function [CyB_b,CyB_v,CyB]=CyB2(TVT,Gam_w,S_v,S_w,Lamq_v,Z_w,d,AR_w,k_v,CLa_v,CyB_v_wbh_eff,CyB_v_eff)

CyB_w=-.0001*abs(Gam_w); %eqn 7.2

%CyB_b can't be determined
CyB_b=-2.1;

if TVT==0
%single vertical tail
sbn=.724+3.06*(S_v/S_w)/(1+cos(Lamq_v))+.4*Z_w/d+.009*AR_w; %eqn 7.5
CyB_v=-k_v*CLa_v*sbn*(S_v/S_w) %eqn 7.4
else
%twin vertical tails
CyB_v=-2*CyB_v_wbh_eff*CyB_v_eff * S_v/S_w; %eqn 7.7
end

CyB=CyB_w+CyB_b+CyB_v;	%eqn 7.1