$ file autosup31.dat  inertia relief example
$ suggested by Timo DeBeer
diag 8
sol 101
include 'autosupa.v707' $
cend
title = tanker under steady static loads		autosup31
echo = both
load = 12
disp = all
oload = all
ese = all
mpcf = all
spcf = all
begin bulk
param, inrel -3 $ auto. distrib. support using rb modes from dynamics
$ bottom surface
grid,	11,	,	0.	-50.	0. $ lh side
=,	*2,	,	*100.	== $
=3 $ to 19
grid,	12,	,	0.	50.	0. $ rh side
=,	*2,	,	*100.	== $
=3
cquad4,	11,	11,	11,	12,	14,	13
=,	*2	*2	*2	*2	*2	*2
=2
$	pid	mid1	t	mid2	12i..	mid3	ts/t  nsm
pshell,	11,	11,	1.	11,	,	,	, 
=,	*2,	== $
=2
pshell,	21,	11,	1.	11 $ no nsm on rest of structure
mat1,	11,	1.+9,	,	.3,	.001 $ bottom material
$ top surface
grid,	21,	,	0.	-50.	100.0 $ lh side
=,	*2,	,	*100.	== $
=3 $ to 29
grid,	22,	,	0.	50.	100. $ rh side
=,	*2,	,	*100.	== $
=3
$ hull
cquad4,	21,	21,	11,	13,	23,	21 $ port
=,	*2	=	*2	*2	*2	*2
=2
cquad4,	22,	21,	12,	14,	24,	22 $ starboard
=,	*2	=	*2	*2	*2	*2
=2
$ bulkheads
cquad4,	31,	21,	11,	21,	22,	12 $ bow
=,	*2	=	*2	*2	*2	*2
=3
$ hatch covers
cquad4,	41,	21,	21,	22,	24,	23 $ bow
=,	*2	=	*2	*2	*2	*2
=2
$antenna
grid,	36,	,	200.	50.	150.
Cbar,	36,	36,	26,	36,	1.
Pbar,	36,	36,	0.01	0.02	0.02	0.03
Mat1,	36,	1.+9,	,	.3 $ massless
Suport,	36,	123456 $ example of bad choice for stiffness criterion
$ optional input for inrel=-3
$ water pressure on outside
$	sid	eid	p1	p2	p3	p4
pload4,	1,	11	-3500.	-3500.	-3500.	-3500. $ bottom
=,	=,	*2,	==
=2
$ payload
grid,	1,	,	50.	0.	50. $ compartment centers
grid,	2,	,	150.	0.	50.
Grid,	3,	,	250.	0.	50.
Grid,	4,	,	350.	0.	50.
Conm2,	1,	1,	,	3.5+6 $ oil in bow tank
Conm2,	2,	2,	,	=
Conm2,	3,	3,	,	=
Conm2,	4,	4,	,	=
Rbe3,	100,	,	1,	123456,	1.0,	123,	11,	12
,	13,	14,	1.0,	12,	21	22	23	24
$ spread load.  top surface has no vertical component
Rbe3,	200,	,	2,	123456,	1.0,	123,	13,	14
,	15,	16,	1.0,	12,	23	24	25	26
Rbe3,	300,	,	3,	123456,	1.0,	123,	15,	16
,	17,	18,	1.0,	12,	25	26	27	28
Rbe3,	400,	,	4,	123456,	1.0,	123,	17,	18
,	19,	20,	1.0,	12,	27	28	29	30
$model centerline point to check solution
grid,	5,	,	200.	0.	50. $ at cg
rbe3,	500,	,	5,	123456,	1.0,	123,	15	16
,	25,	26
grav,	2,	,	10.,	0.,	0.,	-1.
Load,	12,	1.0,	1.0,	1,	1.0, 2 $ required with grav
$ optional data
param, grdpnt,	0 $ find mass, c.g.
param, tiny, 1.e-4 $ suppress small spc forces
enddata

This is a model of a tanker. It is modeled in Elbonian units, where everything is defined in integer numbers, preferably powers of 10.  This allows easier hand calculation of results.