whumpa-whumpa-whumpa-whumpa

sound of a helicopter. Also: ‘whop whop whop’
wuppa wuppa’
whup-whup-whup’
flac-flac-flac’
chakk-chackk-chak-chak, chak-a-chak-akk-chk-chk-chk’
DUBDUBDUBDUBDUBDUBDUB’
THITH-THITH-THITH’
batabatabatabata’
ÔtocotocotocotocoÕ