Imperial Navy numbers

[rancke]

We've discussed Naval Depots a lot lately. One thing that's come up is the number of people stationed in a depot. To provide a bit of perspective, I'm going to post the numbers for the navy that I've worked out.

These numbers are based on various canonical passages that may not be accepted and various assumptions that may not be accepted either. So I've briefly indicated the basic premises I've used to come up with my figures. You must judge for yourself how plausible they are.

The Imperial Navy has around an average of 63 combat vessels (aka large combattants) per regular fleet. (Interpreting Rebellion Sourcebook's 1000 combat vessels per sector as 1000 per 16 subsectors).

Large combattants are organized in squadrons of 8 indentical ships and an unspecified number of auxiliaries. For a variety of reasons some squadrons have only 6 or 4 main ships; the actual average is 7 ships per squadron (note: squadrons with odd numbers of main ships are rare).

Squadrons are either cruiser squadrons (CruRons) with medium large ships or battleship squadrons (BatRons) with large ships. Specialist squadrons (e.g. TankRons, AssaultRons) are auxiliaries.

The average crew on battleships is 2,250 (average of the three battleships in FS).

The average crew on cruisers is 455 (average of the eight cruisers and carriers in FS).

The average squadron has +10% crew serving on auxiliaries assigned to the squadron (Pure guess).

The average BatRon has 7 * 2250 * 1.1 = 17,325 crew.

The average CruRon has 7 * 455 * 1.1 = 3,500 crew. (Rounded off from 3,503.5)

The mix of BatRons to CruRons is 1:2 (FFW countermix).

The average fleet has 3 BatRons and 6 CruRons.

The average fleet has +10% serving on auxiliaries not attached to specific squadrons. (Pure guess).

The average fleet has (3 * 17,325 + 6 * 3,500) * 1.1 = 80,000 crew. (Rounded off from 80,272.5).

The navy has 3 groundbased people for each crew position. (I got that from real life, but I can't remember where -- it was many years ago).

The navy's composition is roughly analogous to that of the USN. (Since that's the only navy I have useful numbers for).

The average fleet has 320,000 employees. (By coincidence (and it is a coincidence... I found this out after I'd done the sums first) this is almost exactly the number of active duty personnel in the USN).

Sum total of the entire IN guestimated to be 102,400,000 active duty personnel.

(Note: Reserve personnel not accounted for).​

Make of that what you want.


Hans

 

[Drakon]

This looks good, but I question the ground personel for the fleet.

If you are talking civilian dependents, then I would buy the 3 to 1 ratio, but even then that seems high.

Ground bases would have separate personel budgets than the fleet. Their function is different. The fleet's headquarter personel would be limited to logistic support, pay and records, communication, and possibly command staff. Admin, repair and supplies are functions that any naval base will require for their own needs and provide to any units that pop in. (Obviously, within reason.) I don't see the fleets themselves have much of a shore presence.

UNLESS:

In the US Navy, the ballistic missile submarines have two crews. Each crew takes the boat for 105 days, first doing a 21 to 28 day refit, fixing up all the stuff the other crew broke, and then take the boat out for a deterrence patrol.

The advantage is that the boat stays out at sea longer, without the crew becoming dangerously crazy. If you had ships that were to spend a long time away from port, then you would need a larger shore presence, to house the second crews.

Most vessels have one crew, and pull into port more frequently. Fast attack submarines do not have split crews. It is unique to FBM boats because of their unique mission, be invisible and ready to nuke the planet at a moment's notice.

(This is incorrect. As my first captain once said. "Our mission is not to launch missiles. Our mission is to stop the other guy from launching his missiles." )

While I do not believe the Imperium has any ships with a similar mission, outside of this, I don't see fleets having that large a shore presence. The ground base personel would need to be figured differently.

80,000 crew for 63 combat ships plus auxiliaries sounds ballpark.

 

[Matt123]

Can you add sources for the first three assumptions. I'm sure you have them

And the statement [FONT=arial,helvetica]"The average fleet has 3 BatRons and 6 CruRons."

The rest is very clear on sources or assumptions, ta.

My gut feel is that you are a bit light on auxiliaries, but I'd have to crunch some numbers before engaging in that debate. Otherwise, very useful stuff. Thanks.

Cheers


[/FONT]

 

[aramis]

Drakon:
The USN has been (recently) switching more and more to split crews for non-subs. They were using dual crews on some Arleigh Burke and Spruance class destroyers in 2002 - 2006 as a field test, and as standard for LCS, MCS, and PC ships.

Not all are 2-crew, either. 13 crews for 8 ships in the case of the Cyclone class PCs.

The use of multiple crews allows for the ship to remain on station longer when the crew needs down-time, and also allows running to full crew endurance on station. (The ship's endurance when using underway replenishment has exceeded crew endurance since the mid 60's, if not longer.)

I have seen more recent evidence (but am too lazy to check for current) of a of a Burke with dual crews.

----

http://www.cbo.gov/sites/default/files/cbofiles/ftpdocs/87xx/doc8771/10-31-navy.pdf

 

[Condottiere]

1. Since insurance premiums are less of an issue with the military, the auxiliaries and ground personnel may be more heavily automated than the combat vessels.

2. Speaking of which, they might have a third shift who are frozen popsicles.

3. Some smart spark in the Admiralty may decide that one or two classes of patrol vessels can be configured to be undermanned, and personnel can be surged in the event of conflict.

 

[aramis]

3. Some smart spark in the Admiralty may decide that one or two classes of patrol vessels can be configured to be undermanned, and personnel can be surged in the event of conflict.

It's more likely that the line vessels would be short shifted. Not the flagships, mind, but in the BB-CA-CL-DD-E-T/P sequence in canon it's likely the CA's, CL's, and DD's that get shorted; the BB's don't because the Admirals are aboard them, plus they go "show the flag" with their onboard battalion of marines. The T/P can't operate short shifted without seriously experienced crews. The heavier escorts (500-1200 Td) start having some duplication of crew that allows for shorting, but when shorted, a man sick/injured/insane is a ship stopped.

It's not until you get to the big suckers that you have sufficiently large crews to short them without people pulling doubles.

Then again, it's also quite practical to short gun crews in peace time by seconding them to other departments.

 

[rancke]

This looks good, but I question the ground personel for the fleet.

If you are talking civilian dependents, then I would buy the 3 to 1 ratio, but even then that seems high.

No, I'm talking support, administration, training.

Have a look at the USN for comparison. It has 10 aircraft carriers with a crew of 5,680 each for a total of 56,800. I don't have the patience to hunt down the crew numbers for the rest of its 9 amphibious assault ships, 10 amphibious transport docks, 12 dock landing ships, 22 cruisers, 62 destroyers, 17 frigates, 3 littoral combat ships, and 71 submarines, but I think that another 25,000 crew slots sounds pretty plausible (feel free to refine those figures if you like). That would make the number of crew slots roughly 80,000 out of a toral of 323,951 active duty personnel.

Dependents would be extra.


Hans

 

[rancke]

It's more likely that the line vessels would be short shifted. Not the flagships, mind, but in the BB-CA-CL-DD-E-T/P sequence in canon it's likely the CA's, CL's, and DD's that get shorted; the BB's don't because the Admirals are aboard them, plus they go "show the flag" with their onboard battalion of marines. The T/P can't operate short shifted without seriously experienced crews. The heavier escorts (500-1200 Td) start having some duplication of crew that allows for shorting, but when shorted, a man sick/injured/insane is a ship stopped.

The five escorts featured in FS have an average crew of 23. I'm sure the IN has lots and lots of escorts, but I don't think doubling the crews on them will affect the total crew numbers significantly.


Hans

 

[aramis]

The five escorts featured in FS have an average crew of 23. I'm sure the IN has lots and lots of escorts, but I don't think doubling the crews on them will affect the total crew numbers significantly.


Hans

The biggest problem with multi-crewing in Traveller is that of getting crews to/from the deployment.

For a system fleet, it's a non-issue.

For the fleet of a subsector which remains within its subsector, it's a non-issue as well - swap crews every time it rotates through homeport.

If, however, you have a fleet that's more than a few jumps from homeport, finding them may be the problem.

It may be easiest to send the replacement crew to the fleet forward ops center (which would be known to homeport HQ, usually), and wait for it to finish deployment patrol circuit. Which may or may not mean forward ops has all the "off" crews... for lack of ability to send them home and back in time.

Likewise, a deployment to another sector makes the home port practically irrelevant - the supply chain is too slow given the needs.

 

[rancke]

It's quite possible that I'm underestimating the 'logistics fleet', to coin a term -- the transports that haul supplies, ammunition and personnel around.


Hans

 

[tjoneslo]

We've discussed Naval Depots a lot lately. One thing that's come up is the number of people stationed in a depot. To provide a bit of perspective, I'm going to post the numbers for the navy that I've worked out.

These numbers are based on various canonical passages that may not be accepted and various assumptions that may not be accepted either. So I've briefly indicated the basic premises I've used to come up with my figures. You must judge for yourself how plausible they are.

Make of that what you want.

I'm going to refer you to an older analysis by Chris Thrash regarding the number of "Travellers": http://www.prismnet.com/~thrash/travpop.html

 

[rancke]

I'm going to refer you to an older analysis by Chris Thrash regarding the number of "Travellers": http://www.prismnet.com/~thrash/travpop.html

Chris' estimate of 1 crewman per 20T of combattant is far too high. The average for the cruisers and battleships in FS is 1 crew per 132T. His estimate of 7.1-31 million total tonnage for the IN is high too (although his lower bound is less than the figure I get (8.8 million tons)).


Hans