Altitude (feet)  Rain water content (RWC)(grams, water/ meter3 air) 
0  20.0 
20,000  20.0 
26,300  15.2 
32,700  10.8 
39,300  7.7 
46,000  5.2 

RWC values at other altitudes may be determined by linear interpolation. NOTE : Source of data–Results of the AerospaceIndustries Association(AIA) Propulsion Committee Study, Project PC 338-1, June 1990.
Tab. 95.1 – Certi.cation standard atmospheric rain concentrations
Altitude (feet)  Hail water content (HWC)(grams, water/ meter3 air) 
0  6.0 
7,300  8.9 
8,500  9.4 
10,000  9.9 
12,000  10.0 
15,000  10.0 
16,000  8.9 
17,700  7.8 
19,300  6.6 
21,500  5.6 
24,300  4.4 
29,000  3.3 
46,000  0.2 

HWC values at other altitudes may be determined by linear interpolation.
The hail threat below 7,300 feet and above 29,000 feet is based on linearly
extrapolated data.
NOTE : Source of data–Results of the AerospaceIndustries Association(AIA)
Propulsion Committee(PC) Study, Project PC 338-1, June 1990.

Tab. 95.2 – Certi.cation Standard Atmospheric Hail Concentrations
Rain droplet diameter (mm)  Contribution to total RWC (%) 
0-0.49  0 
0.50-0.99  2.25 
1.00-1.49  8.75 
1.50-1.99  16.25 
2.00-2.49  19.00 
2.50-2.99  17.75 
3.00-3.49  13.50 
3.50-3.99  9.50 
4.00-4.49  6.00 
4.50-4.99  3.00 
5.00-5.49  2.00 
5.50-5.99  1.25 
6.00-6.49  0.50 
6.50-7.00  0.25 
Total  100.00 

Median diameter of rain droplets is 2.66 m/m
NOTE : Source of data–Results of the AerospaceIndustries Association(AIA)
Propulsion Committee(PC) Study, Project PC 338-1, June 1990.

Tab. 95.3 – Certi.cation Standard Atmospheric Rain Droplet Size Distribution

Amdt. 33-19, E.. 4/30/1998
′
Elodie Roux. Septembre 2003
Hail diameter (m/m)  Contribution total HWC (%) 
0-4.9  0 
5.0-9.9  17.00 
10.0-14.9  25.00 
15.0-19.9  22.50 
20.0-24.9  16.00 
25.0-29.9  9.75 
30.0-34.9  4.75 
35.0-39.9  2.50 
40.0-44.9  1.50 
45.0-49.9  0.75 
50.0-55.0  0.25 
Total  100.00 

Median diameter of hail is 16mm
NOTE : Source of data–Results of the AerospaceIndustries Association(AIA)
Propulsion Committee(PC) Study, Project PC 338-1, June 1990.]

Tab. 95.4 – Certi.cation Standard Atmospheric Hail Size Distribution