Compensator Field/Impeller

Finally found the quote we have been looking for.

Compensator Field Density: Bolding mine:
http://weber.fit2.bur.st/www/20041218_HH_11_ship_strengths_update.html

"As I’ve said before, the acceleration rate possible for a ship is related to both mass and volume. When the vessel is built, its impellers AND compensator are designed around its mass and the volume of space which must be enclosed within the compensator’s field. The maximum efficiency of the components is set at that time, which is why simply reducing mass doesn’t necessarily increase acceleration. The volume of the field, combined with the efficiency and power of the compensator and the maximum depth of “sump” which can be generated using its impellers, have all been factored in when the ship’s original maximum acceleration is determined."

Short of it is: Density varies. As is obvious from anyone who calculates the smaller classes from dims given in HoS compared to the Battlecruisers and SD's. Otherwise said field cannot be related to both mass and volume as variables in your design concerning acceleration and impeller strength required.

It is NOT fixed as many have postulated at the 0.25 that was attributed to the great resizing. Yes, 0.25tons/m^3 is a good place to start. So, the Caravan class AMC roughly works to the 0.25 number, but the quote above clearly demonstrates that other Freighters could easily be working to a much lower density for their cargo hold. Therefore some freighters could be larger if their design calls for them to carry less dense cargos on average. For instance common cargo density here on earth is roughly 0.17. Can be as low as 0.08 and as high as 0.3 I believe.

wastedfly wrote: For instance common cargo density here on earth is roughly 0.17. Can be as low as 0.08 and as high as 0.3 I believe.

I suspect that iron ore is just a little bit more dense than that. And most cargo sinks, which tends to suggest a density greater then 1 ton per cubic meter.

kzt wrote:

wastedfly wrote: For instance common cargo density here on earth is roughly 0.17. Can be as low as 0.08 and as high as 0.3 I believe.

I suspect that iron ore is just a little bit more dense than that. And most cargo sinks, which tends to suggest a density greater then 1 ton per cubic meter.

He misspoke. He's actually talking about the overall density of a laden ship, not the density of the cargo itself. Since the ship floats, the overall density is clearly less than 1.

We already knew that the actual Honorverse ship density is not exactly 0.25. Only a few people argued otherwise. That is why I have always been careful to distinguish the designated "ship mass" from the actual mass of a ship. However, as Wastedfly points out, the "ship mass" is a reasonable guess for the actual mass, in the absence of other information. In fact, that's what David himself said, when discussing what the value should be for the Great Resizing.

kzt wrote:

wastedfly wrote: For instance common cargo density here on earth is roughly 0.17. Can be as low as 0.08 and as high as 0.3 I believe.

I suspect that iron ore is just a little bit more dense than that. And most cargo sinks, which tends to suggest a density greater then 1 ton per cubic meter.

Bulk/ore ships, are not defined as a cargo ship here on earth. So, no, I did not misspoke. They are their own separate category for passage through the Suez/Panama canal zones. For these ships, I believe their cost is due to empty displacement combined with total amount of ore, wheat, lumber, oil, etc. Depends on the type of bulk ship as well.

Most cargo does not sink. That would be a very rare exception. Most TEU's are full of air/foam/wood/plastic. There is a reason TEU's fallen off of container ships are a major shipping hazzard. Yes, they eventually let enough water in, displacing the air present allowing the TEU to sink. Why? Because the TEU tare weight itself is a large portion of the allowed tonnage per TEU. You can get special TEU's shipped with far higher tonnages. Costs more.

So is an empty freighter faster or slower or the same speed as that same freighter carrying SD armour? Would a vacuum filled freighter, which is totally empty, move faster?

How does the mass affect the compensator in a micro gravity state? Is it an inertia thing?

Could a freighter lower the compensator field dimensions to go faster? Compromise some cargo but escape the pirate!

If you could eject cargo to change the parameters and possibly increase your speed to outrun a pirate, they we would mostl likely see Q-ships playing sucker in the pirate.

You might start "dumping" cargo to change your displacement and speed relative to your compensators…. and just happen to have a few missile pods dressed as cargo containers which are what is being dumped. Say 8 warshots missiles per container plus an EW bird, drop 3 containers and your pirate -or your average DD or CL commerce raider- is going to have a really bad day when they are screaming down on the fleeing "merchant" and 24 hot weapons blow out of their pods and are comming down the raider's throat.

I suspect that it is relativly difficult for merchant ships to just "dump" cargo while in flight. I don't recall seeing that done in the series. I also don't think that you could get enough improved performance out of a merchant ship by dumping a couple of hundred thousand tons of cargo to outrun much of anything on a 4million ton cargo ship- or even a 2million ton ship.
Just opening the doors on cargo holds isn't going to do the job. You are going to have to actually move the cargo (hopefully containerized) from how it is stored to where it can get physically ejected through the open hatch. That is, as they say, "going to take a while". You would be leaving a trail of stuff and your performance improvement is going to be in very small increments as stuff leaves the fields of the ship.

Blowing the cargo out of one or more holds is going to risk some significant damage to the ship even if there was some mechanism to unsecure the load and use explosive decompression to throw the cargo out. Then there is the question about what kind of problems your engineering staff is going to have to deal with between the rapid changes of forces and shifting balance on things like the drive and compensators/inertial dampers.

This comes under the heading of a really BAD IDEA.

Lord Skimper wrote:So is an empty freighter faster or slower or the same speed as that same freighter carrying SD armour? Would a vacuum filled freighter, which is totally empty, move faster?

How does the mass affect the compensator in a micro gravity state? Is it an inertia thing?

Could a freighter lower the compensator field dimensions to go faster? Compromise some cargo but escape the pirate!

Quoting from the extract in the original post:

"The maximum efficiency of the components is set at that time, which is why simply reducing mass doesn’t necessarily increase acceleration. The volume of the field, combined with the efficiency and power of the compensator and the maximum depth of “sump” which can be generated using its impellers, have all been factored in when the ship’s original maximum acceleration is determined."