what is the Displacement Mass (tonnage) of the Shrike?

House of Steel says 21,000 but that can't be right. Smaller things don't have larger displacements than larger things. The Shrike is smaller than the 282 LAC and that is smaller than the Highlander LAC.

Shrike about 63 x 21 x 20 metres.

282 LAC about 121 x 21 x 22 metres.

Highlander about 138 x 21 x 23 metres.

Ships all use the a similar formula length x width x height x 0.23 x cylinder dimensions not rectangle dimensions, then there is tapering and hammer heads etc... Weight and density only affects the displacement of floating things. It is never more than total displacement. And in space things don't weight anything, they have inertial mass but that is rendered to zero or a set value by wedges and compensator fields.

If we just take roughly a rectangular value of each ship based on rough dimensions. cubic metres.

Highlander is 138 x 21 x 23 = 66654 rectangular cubic metres. Now a Highlander isn't exactly rectangular, but rather more cylindrical, so multiply that by .6666... Then apply the magic 0.23... and you get the listed mass tonnage listed in HoS. One might prefer a M3 (cubic metres) displacement, but that is not the Tons Mass way...

The Shrike is 63 x 21 x 20 metres = 26460 cubic rectangular metres, cylinder calculation takes this to about 17662 protrusions etc and tapering plus and minus... apply the 0.23 magic number and the Shrike is no where near the 21,000 tons mass (displacement). Closer to 4000 tons.

To be 21,000 tons the Shrike would need to be assuming it can't be more than 63 metres long. About 63 x 46 x 47 metres. So if it is about 21,000 tons is it really fat or is it 4,000 - 5,000 tons in Displacement tonnage.

Lord Skimper wrote:House of Steel says 21,000 but that can't be right. Smaller things don't have larger displacements than larger things. The Shrike is smaller than the 282 LAC and that is smaller than the Highlander LAC.

The Highlander is probably rated in displacement, since it is an independent ship in its own right. The 282 and Shrike make more sense to be rated by actual mass since their docking facilities (CLAC or Base) have to deal with their momentum and they are not independent of their docking facilities. 282 and subsequent LACs are essentially appendages of larger weapons systems.

House of Steel is the last word on Ship stats. If it says 21K tons, then it is 21K tons no matter how that might confuse you.

What are the dimensions of a full swimming pool versus an empty swimming pool? Exactly the same. Yet they obviously weight differently.

The Shrikes has a higher density. Some larger starships apparently do have swimming pools, basketball courts and so on aboard them - these are vast, dimension-stretching volumes which mass almost nothing.

I would suspect the main difference is due to the power/fuel source. A Shrike has a compact fission reactor full of heavy metals; old LACs were provided with fusion bunkerage - hydrogen, the lightest of all elements! - for at least a few months' endurance.

munroburton wrote:What are the dimensions of a full swimming pool versus an empty swimming pool? Exactly the same. Yet they obviously weight differently.

The Shrikes has a higher density. Some larger starships apparently do have swimming pools, basketball courts and so on aboard them - these are vast, dimension-stretching volumes which mass almost nothing.

I would suspect the main difference is due to the power/fuel source. A Shrike has a compact fission reactor full of heavy metals; old LACs were provided with fusion bunkerage - hydrogen, the lightest of all elements! - for at least a few months' endurance.

Also a telling difference between Shrikes (and other modern LACs) and older LACs and Starships is their msintenance patterns. Shrikes are designed for depot mainenance- they are maintained from the outside of the craft in a LAC bay. Starships are designed for self msintenance, with corridors and access ways to allow wirkers to maintain all the aspects of a ship from the inside.

Thus means that more of a shrike is filled with hardware, while more of a Starship is corridor or accessway, making the Shrike more dense.

Nothibg in House of Steel says the tonnages listed are displacement tonnages. We happen to know in the great resizing that the density was used to set the sizes; which just means almost all warships have similar density. It doesn't necessarily mean that the tonnage is displacement tonnage just because it tracks closely with volume. So in HoS the Shrikes are higher density - that doesn't mean their tonnage is a different type than larger warships.

So basically Skimper seems to be working from an unsubstantiated assumption.

Jonathan_S wrote:So basically Skimper seems to be working from an unsubstantiated assumption.

Which is how he seems to work for virtually everything he ever posts, so this is simply business as usual.

munroburton wrote:What are the dimensions of a full swimming pool versus an empty swimming pool? Exactly the same. Yet they obviously weight differently.

The Shrikes has a higher density. Some larger starships apparently do have swimming pools, basketball courts and so on aboard them - these are vast, dimension-stretching volumes which mass almost nothing.

I would suspect the main difference is due to the power/fuel source. A Shrike has a compact fission reactor full of heavy metals; old LACs were provided with fusion bunkerage - hydrogen, the lightest of all elements! - for at least a few months' endurance.

You're confusing the endurance of RMN battlecruisers with that of light attack craft:

Echoes of Honor, Chapter 3 wrote:Gearman pursed his lips in a silent whistle at that. One of a conventional LAC's several drawbacks was that its small size prevented it from cramming in anything like the bunkerage of regular warships. RMN battlecruisers could take on sufficient reactor mass for almost four months, but they were specifically designed for long-range, deep penetration raids as well as convoy protection. A light attack craft, on the other hand, was fortunate to be able to stow sufficient hydrogen for a three-week deployment, which made her dreadfully short-legged compared to her betters. But if she only had to refuel every eighteen years—!

Boldface is my emphasis.

Jonathan_S wrote:Nothibg in House of Steel says the tonnages listed are displacement tonnages. We happen to know in the great resizing that the density was used to set the sizes; which just means almost all warships have similar density. It doesn't necessarily mean that the tonnage is displacement tonnage just because it tracks closely with volume. So in HoS the Shrikes are higher density - that doesn't mean their tonnage is a different type than larger warships.

So basically Skimper seems to be working from an unsubstantiated assumption.

Really but things in space don't weigh anything.

Lord Skimper wrote:Really but things in space don't weigh anything.

They still have mass.

Weird Harold wrote:

Lord Skimper wrote:Really but things in space don't weigh anything.

They still have mass.

Right, kilograms are a measurement of mass, while pounds are a measurement of weight. Weight is defined as mass measured in a gravitational field.

So on Sphinx, a kilogram of a substance will weigh 1.35 times as much as it would on Earth, but it still masses 1 kilogram. In freefall in space, ot would weight nothing, but still have the mass of 1 kilogram.