The operation used light aircraft and seeded clouds with dry ice, or solid carbon dioxide. His Majesty had personally devised chemical formulae for seeding clouds in the rainmaking process. The first attempt at artificial rainmaking was successful; the clouds turned grey and rain did fall. However, there was no way to ensure that rain fell on a specific area. Then further experiments were carried out in Hua Hin District, Prachuap Khiri Khan Province, with rainfall in target areas.