Читать книгу Flight Theory and Aerodynamics - Joseph R. Badick - Страница 52

To provide a basis for comparing aircraft performance at different parts of the world and under varying atmospheric conditions, the performance data must be reduced to a set of standard conditions. These are defined by the International Civil Aviation Organization (ICAO) and are compiled in a standard atmosphere table. An abbreviated table is shown here as Table 2.1. Columns in the table show standard day density, density ratio, pressure, pressure ratio, temperature, temperature ratio, and speed of sound at various altitudes.

Table 2.1 Standard atmosphere table

Altitude (ft)	Density ratio, σ		Pressure ratio, δ	Temperature (°F)	Temperature ratio, θ	Speed of sound (kts.)	Kinematic viscosity, v (ft2/s)
0	1.0000	1.0000	1.0000	59.00	1.0000	661.7	0.000 158
1 000	0.9711	0.9854	0.9644	55.43	0.9931	659.5	0.000 161
2 000	0.9428	0.9710	0.9298	51.87	0.9862	657.2	0.000 165
3 000	0.9151	0.9566	0.8962	48.30	0.9794	654.9	0.000 169
4 000	0.8881	0.9424	0.8637	44.74	0.9725	652.6	0.000 174
5 000	0.8617	0.9283	0.8320	41.17	0.9656	650.3	0.000 178
6 000	0.8359	0.9143	0.8014	37.60	0.9587	647.9	0.000 182
7 000	0.8106	0.9004	0.7716	34.04	0.9519	645.6	0.000 187
8 000	0.7860	0.8866	0.7428	30.47	0.9450	643.3	0.000 192
9 000	0.7620	0.8729	0.7148	26.90	0.9381	640.9	0.000 197
10 000	0.7385	0.8593	0.6877	23.34	0.9312	638.6	0.000 202
15 000	0.6292	0.7932	0.5643	5.51	0.8969	626.7	0.000 229
20 000	0.5328	0.7299	0.4595	−12.32	0.8625	614.6	0.000 262
25 000	0.4481	0.6694	0.3711	−30.15	0.8281	602.2	0.000 302
30 000	0.3741	0.6117	0.2970	−47.98	0.7937	589.5	0.000 349
35 000	0.3099	0.5567	0.2353	−65.82	0.7594	576.6	0.000 405
36 089a	0.2971	0.5450	0.2234	−69.70	0.7519	573.8	0.000 419
40 000	0.2462	0.4962	0.1851	−69.70	0.7519	573.8	0.000 506
45 000	0.1936	0.4400	0.1455	−69.70	0.7519	573.8	0.000 643
50 000	0.1522	0.3002	0.1145	−69.70	0.7519	573.8	0.000 818

^a The tropopause.