I write this program on TC.
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// PROGRM Heli_500.C

#include stdio.h
#include math.h

void main(void)
{
double f11,f12,f13,f14 ; // Force rotor
double f21,f22,f23,f24 ; // Force rotor ( 2/3 )( Kg )
double d1,d2,d3,d4; // Diameter rotor ( Metr )
double v1,v2,v3,v4; // Speed line blade ( Metr/sek )
double v; // U motor ( V )
double a,a1; // I motor ( A )
double w; // Power motor ( Wt )
double wk; // Efficiency motor ( % )
double kpd; // Efficiency main gearbox ( % )
double kpdx; // Efficiency tail gearbox ( % )
double cy; // Cy - const. lifting force = 0.6
double ro; // Ro - const. = 1/8
double r1,r2,r3,r4; // Radius rotor ( M )
double h; // Width blade ( M ) 44(mm)=0.044(M)
double w1,w2,w3,w4; // Speed rotation ( Rad./sec. )
double n1,n2,n3,n4; // Number turn main rotor ( turn/min.)
double nm; // Number turn motor ( turn/min.)
double re1,re2,re3,re4; // Give number gearbox

d1=0.9; d2=1.0; d3=1.1; d4=1.2; // SPEED 500
// d1=0.50;d2=0.51;d3=0.52;d4=0.53; // Speed 400

v=7.7; a=12.0; a1=21.0; // SPEED 500
// v=9.0; a=5.0; a1=16.0; // Speed 400

wk=0.745; // SPEED 500
// wk=0.68; // Speed 400
kpd=0.95*0.95*0.99*0.99*0.99*0.99*0.99;// SPEED 500
// kpd=0.95*0.99*0.99*0.99; // SPEED 400
kpdx=0.87; // SPEED 500
// kpdx=1.0; // Speed 400
h=0.044; // SPEED 500
// h=0.037; // Speed 400
cy=0.6;
ro=0.125;
r1=d1/2;r2=d2/2;r3=d3/2;r4=d4/2;

printf("Programa for HELI - Motor SPEED 500.\n");
printf("Efficiency motor= %2.3f\n",wk);

printf("Efficiency main gearbox= %2.3f Efficiency tail gearbox=
%2.3f\n",kpd,kpdx);

printf(" Wt V A Diamete(M)=%2.2f Diamete(M)=%2.2f
Diamete(M)=%2.2f Diam=%2.2f\n",d1,d2,d3,d4);

for(a;a {
w=v*a;
f11=(20*d1*w*wk/736)*kpd*kpdx ;
f12=(20*d2*w*wk/736)*kpd*kpdx ;
f13=(20*d3*w*wk/736)*kpd*kpdx ;
f14=(20*d4*w*wk/736)*kpd*kpdx ;

f21=exp(log(f11)*2/3); // Force rotor ( Kg )
f22=exp(log(f12)*2/3); // Force rotor ( Kg )
f23=exp(log(f13)*2/3); // Force rotor ( Kg )
f24=exp(log(f14)*2/3); // Force rotor ( Kg )

printf(" %3.0f %3.2f %3.2f Fors(Kg) = %2.2f Fors(Kg) = %2.2f Fors
(Kg) = %2.2f Fors=%2.2f\n",w,v,a,f21,f22,f23,f24);

v1=sqrt((2*f21)/(cy*ro*0.5*h*r1)); // Speed line blade.
w1=v1/r1; // Speed rotation ( Rad./sec. )
n1=9.5*w1; // Number turn main rotor ( turn/min.)
nm=21140.0-(282.4*(a-10.0)); // Number turn motor SPEED 500
// nm=15261.0-(262.7*(a-3.0)); // Number turn motor Speed 400
re1=nm/n1 ; // Give number gearbox
v2=sqrt((2*f22)/(cy*ro*0.5*h*r2));
w2=v2/r2;
n2=9.5*w2;
re2=nm/n2;
v3=sqrt((2*f23)/(cy*ro*0.5*h*r3));
w3=v3/r3;
n3=9.5*w3;
re3=nm/n3;
v4=sqrt((2*f24)/(cy*ro*0.5*h*r4));
w4=v4/r4;
n4=9.5*w4;
re4=nm/n4;

printf(" Gearbox =%6.2f Gearbox =%6.2f Gearbox
=%6.2f Ge=%6.2f\n",re1,re2,re3,re4);
} ;
};


I am receive good result calculate.
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