Energy spectrum and arrival direction of primary cosmic rays of energy above 10 to the 18th power eV

The observation of ultra high energy cosmic rays with 20 sq km array has started at Akeno. The preliminary results on energy spectrum and arrival direction of energies above 10 to the 18th eV are prsented with data accumulated for four years with the 1 sq km array, for two years with the 4 sq km array and for a half year with the new array. The energy spectrum is consistent with the previous experiments showing the flattening above 10 to the 18.5 eV.