Ship Size, Tonnage and Crew

In most cases “Tonnage” is not exactly weight. Displacement measures weight of a volume of water displaced, not the vessel’s absolute weight in pounds put on a scale. It should not be confused with other measurements of volume. Since we don’t usually have water in space. . . values are slightly different. The Zuku’s from the desert planet of Blarb might have a different measurement.

Merchant ships on the other hand are usually measured based on the volume of cargo they can carry.

One Displacement Ton is roughly the equivalent of 13.5 kiloliters of volume. This can be solid metal OR a wide open area.

Real world the International Space Station is 419,455KG, which in some books is about 419 metric tonnes (or 924,739 pounds). The habitable volume is 388 cubic meters (13,696 cubic feet). Pressurized volume is 916 cubic meters. This equates to about 2.1 cubic meters of livable space per tonne. Overall the ISS is larger than a six bedroom house with 6 crew, or 152 cubic meters per person. Sounds spacious, but it isn’t. The ISS is spread out over the size of a football field.

By comparison a nucleur submarine has a crew of 14 officers, 18 chief petty officers (senior enlisted) and 109 other enlisted men and pretty much everyone works a lot more than 8 hours a day. A ‘day’ onboard a submarine is 18 hours, not 24. This equates to three different six hour shifts, so someone works 6 hours and then is off for 12 hours. One side effect of this is that three crewmen share the same rack.

Now. An Ohio class submarine is 16,764 tonnes surfaced. 18,750 tonnes submerged. The length is 170 meters (560 feet) and about 13 meters tall (42 feet) and about 10.8 meters wide. So using raw numbers that is 23,868 cubic meters, but because of the dimensions (not a perfect box) we will shave off some space and call it 18,000 cubic meters which includes everything from engines to toilet water. If we are generous and say 1/3 of that is actually habitable space (I’ve been on subs and it might actually be a lot less than that), we are down to 6,000 cubic meters of ‘livable’ but very cramped and claustrophobic space. So. . . Playing the numbers game that is about 42 cubic meters per person and about 1 tonne per cubic meter.

International Space Station and an Ohio Submarine Comparison

	ISS	Ohio Sub
Crew	6	142
Tonne (Metric)	419	18750
Length	51	170
Width	109	10.8
Height	73	13
Pressurized Volume	916	6000
Cubic Space Per Person	152	42
Tonnage per Cubic Meter	2.1	1
Tonne per Person	70	132

Below is a list of modern warships. Note that the Zumwalt is one of the most advanced and most automated ships currently produced.

Modern Warships

Ship Class	Tonnage	Crew	Role	TonePerCrew	Length(m)	Beam(m)	Draft(m)
Shchuka	704	38	Submarine (Medium)	19	57	6.2	3.78
Flower	1036	85	Corvette	12	62.5	10.1	3.51
Barracuda	1179	37	Submarine(attack)	32	59.77	7.49	4.39
Whisky	1350	54	Submarine(Coastal Patrol)	25	83.3	6.5	4.9
Dekabrist	1354	53	Submarine (Diesel)	26	76	6.5	3.8
Gleaves	1630	276	Destroyer	6	106.15	11	4.01
K-Class	2600	67	Submarine (Cruiser)	39	97.65	7.4	4.51
Hamilton Class	3250	167	Cutter	19	115	13	4.6
Golf-class	3553	83	Submarine(Ballistic Missile)	43	98.9	8.2	8.5
Anzac	3600	163	Frigate	22	118	14.8	4.35
Kilo-class	3950	52	Submarine(Diesel)	76	74	9.9	6.5
Adelaide	4100	198	Frigate	21	139	14	6.7
Oliver Hazard Perry	4100	235	Frigate	17	138	14	6.7
National Security	4600	113	Cutter	41	127	16	6.9
Virginia	7900	135	Submarine(Attack)	59	115	10	N/a
Arleigh Burke	9800	303	Destroyer	32	155	20	9.3
Ticonderoga	9800	400	Guided Missile Cruiser	25	173	16.8	10.2
Sea Wolf	12139	140	Submarine(Nuclear Attack)	87	108	12	N/A
Zumwalt	14564	140	Modern Destroyer	104	180	24.6	8.4
Minotaur	14800	802	Cruiser	18	158.2	22.7	7.9
Lord Nelson	18106	800	Battleship	23	135.18	24.23	8
Ohio	18750	155	Submarine(Ballistic Missile)	121	170	13	10.8
Invincible	20750	1000	Battle Cruiser	21	173	23.9	9.1
New York	28367	1042	Battleship	27	175	29.03	8.7
Alaska	34253	2251	Heavy Cruiser	15	246.43	28	9.68
Essex	36380	3120	Aircraft Carrier	12	270.7	45	8.4
Typhoon	48000	160	Submarine(Ballistic Missile)	300	175	23	12
Iowa	58000	2250	Fast Battleship	26	270	33	11
Montana	70965	2572	Battleship	28	280	36.93	10.97
Nimitz	94781	5828	Aircraft Carrier	16	332.8	76.8	12.5
TI-Class	517660	20	Super tanker	25883	380	68	24.5
Seawise Giant	646642	40	Super tanker	16166	458.45	68	24.6