Acceleration and maneuvering in space

This thread is continued in and closely related to:

>From: Onno Meyer <Onno.Meyer@arbi.informatik.uni-oldenburg.de>
>Subject: cherryhlist
>Date: Mon, 17 May 1993 16:17:19 +0200 (MET DST)

(...)

Next question: How does a carrier reach these velocities? At the end of _DS_, _Norway_ accelerates to a significant percentage of light- speed, decelerates, turns around and comes back at high speed without crushing the crew or using jumpdrive?

	Onno

view full message

>From: Jo Jaquinta <jaymin@maths.tcd.ie>
>Subject: cherryhlist: acceleration
>Date: Tue, 18 May 93 16:54:41 BST

Onno writes:
>Next question: (...)

Yes. She states somewhere in _DS_ that a carrier can hit up to 10G, with the synced rotational crew-cylinder. If you do the calculations though, the Norway breaks dock at Pell at XX:00, and at YY:00 it is going .75C. Plugging the numbers into your standard newtonain acceleration you get the Norway accelereating at 43G!
This bugged me for some time. My theory was that the jump vanes provided some sort of inertial compensation. (If you've got one magic device, might as well make it explain everything) I.e. if slightly charging the vanes dampened things by a factor of 10 then real-world acceleration of 43G computes to a perceived acceleration of 4.3G.
However, in the end of Chanur's Legacy, (somewhere) she talks about "boosting up". Like when you cycle the vanes to dump velocity, here she cycled the vanes to increase velocity.
This would give the ship the high momentumn, more or less instantaneously, but cuts out maneuvering. I would imagine it is a high-power maneuver that really only military-spec powerplants could hit reliably. (Or unloaded merchants...)
I can see a wonderful fleet maneuver when the are zooming across the system, dump down to nil, make a right angled turn, and boost back up again. Kind of thing Union would never expect...

Jo

view full message

>From: Lesley Grant <lgrant@maths.tcd.ie>
>Subject: cherryhlist
>Date: Wed, 19 May 93 9:59:43 BST

Jo writes:
> 	I can see a wonderful fleet maneuver when the are zooming across
> the system, dump down to nil, make a right angled turn, and boost back
> up again.  Kind of thing Union would never expect...

Sounds like the Knnn to me. Doesn't Pyanfar speculate at one point what that sort of maneuver would do to the average Compact oxy-breather's body? eeew :-(

(...)

				Lesley

view full message

>From: Onno Meyer <Onno.Meyer@arbi.informatik.uni-oldenburg.de>
>Subject: cherryhlist
>Date: Fri, 21 May 1993 10:38:29 +0200 (MET DST)

(...)

> 	Yes. She states somewhere in _DS_ that a carrier can hit up
> to 10G, with the synced rotational crew-cylinder. If you do the calculations
> though, the Norway breaks dock at Pell at XX:00, and at YY:00 it is
> going .75C. Plugging the numbers into your standard newtonain acceleration
> you get the Norway accelereating at 43G!

But todays rockets spent a huge percentage of their mass to operate for shorter periods of time with less acceleration. What kind of exhaust velocity would be required for the carriers?

[...]
> 	However, in the end of Chanur's Legacy, (somewhere) she talks
> about "boosting up". Like when you cycle the vanes to dump velocity,
> here she cycled the vanes to increase velocity.
> 	This would give the ship the high momentumn, more or less
> instantaneously, but cuts out maneuvering. I would imagine it is a
> high-power maneuver that really only military-spec powerplants could
> hit reliably. (Or unloaded merchants...)
[...]

But in _Merchanters Luck_, the trampfreighter was empty and still slow. (Okay, it was an obsolete ship in bad shape, but it was a jumpship.)

Onno

(...)

view full message

>From: Onno Meyer <Onno.Meyer@arbi.informatik.uni-oldenburg.de>
>Subject: cherryhlist
>Date: Mon, 24 May 1993 07:54:55 +0200 (MET DST)

> 	This bugged me for some time. My theory was that the jump vanes
> provided some sort of inertial compensation. (...)
> 	However, in the end of Chanur's Legacy, (somewhere) she talks
> about "boosting up". Like when you cycle the vanes to dump velocity,
> here she cycled the vanes to increase velocity.
> 	This would give the ship the high momentumn, more or less
> instantaneously, but cuts out maneuvering. (...)
> 	I can see a wonderful fleet maneuver when the are zooming across
> the system, dump down to nil, make a right angled turn, and boost back
> up again.  Kind of thing Union would never expect...
> (...)

If this is correct, why are there riderships at all? I allways assumed riders would have advantages in realspace combat because they saved the mass of the FTL-drive. We know there are small combat jumpships (dartships?). These craft should be capable of all ridership maneuvers, and with the possibilities of "boosting up" and independent missions they would be much more powerfull.
Do I miss some advantage of the ridrships?

(...)

Onno

view full message

>From: Onno Meyer <Onno.Meyer@arbi.informatik.uni-oldenburg.de>
>Subject: cherryhlist
>Date: Fri, 28 May 1993 17:18:52 +0200 (MET DST)

(...)

> (...)
> 	Basically if the dump-turn-boost maneuver is possible for
> a carrier it would have to be a special maneuver, when the enemy is
> completely off guard. Whereas riders do it all the time.
> I also get the impression that dipping in and out of jump-space is 
> very noticable.

I'm not sure we're talking about the same things here :-) When I say "dump-turn-boost", I think of a speed dump by partially entering the interface(?), a turn with realspace engines, and a boost with the FTL-engines.
A ship capable of doing this needs FTL-engines. If a ridership (without a FTL-engine) dumps speed or boosts up it has to do it with realspace engines, using reaction mass and subjecting the crew to acceleration.

A carrier may "shed its riders, which will travel at that speed". I read from this that a ridership is not capable of the major speed/vector changes done with the FTL-engines. Of course, this interpretation is not supported by the remainder of the text (the notes about rider movement).

One more point, how old is this text? The information on rider crew numbers contradicts the information in _HB_, and I think _HB_ is one if the newer books. ['the text' referred to is an essay by C.J. Cherryh written as part of the 'Company Wars' boardgame. See The 'Company War' boardgame and essay - AW]

            Onno