LAC vs. Destroyer and Cruiser accelerations.

So… I was re-reading house of steel last night and I found something that blew my mind.
The maximum acceleration of a Shrike, Ferret, or Katana LAC is just over 600 gravities. However, the max acceleration of a Roland-class DD is nearly 800 gravities. What's more, the Nike-class BC has a maximum acceleration of more than 600 gravities as well. Yet everything I've read in the other books indicates that LACs have higher accelerations than just about any hyper-capable warship. Can someone please explain this?

HoS' acceleration specs are(with a few exceptions) for the year that design entered commission. So in 1917, Katanas were doing 640g in 1917 and the Nike/Roland arrived in 1920 with 674/780g.

You can see this more clearly in the SD(P) section, where a 1914 Medusa pulls 502g and a 1919 Invictus pulls 560g. And the Harrington-II doing 561g, also in 1919. About a 12% increase, although they did add some more mass.

munroburton wrote:HoS' acceleration specs are(with a few exceptions) for the year that design entered commission. So in 1917, Katanas were doing 640g in 1917 and the Nike/Roland arrived in 1920 with 674/780g.

You can see this more clearly in the SD(P) section, where a 1914 Medusa pulls 502g and a 1919 Invictus pulls 560g. And the Harrington-II doing 561g, also in 1919. About a 12% increase, although they did add some more mass.

So the later models of Shrikes and Ferrets would have better acceleration?

bensellers wrote:So the later models of Shrikes and Ferrets would have better acceleration?

Yes. They can probably all pull over 800g at max power.

I wonder if we'll see any manned vessel break 1000g before the series end.

munroburton wrote:

bensellers wrote:So the later models of Shrikes and Ferrets would have better acceleration?

Yes. They can probably all pull over 800g at max power.

I wonder if we'll see any manned vessel break 1000g before the series end.

You're right - We're currently seeing new Manticoran construction (like the Hexapuma) pulling ~145% 1905 acceleration levels. The same % on a LAC (which in 1905 would have pulled ~550 Gs max if a LAC could use it's full compensated power) would be just a hair shy of 800 Gs at max power.

From what David said about only 2 books left in this series - I don't forsee another 35% improvement in the next 1-3 of story time.

Given the possibility of the series jumping 20 years or so and starting with Honor's kids, it is quite possible that we could see improvements that allow 1000 Gs or more in a warship'd acceleration.

While this topic was up near the top, I wanted to remind all about several other observations about House of Steel.

1) As mentioned above, Accel is noted as design or initial unit accel - not what is currently fielded, or fielded by the majority of the class.

2) Weapons fit is as of last major refit for the class. It is not the original weapons fit, nor is it what every member of the class actually has.

3) Build #s are RMN acceptance numbers. They are not what was laid down, or even completed, but only what the RMN accepted into service. ~30 RMN spec ships were sold directly to the GSN and are not accounted in the RMN class build numbers, as are other ships built directly for other navies or never completed, or ships lost prior to completion, as in Grendlesbane.

4) The time chop for this book is May 1st 1921. Any ship completed and accepted into the RMN or GSN after this date is not included in the represented build numbers. It specifically does not represent the final count - or even surviving count - from Oyster Bay ~10 months later.

5) The classes mentioned in the book are classes active in the RMN post 1900pd. Any class (not ship - class) which retired prior to 1900 pd is not mentioned except in reference to another, current class.

An mentioned, this book is supposedly collected information from Civilian sources, so may be wrong - either accidentially, or intentionally, to suit the story line and any changes David may make.

Theemile wrote:You're right - We're currently seeing new Manticoran construction (like the Hexapuma) pulling ~145% 1905 acceleration levels. The same % on a LAC (which in 1905 would have pulled ~550 Gs max if a LAC could use it's full compensated power) would be just a hair shy of 800 Gs at max power.

The Wolfhound and Roland class DDs, even from their HoS numbers, appear to pull 151.51% of 1905 acceleration levels (or as I tend to call them pre-Grayson acceleration levels).

And if you go to the books in SftS we saw a formation including Invictus-class SD(P)s make a max acceleration run at 6.1 KPS^2; which would be 153.93% of their 1905 numbers, and is still 108.43% of their initial unit acceleration numbers (from HoS)


So if that same 153.93% improvement applies to a Shrike it could conceivably pull 834.7g flat out, or 751.28g at the new max safe level of 90% power!

[And yes, I do have a spreadsheet with every solid ship acceleration number I've found, from Jayne's, SITS, HoS, and some from the books.
From which I derived accel curves for 1905-era ships by tonnage; far more nuanced than the accel table in MtH]

Jonathan_S wrote:

Theemile wrote:You're right - We're currently seeing new Manticoran construction (like the Hexapuma) pulling ~145% 1905 acceleration levels. The same % on a LAC (which in 1905 would have pulled ~550 Gs max if a LAC could use it's full compensated power) would be just a hair shy of 800 Gs at max power.

The Wolfhound and Roland class DDs, even from their HoS numbers, appear to pull 151.51% of 1905 acceleration levels (or as I tend to call them pre-Grayson acceleration levels).

And if you go to the books in SftS we saw a formation including Invictus-class SD(P)s make a max acceleration run at 6.1 KPS^2; which would be 153.93% of their 1905 numbers, and is still 108.43% of their initial unit acceleration numbers (from HoS)


So if that same 153.93% improvement applies to a Shrike it could conceivably pull 834.7g flat out, or 751.28g at the new max safe level of 90% power!

[And yes, I do have a spreadsheet with every solid ship acceleration number I've found, from Jayne's, SITS, HoS, and some from the books.
From which I derived accel curves for 1905-era ships by tonnage; far more nuanced than the accel table in MtH]

It occurs to me that the newest all-up warships could have incorporated beta-squared nodes. Would this have improved their max accel, perhaps even closing the gap on the new LACs?

munroburton wrote:]It occurs to me that the newest all-up warships could have incorporated beta-squared nodes. Would this have improved their max accel, perhaps even closing the gap on the new LACs?

Pretty much any hyper capable warship has more wedge power than it can use. In them max accel is limited by the compensator, not the wedge.
That said I believe the books be mentioned that the Saganami cruisers already incorporated Beta Squared nodes; it was described, along with their bow wall, when Mike (IIRC) got command of one.

So way before the Sag-C, or newer types. That saved some mass/volume but as far as I know didn't, in and of itself, improve their acceleration.

munroburton wrote:It occurs to me that the newest all-up warships could have incorporated beta-squared nodes. Would this have improved their max accel, perhaps even closing the gap on the new LACs?

Max accel for almost all ships isn't set by nodes, it's set by the efficiency of the compensator, and it's the improvements in that piece of tech that have led to the increases in accel over the series.

The beta-squared nodes basically just let you generate a more powerful wedge with less mass invested in nodes. That's nice, but for normal warships that won't increase acceleration. The Shrike actually did get an acceleration increase from the beta-squared nodes, but that's because previous LACs didn't actually have powerful enough wedges to even max out their inertial compensators. (One example is the Grayson LACs being slower than their other ships in HotQ.) The same isn't true for regular warships.