proj CaptChem
read tanker.gf

LBP 0, 95f
variable L
set L={FP} plus {AP} div 2
LBP {FP}, {L}, {AP} 
smod 1E5/5.0

`Light ship:
WEIGHT  1.015085 @-100.9681 , 
 20.3017 @-98.39809 , 
 34.51291 @-88.4981 , 
 28.42239 @-88.39809 , 
 28.42239 @-25.49809 , 
 32.48273 @-25.39809 , 
 32.48273 @-9.498089 , 
 44.66375 @-9.398089 , 
 20.3017 @-.5000898  0  6.501701 

`Added weights
ADD"Crew and Effects  " 4 -1  0  11.5  /MAX 4 
ADD"Engine Room Spares" 15 -8  0  2  /MAX 15 
ADD"Bosun's Stores    " 8 -91.3  0  10.5  /MAX 8 
ADD"Hoses and Fittings" 6 -25.88  0  9.899998 

`Tanks as loaded:
PART WBDB2.S | LOAD  .1 | CONT SW
PART WBDB2.P | LOAD  .1 | CONT SW
PART WBDB3.S | LOAD  1  | CONT SW
PART WBDB3.P | LOAD  1 | CONT SW
PART CGC3.C | LOAD  .83 | CONT "LINSEED" .934 
PART CGC4.C | LOAD  .83 | CONT "BENZENE" .879 
PART CGS3.S | LOAD  .025 |CONT FW 
PART FOSET.P | LOAD  .98 | CONT "FUEL OIL" .87 
PART FODAY.P | LOAD  .98 | CONT "FUEL OIL" .87 
PART DODBER.S | LOAD  .98 | CONT "DIESEL OIL" .75 
PART DODBER.P | LOAD  .98 | CONT "DIESEL OIL" .75 
PART DODAY.S | LOAD  .98 | CONT "DIESEL OIL" .75 
PART LOSYS.C | LOAD  .98 | CONT "LUBE OIL" .924 
PART LOSTO.S | LOAD  .98 | CONT "LUBE OIL" .924 
PART FW.S | LOAD  1 | CONT FW 
PART FW.P | LOAD  1 | CONT FW 

macro drafts `drafts taken by crew (except the bad one at 55f)
 draft 4.04 @ FP,
 4.06 @ 85f,
 4.15 @ 75f,
 4.14 @ 65f,
 4.20 @ MP,
 4.21 @ 35f,
 4.23 @ 25f,
 4.28 @ 15f,
 4.34 @ AP
/
.drafts
`Weights to correct draft & trim:
deflect 0
add "Aft growth" 5.0, 0, 0, {FVCG}
add "Fwd growth" DELTA, ?, ?, {FVCG}

\LS prediction in the condition when the draft survey was done
ls /notab
wait

report
.drafts
page
status fixed, tanks:tot, displ
disk intermediate.dat /holdreport

variable (le) permsag=0.03 `this is the permanent sag to be accounted for

`Make added weight "Sagger" to correct deflection 
`with a tapered distribution in order to avoid changing shear much
variable (we) sagger=1 `initial guess at peak tons/meter
variable (le) HL=30 `half length of distribution
variable (le) L1, L2
macro sagger
 set L1={FLCG} minus {HL}, L2={FLCG} plus {HL}
 add "Sagger" 0 @ {L1}, {sagger} @ {FLCG}, 0 @ {L2}, 0, {FVCG} /nowarn
 .drafts
 deflect {permsag}
 solve weight, lcg
/

variable (le) ds
variable q

macro matchdefl
.sagger
ls /notab
set DRLOC8={MP}
set ds={deflect} minus {permsag} `want ds to be zero
set q={ds} times 70 plus 1 `simple correction based on ds
set sagger={sagger} times {q} 
\  ds: {ds:3} q: {q:4}  sagger: {sagger:3}
/
.matchdefl (9) `try it 9 times to bring ds down to zero
.drafts
solve weight, lcg

`Check result:
disk off
ls /notab
status fixed, tanks:tot, displ
page
ls /notab:plotonly /profile
print preview /thick:3
report off