The Trek BBS

The Trek BBS (http://www.trekbbs.com/index.php)
-   Trek Tech (http://www.trekbbs.com/forumdisplay.php?f=14)
-   -   How do Starships stop? (http://www.trekbbs.com/showthread.php?t=73159)

Albertus November 9 2008 05:49 AM

How do Starships stop?
 
This is one thing about Trek Tech that has always puzzled me. How do starships stop?

We know from the on-screen commands and actions that a ship at warp speed can translate to a sublight velocity within a few seconds. It is the slowing down from near light speed to a zero velocity that poses the problem.

The impulse engines all point in the wrong direction to be used for a retro-jet action and the Saucer and Battle section thrusters are used for station-keeping and fine maneuvering/attitude control of the ship.

I know that this aspect of Trek ships was considered and the idea of 'reverse thrusters' was mooted but the solution never went further than that throw-away idea and there is nothing in the Tech manual or elsewhere to suggest a method..

So, how does a Trek ship stop?

I have my own solution, but I am interested to hear other peoples ideas.

:techman:

GodThingFormerly November 9 2008 05:58 AM

Re: How do Starships stop?
 
Quote:

Albertus wrote: (Post 2272145)
The impulse engines all point in the wrong direction to be used for a retro-jet action...

...unless one employs forcefield-based thrust deflectors to channel impulse exhaust along the space vehicle's flight vector.

TGT

Albertus November 9 2008 06:11 AM

Re: How do Starships stop?
 
Quote:

The God Thing wrote: (Post 2272169)
...unless one employs forcefield-based thrust deflectors to channel impulse exhaust along the space vehicle's flight vector.TGT

I get the idea, like baffles to reflect the energy backwards? I am not a fan of this idea. This approach would use far more energy than the actual energy needed to slow the ship down. :)

:techman:

Manticore November 9 2008 06:43 AM

Re: How do Starships stop?
 
Quote:

The God Thing wrote: (Post 2272169)
Quote:

Albertus wrote: (Post 2272145)
The impulse engines all point in the wrong direction to be used for a retro-jet action...

...unless one employs forcefield-based thrust deflectors to channel impulse exhaust along the space vehicle's flight vector.

TGT

I personally believe that the impulse engine is primarily a field drive, with only a limited thrust component, so slowing down would be fairly easy.

As for the warp drive, the ship isn't really going so fast. I don't know if it's related to the Alcubierre warp drive concept or not, but slowing down shouldn't be an issue, because the ship isn't really decelerating, just not warping space as much.

GodThingFormerly November 9 2008 06:54 AM

Re: How do Starships stop?
 
Quote:

Albertus wrote: (Post 2272209)
I get the idea, like baffles to reflect the energy backwards? I am not a fan of this idea. This approach would use far more energy than the actual energy needed to slow the ship down. :)

:techman:

I may be inclined to take your objection semi-seriously if you can quantify "far more energy".

Quote:

Manticore wrote: (Post 2272303)
I personally believe that the impulse engine is primarily a field drive, with only a limited thrust component, so slowing down would be fairly easy.

I prefer to interpret TOS/TAS/TMP-era impulse engines as Newtonian rockets, whether they be thermonuclear fusion energized aboard the original NCC-1701 (see The Doomsday Machine) or anti-matter energized aboard the NCC-1701 Refit (see ST:TMP).

TGT

Gep Malakai November 9 2008 08:57 AM

Re: How do Starships stop?
 
Quote:

The God Thing wrote: (Post 2272169)
Quote:

Albertus wrote: (Post 2272145)
The impulse engines all point in the wrong direction to be used for a retro-jet action...

...unless one employs forcefield-based thrust deflectors to channel impulse exhaust along the space vehicle's flight vector.

TGT

...wouldn't it be simpler to flip the ship 180 along the flight path?

GodThingFormerly November 9 2008 09:11 AM

Re: How do Starships stop?
 
Quote:

Gep Malakai wrote: (Post 2272539)
...wouldn't it be simpler to flip the ship 180 along the flight path?

Sure, if the thrust reversers fail. :D But seriously, please feel free to cite an episode or film where we see a standard spacecraft braking maneuver executed via 180 rotation.

TGT

Gep Malakai November 9 2008 09:50 AM

Re: How do Starships stop?
 
Quote:

The God Thing wrote: (Post 2272573)
But seriously, please feel free to cite an episode or film where we see a standard spacecraft braking maneuver executed via 180 rotation.

TGT

Unfortunately, I cannot, as film and TV science fiction is filled with stupid. :D

USS KG5 November 9 2008 11:33 AM

Re: How do Starships stop?
 
Quote:

The God Thing wrote: (Post 2272573)
Quote:

Gep Malakai wrote: (Post 2272539)
...wouldn't it be simpler to flip the ship 180 along the flight path?

Sure, if the thrust reversers fail. :D But seriously, please feel free to cite an episode or film where we see a standard spacecraft braking maneuver executed via 180 rotation.

TGT

They do it in an episode of TNG actually - though I forget which one.

Christopher November 9 2008 03:39 PM

Re: How do Starships stop?
 
According to the TNG Tech Manual, impulse engines reduce the inertial mass of a starship to make it easier to accelerate. Since momentum equals mass times velocity, and momentum is conserved, then simply reducing a ship's effective mass would automatically cause it to go faster, and conversely, increasing its effective mass would cause it to slow down. So all a starship has to do in order to decelerate is to dial back the mass-reduction effect of its impulse-drive field. Conversely, though, if the mass is reduced as much as possible, then that makes it easier to accelerate or decelerate with thrusters (assuming that the thrusters' reaction mass is not itself subjected to mass reduction).

And of course no starship ever "stops," it just matches velocity with some other object in space or goes into orbit of some other body. How much deceleration or course change is needed would depend on what the ship's velocity is relative to its destination or to the other vessel it's rendezvousing with.

Forbin November 9 2008 03:58 PM

Re: How do Starships stop?
 
Perhaps the warp engines are caused to impart a momentary reverse-pulse of the warp field when the captain calls for "all stop." First cutting the ship out of warp, then pulsing to cancel the forward momentum. Once the momentum is below a certain threshold, the thrusters are able to handle the rest

Christopher November 9 2008 06:01 PM

Re: How do Starships stop?
 
^^That's not how a warp drive works, though. It doesn't impart any actual velocity, it just distorts spacetime so that a pocket of it moves forward FTL with the ship being carried along inside it. So a warp drive would have no effect on a ship's momentum.

Albertus November 9 2008 07:20 PM

Re: How do Starships stop?
 
Quote:

Christopher wrote: (Post 2272860)
According to the TNG Tech Manual, impulse engines reduce the inertial mass of a starship to make it easier to accelerate.......

The impulse engines utilise a small space-time driver coil which accelerates the impulse engine exhaust gasses to near-light velocities, without achieving warp.

Warp drive reduces the ships overall mass, not impulse engines.

Quote:

Christopher wrote: (Post 2272860)
And of course no starship ever "stops," it just matches velocity with some other object in space or goes into orbit of some other body.

I meant 'absoute' in terms of reference to the vessels stationary relationship to other 'moving' bodies.

:techman:

Santaman November 9 2008 07:28 PM

Re: How do Starships stop?
 
Quote:

Manticore wrote: (Post 2272303)
I personally believe that the impulse engine is primarily a field drive, with only a limited thrust component, so slowing down would be fairly easy.

I agree with you on this one, the way starships move around does suggest the impulse drive is indeed a coil drive specialised to work at slower then light speeds, also it would explain the tremendoes acceleration and the little fuel it uses. .

USS KG5 November 9 2008 07:42 PM

Re: How do Starships stop?
 
Quote:

Santaman wrote: (Post 2273266)
Quote:

Manticore wrote: (Post 2272303)
I personally believe that the impulse engine is primarily a field drive, with only a limited thrust component, so slowing down would be fairly easy.

I agree with you on this one, the way starships move around does suggest the impulse drive is indeed a coil drive specialised to work at slower then light speeds, also it would explain the tremendoes acceleration and the little fuel it uses. .

Add me onto this list as well - the technology needed for the kind of manoevering we see on screen is better explained this way IMHO.


All times are GMT +1. The time now is 10:03 AM.

Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
FireFox 2+ or Internet Explorer 7+ highly recommended.