = T0 (0.682457 + h/945374) r = r0 (0.978261 + h/659515)-35.16319 P = P0 (0.988626 + h/652600)-34.16319 |
T = T0 (0.682457 + h/288136) r = r0 (0.978261 + h/201010)-35.16319 P = P0 (0.988626 + h/198903)-34.16319 |
| 4 |
47 km |
T = T0 (0.482561 + h/337634) r = r0 (0.857003 + h/190115)-13.20114 P = P0 (0.898309 + h/181373)-12.20114 |
T = T0 (0.482561 + h/102906) r = r0 (0.857003 + h/57944)-13.20114 P = P0 (0.898309 + h/55280)-12.20114 |
| 5 |
51 km |
T = T0 (0.939268) r = r0 (0.00116533)e((154200-h)/25992 P = P0 (0.00109456)e((154200-h)/25992 |
T = T0 (0.939268) r = r0 (0.00116533)e((46998-h)/7922 P = P0 (0.00109456)e((46998-h)/7922 |
| 6 |
71 km |
T = T0 (1.434843 – h/337634) r = r0 (0.79899 – h/606330)11.20114 P = P0 (0.838263 – h/577922)12.20114 |
T = T0 (1.434843 – h/102906) r = r0 (0.79899 – h/184800)11.20114 P = P0 (0.838263 – h/176142)12.20114 |
Conversion factors:
Length: 1 m = 3.281 ft
Temperature: R = 1.8 K K = °C + 273.16 R = °F + 459.69 °F=1.8 °C + 32
Density: 1 slug/ft3 = 515.38 kg/m3
Pressure: 1 lb/ft2 = 47.88 N/m2