Mod A, 2011-01-25
Standard 1976 atmosphere.
Based on tables built for iOS app, "FlightMechanic", by Bruce Jackson dated 2010-08-07.
Data hand-entered from Table I: Geometric Altitude, Metric Units, p53ff
Used equation 3.6 on page 48 for relationship between temperature and speed-of-sound
MS 132 NASA, Hampton, VA 23681
Added xmlns="http://www.w3.org/1998/Math/MathML" to
<math> elements as required.
Sea level pressure in lb/ft2
Bias value of deg Rankine at 0 deg Farenheit; needed to calculate speed of sound from temperature
Convert input altitude, in feet, to meters, for function independent value
Output from table is metric
Output from table, but only used locally to calculate ambient pressure output
Direct output from table without conversion
Calculated from ambient temperature using equation 3.6 from REF02
C equivalent:
*v_sound_fps = 49.02*pow(t_amb_F + DEGR_AT_0_DEGF,0.5);
Convert table output, in deg C, to deg F
Converts the ambient pressure ratio found in the tables (p_p0) to English units
by multiplying by standard ambient sea level pressure (SEA_LEVEL_PRESSURE_psf)
Geometric altitude, Z, breakpoint set in meters
-1000.0, -500.0, 0.0, 1000.0, 1500.0, 2000.0, 2500.0, 3000.0, 3500.0, 4000.0, 4500.0,
5000.0, 5500.0, 6000.0, 6500.0, 7000.0, 7500.0, 8000.0, 8500.0, 9000.0, 9500.0, 10000.0,
10500.0, 11000.0, 11100.0, 12000.0, 13000.0, 14000.0, 15000.0, 16000.0, 17000.0, 18000.0,
19000.0, 20000.0, 20100.0, 21000.0, 22000.0, 23000.0, 24000.0, 25000.0, 26000.0, 27000.0,
28000.0, 29000.0, 30000.0, 31000.0, 32000.0, 33000.0, 34000.0, 35000.0, 36000.0, 37000.0,
38000.0, 39000.0, 40000.0, 41000.0, 42000.0, 43000.0, 44000.0, 45000.0, 46000.0, 47400.0,
48000.0, 50000.0, 51000.0, 51500.0, 52000.0, 53000.0, 54000.0, 55000.0, 56000.0, 57000.0,
58000.0, 59000.0, 60000.0, 61000.0, 62000.0, 63000.0, 64000.0, 65000.0, 66000.0, 67000.0,
68000.0, 69000.0, 70000.0, 71000.0, 72000.0, 73000.0, 74000.0, 75000.0, 76000.0, 77000.0,
78000.0, 79000.0, 80000.0, 81000.0, 82000.0, 83000.0, 84000.0, 85000.0, 85500.0
1976 atmosphere table I ambient temperatures in degrees C
21.501, 18.250, 15.000, 8.501, 5.252, 2.004, -1.244, -4.491, -7.737, -10.984, -14.229,
-17.474, -20.719, -23.963, -27.207, -30.450, -33.693, -36.935, -40.176, -43.417, -46.658,
-49.898, -53.137, -56.376, -56.500, -56.500, -56.500, -56.500, -56.500, -56.500, -56.500,
-56.500, -56.500, -56.500, -56.463, -55.569, -54.576, -53.583, -52.590, -51.598, -50.606,
-49.614, -48.623, -47.632, -46.641, -45.650, -44.660, -42.177, -39.407, -36.637, -33.686,
-31.100, -28.332, -25.566, -22.800, -20.036, -17.272, -14.509, -11.747, -8.986, -6.225,
-2.500, -2.500, -2.500, -2.500, -2.741, -4.119, -6.873, -9.626, -12.379, -15.131, -17.882,
-20.632, -23.381, -26.129, -28.876, -31.623, -34.369, -37.114, -39.858, -42.601, -45.343,
-48.085, -50.825, -53.565, -56.304, -58.887, -60.842, -62.797, -64.751, -66.704, -68.657,
-70.609, -72.560, -74.511, -76.462, -78.411, -80.360, -82.309, -84.257, -85.230
1976 atmosphere table I ambient pressure ratios (relative to sea level)
1.1244e+00, 1.0607e+00, 1.0000e+00, 8.8700e-01, 8.3453e-01, 7.8461e-01, 7.3715e-01,
6.9204e-01, 6.4920e-01, 6.0854e-01, 5.6997e-01, 5.3341e-01, 4.9878e-01, 4.6600e-01,
4.3499e-01, 4.0567e-01, 3.7798e-01, 3.5185e-01, 3.2720e-01, 3.0397e-01, 2.8210e-01,
2.6153e-01, 2.4219e-01, 2.2403e-01, 2.2053e-01, 1.9145e-01, 1.6362e-01, 1.3985e-01,
1.1953e-01, 1.0217e-01, 8.7340e-02, 7.4663e-02, 6.3829e-02, 5.4570e-02, 5.3721e-02,
4.6671e-02, 3.9945e-02, 3.4215e-02, 2.9328e-02, 2.5158e-02, 2.1597e-02, 1.8553e-02,
1.5950e-02, 1.3722e-02, 1.1813e-02, 1.0177e-02, 8.7743e-03, 7.5727e-03, 6.5473e-03,
5.6708e-03, 4.9200e-03, 4.2758e-03, 3.7220e-03, 3.2452e-03, 2.8338e-03, 2.4784e-03,
2.1709e-03, 1.9042e-03, 1.6728e-03, 1.4615e-03, 1.2962e-03, 1.0877e-03, 1.0095e-03,
7.8735e-04, 6.9536e-04, 6.5349e-04, 6.1401e-04, 5.4156e-04, 4.7705e-04, 4.1969e-04,
3.6873e-04, 3.2353e-04, 2.8348e-04, 2.4803e-04, 2.1671e-04, 1.8907e-04, 1.6470e-04,
1.4325e-04, 1.2441e-04, 1.0786e-04, 9.3372e-05, 8.0688e-05, 6.9607e-05, 5.9942e-05,
5.1526e-05, 4.4210e-05, 3.7861e-05, 3.2373e-05, 2.7642e-05, 2.3569e-05, 2.0067e-05,
1.7060e-05, 1.4481e-05, 1.2274e-05, 1.0387e-05, 8.7761e-06, 7.4028e-06, 6.3421e-06,
5.2410e-06, 4.3985e-06, 4.0269e-06
1976 atmosphere table I density ratios (relative to sea level)
1.0996e+00, 1.0489e+00, 1.0000e+00, 9.0748e-01, 8.6376e-01, 8.2168e-01, 7.8119e-01,
7.4225e-01, 7.0482e-01, 6.6885e-01, 6.3432e-01, 6.0117e-01, 5.6936e-01, 5.3887e-01,
5.0964e-01, 4.8165e-01, 4.5485e-01, 4.2921e-01, 4.0470e-01, 3.8128e-01, 3.5891e-01,
3.3756e-01, 3.1720e-01, 2.9780e-01, 2.9332e-01, 2.5464e-01, 2.1763e-01, 1.8601e-01,
1.5898e-01, 1.3589e-01, 1.1616e-01, 9.9304e-02, 8.4894e-02, 7.2580e-02, 7.1439e-02,
6.1808e-02, 5.2661e-02, 4.4903e-02, 3.8317e-02, 3.2722e-02, 2.7965e-02, 2.3917e-02,
2.0470e-02, 1.7533e-02, 1.5029e-02, 1.2891e-02, 1.1065e-02, 9.4474e-03, 8.0714e-03,
6.9089e-03, 5.9248e-03, 5.0902e-03, 4.3809e-03, 3.7769e-03, 3.2618e-03, 2.8216e-03,
2.4447e-03, 2.1216e-03, 1.8440e-03, 1.6051e-03, 1.3993e-03, 1.1581e-03, 1.0749e-03,
8.3827e-04, 7.4033e-04, 6.9637e-04, 6.5765e-04, 5.8605e-04, 5.2164e-04, 4.6376e-04,
4.1180e-04, 3.6521e-04, 3.2348e-04, 2.8615e-04, 2.5280e-04, 2.2303e-04, 1.9650e-04,
1.7288e-04, 1.5188e-04, 1.3323e-04, 1.1670e-04, 1.0206e-04, 8.9118e-05, 7.7690e-05,
6.7616e-05, 5.8747e-05, 5.0917e-05, 4.3938e-05, 3.7866e-05, 3.2589e-05, 2.8009e-05,
2.4039e-05, 2.0603e-05, 1.7632e-05, 1.5068e-05, 1.2857e-05, 1.0954e-05, 9.3178e-06,
7.9134e-06, 6.7099e-06, 6.1747e-06
Table lookup for ambient temperature; returns ambient temperature in degrees C
(in variable t_amb_C) based on input value of Z_m (geometric altitude, meters)
using the breakpoint values in Z_m_pts and the table defined in T_dgC_table.
Table lookup for pressure ratio; returns ambient pressure normalized with SL pressure
(in variable p_p0) based on input value of Z_m (geometric altitude, meters)
using the breakpoint values in Z_m_pts and the table defined in P_P0_table.
Table lookup for density ratio; returns density normalized with SL density
(in variable sigma) based on input value of Z_m (geometric altitude, meters)
using the breakpoint values in Z_m_pts and the table defined in sigma_table.
GeometricAltitude
ft
0
AmbientTemperature
dgF
59
0.4
AmbientPressure
lbf_ft2
2116.22
2.5
RatioOfDensityToSeaLevel
nd
1
0.002
GeometricAltitude
ft
5000
AmbientTemperature
dgF
41.2
0.4
AmbientPressure
lbf_ft2
1761.12
2.5
RatioOfDensityToSeaLevel
nd
0.8616
0.002
GeometricAltitude
ft
10000
AmbientTemperature
dgF
23.36
0.4
AmbientPressure
lbf_ft2
1455.84
2.5
RatioOfDensityToSeaLevel
nd
0.73866
0.002
GeometricAltitude
ft
15000
AmbientTemperature
dgF
5.55
0.4
AmbientPressure
lbf_ft2
1194.336
2.5
RatioOfDensityToSeaLevel
nd
0.6292
0.002
GeometricAltitude
ft
20000
AmbientTemperature
dgF
-12.3
0.4
AmbientPressure
lbf_ft2
972.576
2.5
RatioOfDensityToSeaLevel
nd
0.5328
0.002
GeometricAltitude
ft
25000
AmbientTemperature
dgF
-30.2
0.4
AmbientPressure
lbf_ft2
785.376
2.5
RatioOfDensityToSeaLevel
nd
0.4481
0.002
GeometricAltitude
ft
30000
AmbientTemperature
dgF
-48
0.4
AmbientPressure
lbf_ft2
628.416
2.5
RatioOfDensityToSeaLevel
nd
0.3741
0.002
GeometricAltitude
ft
35000
AmbientTemperature
dgF
-65.8
0.4
AmbientPressure
lbf_ft2
497.952
2.5
RatioOfDensityToSeaLevel
nd
0.3099
0.002
GeometricAltitude
ft
40000
AmbientTemperature
dgF
-69.7
0.4
AmbientPressure
lbf_ft2
391.68
2.5
RatioOfDensityToSeaLevel
nd
0.2462
0.002
GeometricAltitude
ft
45000
AmbientTemperature
dgF
-69.7
0.4
AmbientPressure
lbf_ft2
308.016
2.5
RatioOfDensityToSeaLevel
nd
0.1936
0.002
GeometricAltitude
ft
50000
AmbientTemperature
dgF
-69.7
0.4
AmbientPressure
lbf_ft2
242.208
2.5
RatioOfDensityToSeaLevel
nd
0.1522
0.002
GeometricAltitude
ft
55000
AmbientTemperature
dgF
-69.7
0.4
AmbientPressure
lbf_ft2
192.24
2.5
RatioOfDensityToSeaLevel
nd
0.12082
0.002
GeometricAltitude
ft
60695.53806
AmbientTemperature
dgF
-69.7
0.4
AmbientPressure
lbf_ft2
146.0890153
2.5
RatioOfDensityToSeaLevel
nd
9.1816E-02
0.002
GeometricAltitude
ft
67257.21785
AmbientTemperature
dgF
-68.9188
0.4
AmbientPressure
lbf_ft2
106.7865774
2.5
RatioOfDensityToSeaLevel
nd
6.6981E-02
0.002
GeometricAltitude
ft
73818.89764
AmbientTemperature
dgF
-65.3422
0.4
AmbientPressure
lbf_ft2
78.22818852
2.5
RatioOfDensityToSeaLevel
nd
4.8623E-02
0.002
GeometricAltitude
ft
80380.57743
AmbientTemperature
dgF
-61.7692
0.4
AmbientPressure
lbf_ft2
57.47865142
2.5
RatioOfDensityToSeaLevel
nd
3.5405E-02
0.002
GeometricAltitude
ft
86942.25722
AmbientTemperature
dgF
-58.198
0.4
AmbientPressure
lbf_ft2
42.35825952
2.5
RatioOfDensityToSeaLevel
nd
2.5859E-02
0.002
GeometricAltitude
ft
93503.93701
AmbientTemperature
dgF
-54.6286
0.4
AmbientPressure
lbf_ft2
31.30524246
2.5
RatioOfDensityToSeaLevel
nd
1.8943E-02
0.002
GeometricAltitude
ft
100065.6168
AmbientTemperature
dgF
-51.0628
0.4
AmbientPressure
lbf_ft2
23.20223608
2.5
RatioOfDensityToSeaLevel
nd
1.3918E-02
0.002
GeometricAltitude
ft
103018.3727
AmbientTemperature
dgF
-49.4572
0.4
AmbientPressure
lbf_ft2
20.29560791
2.5
RatioOfDensityToSeaLevel
nd
1.2126E-02
0.002
GeometricAltitude
ft
106299.2126
AmbientTemperature
dgF
-46.912
0.4
AmbientPressure
lbf_ft2
17.50240913
2.5
RatioOfDensityToSeaLevel
nd
1.0393E-02
0.002
GeometricAltitude
ft
109580.0525
AmbientTemperature
dgF
-41.9242
0.4
AmbientPressure
lbf_ft2
15.11637108
2.5
RatioOfDensityToSeaLevel
nd
8.8688E-03
0.002
GeometricAltitude
ft
112860.8924
AmbientTemperature
dgF
-36.9364
0.4
AmbientPressure
lbf_ft2
13.07866284
2.5
RatioOfDensityToSeaLevel
nd
7.5829E-03
0.002
GeometricAltitude
ft
116141.7323
AmbientTemperature
dgF
-31.9522
0.4
AmbientPressure
lbf_ft2
11.33553243
2.5
RatioOfDensityToSeaLevel
nd
6.4956E-03
0.002
GeometricAltitude
ft
119422.5722
AmbientTemperature
dgF
-26.968
0.4
AmbientPressure
lbf_ft2
9.84148111
2.5
RatioOfDensityToSeaLevel
nd
5.5745E-03
0.002
GeometricAltitude
ft
122703.4121
AmbientTemperature
dgF
-21.9874
0.4
AmbientPressure
lbf_ft2
8.558416924
2.5
RatioOfDensityToSeaLevel
nd
4.7926E-03
0.002
GeometricAltitude
ft
125984.252
AmbientTemperature
dgF
-17.0068
0.4
AmbientPressure
lbf_ft2
7.454808194
2.5
RatioOfDensityToSeaLevel
nd
4.1277E-03
0.002
GeometricAltitude
ft
129265.0919
AmbientTemperature
dgF
-12.028
0.4
AmbientPressure
lbf_ft2
6.503990548
2.5
RatioOfDensityToSeaLevel
nd
3.5611E-03
0.002
GeometricAltitude
ft
132545.9318
AmbientTemperature
dgF
-7.0492
0.4
AmbientPressure
lbf_ft2
5.68310881
2.5
RatioOfDensityToSeaLevel
nd
3.0774E-03
0.002
GeometricAltitude
ft
135826.7717
AmbientTemperature
dgF
-2.074
0.4
AmbientPressure
lbf_ft2
4.973328622
2.5
RatioOfDensityToSeaLevel
nd
2.6638E-03
0.002
GeometricAltitude
ft
139107.6115
AmbientTemperature
dgF
2.8994
0.4
AmbientPressure
lbf_ft2
4.358566712
2.5
RatioOfDensityToSeaLevel
nd
2.3095E-03
0.002
GeometricAltitude
ft
142388.4514
AmbientTemperature
dgF
7.8728
0.4
AmbientPressure
lbf_ft2
3.825490894
2.5
RatioOfDensityToSeaLevel
nd
2.0055E-03
0.002
GeometricAltitude
ft
145669.2913
AmbientTemperature
dgF
12.8444
0.4
AmbientPressure
lbf_ft2
3.362461958
2.5
RatioOfDensityToSeaLevel
nd
1.7441E-03
0.002
GeometricAltitude
ft
152230.9711
AmbientTemperature
dgF
22.7804
0.4
AmbientPressure
lbf_ft2
2.60824115
2.5
RatioOfDensityToSeaLevel
nd
1.3251E-03
0.002
GeometricAltitude
ft
160761.1549
AmbientTemperature
dgF
27.5
0.4
AmbientPressure
lbf_ft2
1.886715941
2.5
RatioOfDensityToSeaLevel
nd
9.4920E-04
0.002
GeometricAltitude
ft
175524.9344
AmbientTemperature
dgF
17.1338
0.4
AmbientPressure
lbf_ft2
1.075801599
2.5
RatioOfDensityToSeaLevel
nd
5.5299E-04
0.002
GeometricAltitude
ft
188648.294
AmbientTemperature
dgF
-2.6626
0.4
AmbientPressure
lbf_ft2
0.640981876
2.5
RatioOfDensityToSeaLevel
nd
3.4377E-04
0.002
GeometricAltitude
ft
205052.4934
AmbientTemperature
dgF
-27.3928
0.4
AmbientPressure
lbf_ft2
0.325114879
2.5
RatioOfDensityToSeaLevel
nd
1.8434E-04
0.002
GeometricAltitude
ft
221456.6929
AmbientTemperature
dgF
-52.0852
0.4
AmbientPressure
lbf_ft2
0.158629735
2.5
RatioOfDensityToSeaLevel
nd
9.5490E-05
0.002
GeometricAltitude
ft
237860.8924
AmbientTemperature
dgF
-75.757
0.4
AmbientPressure
lbf_ft2
0.074099443
2.5
RatioOfDensityToSeaLevel
nd
4.7307E-05
0.002
GeometricAltitude
ft
254265.0919
AmbientTemperature
dgF
-93.6994
0.4
AmbientPressure
lbf_ft2
0.033269095
2.5
RatioOfDensityToSeaLevel
nd
2.2259E-05
0.002
GeometricAltitude
ft
270669.2913
AmbientTemperature
dgF
-110.8948
0.4
AmbientPressure
lbf_ft2
0.014379292
2.5
RatioOfDensityToSeaLevel
nd
1.0105E-05
0.002