`Finding the angle theta3, where A2 = A1 as in the RINA Cargo Loss criterion.

proj theta3
read sv
report
draft 3
vcg 3
solve weight lcg

macro findt3
macro t3
lim(1) res ratio from abs {t1} to abs {t3} > 1
ra /lim /noprint
if {limmarg}>0 then set t3={t3} minus {t} else set t3={t3} plus {t}
set t={t} times 0.6
if {t} > 0.05 then exit t3
//
variable t3=30
variable t
set t={t3} div 2
lim off
.t3
\\Theta3 is {t3:1} degrees, as demonstrated below.\
\
ra 0 5 ... 30 /lim:att
/

tcg=-0.75 `Simulate hook load on port side
solve
variable t1={heel}
tcg=0 `Load dropped

.findt3

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end