The rules that use the vocabulary item "aa" are:

<i_f_v-sing>

mixed aa fcr

mixed aa fire control radar

swa mixed aa fcr

swa mixed aa fire control radar

<i_f_v-pl>

mixed aa fcrs

mixed aa fire control radars

swa mixed aa fcrs

swa mixed aa fire control radars

<i_f_v>

mixed aa fcr

mixed aa fcrs

mixed aa fire control radar

mixed aa fire control radars

swa mixed aa fcr

swa mixed aa fcrs

swa mixed aa fire control radar

swa mixed aa fire control radars