Reverse Impulse

[Kamen Rider Blade]

This is what I love about the Star Trek community, we're civil.

You look at sports fans, when they lose a big game; some of them riot and cause property destruction on a wide scale.

Here, we're all mature enough to agree to disagree & still respect one another.

 

[DanGovier]

This is what I love about the Star Trek community, we're civil.

You look at sports fans, when they lose a big game; some of them riot and cause property destruction on a wide scale.

Here, we're all mature enough to agree to disagree & still respect one another.

Quite right too. We all share a common love of Star Trek, and it's inevitable that there will be disagreements because even canon contradicts itself all the time. We all pick what feels best to us personally and that's totally fine

 

[Mytran]

That's just another reason why I love TOS the best; they didn't try and tie an explanation to every last piece of minutiae; many people can hold different interpretations and all can be right!

Except for me of course, I am the rightest

 

[Tenacity]

In the second pilot, nothing about "days away -> years away" suggests FTL impulse: quite the opposite, really, in making impulse several orders of magnitude slower than the default drive

The "days away -> years away" does in fact say that the impulse drive, while slower, is moving the ship at faster than light speed.

 

[Timo]

...How?

In TOS, as in all Trek, FTL travel with warp engines from star to another plot-relevant star takes hours (or more). At STL, stars by definition are years apart. Where does one get this "FTL STL" or "FTL impulse" here?

Do you feel Kirk should have said "decades away"? Sounds facetious to me. Decades are years, just as twenty hours is still hours.

Or is it something else? Do you feel there should have been no bases within lightyears/lightdecades? Why? As demonstrated, there was one just lightdays away. Apparently Kirk was to brave the Barrier at a spot well surrounded by supply assets, like any good explorer.

Is it something else still?

Timo Saloniemi

 

[goose814]

For me, when it comes to the Refit, I like the intent of the film makers of TMP. They wanted to make the ship more dynamic on film. That's why they had the main deflector change colors depending on speed. In addition to that, below warp, the impulse exhaust and crystal were lit and the warp engines were off. At warp, the impulse exhaust and crystal were off and the warp engines lit. In conjunction with that and like the main deflector, their intent was for the impulse exhaust and crystal to change color depending on speed. At lower impulse power settings they were to be red/orange and at higher impulse power settings they would be blue. You can see both exhaust and crystal are red/orange when they first go to impulse although we never got to see the impulse engines at a higher power setting during the film, however, the promotional photos of the Refit show the blue impulse exhaust.

Unfortunately, the film makers from TWOK and on disregarded that for simplicity's sake and just kept the main deflector blue, the impulse exhaust red/orange, and the impulse crystal blue. Although, for ST5, they used the blue impulse exhaust.

I do like the idea about the impulse exhaust being like a car exhaust and not for actual propulsion. I never thought of it like that but it makes more sense. As far as the RCS is concerned, I don't see that system as anything more than what it was intended for, which is directional control for the ship at sublight speeds. For propulsion below impulse speeds, I see the use of the maneuvering thrusters, which are located fore and aft on the secondary hull, for that purpose.

 

[Timo]

For me, when it comes to the Refit, I like the intent of the film makers of TMP.

Ditto.

Unfortunately, the film makers from TWOK and on disregarded that for simplicity's sake and just kept the main deflector blue, the impulse exhaust red/orange, and the impulse crystal blue. Although, for ST5, they used the blue impulse exhaust.

So in retrospect, we might argue that the gradual changing of color in TMP was because these systems were being brought on line for the very first time, and any subsequent activation would quickly result in "standard" colors.

And blue impulse in retrospect would be the sign of inferior performance or outright malfunction - as we observe it on the primitive ENT ships, on the badly wounded E-C (whose sister ships have standard red), and on the not-quite-operational E-A in ST5. Plus on some shuttles that arguably are of lower power than starships.

I do like the idea about the impulse exhaust being like a car exhaust and not for actual propulsion. I never thought of it like that but it makes more sense. As far as the RCS is concerned, I don't see that system as anything more than what it was intended for, which is directional control for the ship at sublight speeds. For propulsion below impulse speeds, I see the use of the maneuvering thrusters, which are located fore and aft on the secondary hull, for that purpose.

Since we so seldom see any flames from the RCS rockets, yet the ships maneuver intricately at sublight anyway, we might choose to believe in one further system, too. Something akin to gyroscopes today, perhaps, capable of turning and twisting the ship without actually creating any thrust or requiring matter to be expelled? Trek could do this with gravitics. Or then something that also generates a bit of thrust for translational movement. Why use the RCS rockets at all then, though?

Or then we could say that RCS only makes visible flames in circumstances X. But what would those be? The ship (I'm principally talking about the TNG era, where the hero ships have lots of screen time) can make tight turns without sprouting flames. The ship (now the Abrams/DSC realm) needs to sprout flames when dealing with the meager pull of a planet's gravity, though. The former probably ought to be the bigger feat... And nobody suggests the flames in Abrams/DSC visuals would be the sign of malfunctions or combat damage or the like. Or that the even bigger flames in "Booby Trap" would be, for that matter.

Timo Saloniemi

 

[goose814]

So in retrospect, we might argue that the gradual changing of color in TMP was because these systems were being brought on line for the very first time, and any subsequent activation would quickly result in "standard" colors.

And blue impulse in retrospect would be the sign of inferior performance or outright malfunction - as we observe it on the primitive ENT ships, on the badly wounded E-C (whose sister ships have standard red), and on the not-quite-operational E-A in ST5. Plus on some shuttles that arguably are of lower power than starships.

No, it didn't have anything to do with signs of malfunction. What I meant was whenever the impulse engines are brought on-line, at low power settings, they would be the red/orange color. As the power settings increased, they would start to change color to blue. If they throttled down again, then back to red/orange. It's the same concept that the main deflector had. At lower speeds the deflector was amber in color and at higher speeds it would change to blue because it was putting out more power to compensate for the increase in speed. Unfortunately, these features were dropped in subsequent movies to simplify filming along with several other lighting features that were used only during TMP.

Since we so seldom see any flames from the RCS rockets, yet the ships maneuver intricately at sublight anyway, we might choose to believe in one further system, too. Something akin to gyroscopes today, perhaps, capable of turning and twisting the ship without actually creating any thrust or requiring matter to be expelled? Trek could do this with gravitics. Or then something that also generates a bit of thrust for translational movement. Why use the RCS rockets at all then, though?

Or then we could say that RCS only makes visible flames in circumstances X. But what would those be? The ship (I'm principally talking about the TNG era, where the hero ships have lots of screen time) can make tight turns without sprouting flames. The ship (now the Abrams/DSC realm) needs to sprout flames when dealing with the meager pull of a planet's gravity, though. The former probably ought to be the bigger feat... And nobody suggests the flames in Abrams/DSC visuals would be the sign of malfunctions or combat damage or the like. Or that the even bigger flames in "Booby Trap" would be, for that matter.

Actually, the RCS system wouldn't put out any visible flames in space. If you watch when Spock's shuttle docks with the Enterprise, you can see the RCS thrusters glow brighter as they are being used to maneuver for docking. I read an interview with Andrew Probert once where he stated this was incorporated into the Refit model but I never saw any on-screen footage that showed it being used.

 

[Timo]

No, it didn't have anything to do with signs of malfunction.

Which is what I meant with my "in retrospect". That is, "taking into account later evidence", that is, reconciling with the fact that what we saw in TMP does not hold true for the rest of the appearances of that ship.

Associating blue with malfunctions or subpar performance is in keeping with the bulk of evidence. And associating TMP with malfunctions or subpar performance basically flows from the premise of that movie. Heck, Scotty thinks he needs four full days to drag that wreck of a ship from Earth to Vulcan!

Actually, the RCS system wouldn't put out any visible flames in space.

Which is why it's weird when it does, and very prominently so, in TNG and DS9 and the new movies and DSC all.

And weirder still that it doesn't do that all the time, but only on certain occasions.

If you watch when Spock's shuttle docks with the Enterprise, you can see the RCS thrusters glow brighter as they are being used to maneuver for docking. I read an interview with Andrew Probert once where he stated this was incorporated into the Refit model but I never saw any on-screen footage that showed it being used.

There were all sorts of blinkies on the models, some working appropriately for their intended role, some most probably not. If the Vulcan shuttle RCS glow was done with blinkies rather than in postproduction, then it's all the likelier IMHO that it would have been omitted from the big ship because of complexity (and fans would in any case still be pointing out they lit up all the wrong thrusters for the observed movement!).

Personally, I find it pretty repulsive how Star Trek technology was downgraded so drastically for TMP, basically becoming 1970s NASA and making it quite implausible that these ships could ever make it to the stars. Airlocks, docking ports, steering rockets... Why not staged propulsion while they are at it, with jettisonable fuel tanks at the very least, and rocket stages falling off the hero ship as she accelerates away from Earth at worst? But invisible RCS even if from visible nozzles is somewhat palatable, and in keeping with how no glow of any sort was previously or later required for making these ships turn in space.

Timo Saloniemi

 

[Pauln6]

See, I'm the opposite. I love that TMP added more definition to the limits of the technology. The more magical you make it the harder it becomes to tell a story of human endeavour.

The ships do have tractor/pressor beams, although these could be electromagnetic. Certainly any gravitational technology they have is limited given that they can't shift a large asteroid by much.

I've always assumed conventional thrusters were used for atmospheric landing, partly due to the toxic output of Impulse engines, and that as a result, starships were too large and not aerodynamic enough to enter the lower atmosphere. Otherwise why remain in orbit and use shuttles or transporters (especially when you can use transporters to travel light years now :-/ ).

That said, it makes sense that, in an emergency, there would be some mechanism to avoid a catastrophic planetary crash and using a graviton based pressor beam to reduce the velocity of the ship might be possible but there must be a reason why we don't hear them using this to land regularly. It must be energy prohibitive, dangerous to use in an atmosphere, or something.

I was watching a TOS episode last week where Scotty mentioned that Impulse fuel would be exhausted in 7 hours at high speeds. That certainly implies that more fuel is required for high speeds. Of course, energy would be needed to generate gravitons too so fuel would be required either way. If Impulse thrust was graviton based though I don't see why you couldn't just use the warp engines to provide the energy you need.

 

[Mytran]

If Impulse thrust was graviton based though I don't see why you couldn't just use the warp engines to provide the energy you need.

Because in the episode you quoted (which I assume was The Doomsday Machine) the warp engine pods had been deactivated

 

[Pauln6]

Because in the episode you quoted (which I assume was The Doomsday Machine) the warp engine pods had been deactivated

Thanks, I watched a few on catch up and I couldn't recall which one it was. I meant more generally but if the warp pods are offline I suppose both sides of the argument are still up for grabs. They don't often travel far on impulse power because they have no need to.

If I recall though, in Elaan of Troyus, there is a suggestion that the impulse engines were not capable of powering the shields for long under fire. Seems unlikely they could power a graviton based emitter over any distances.

I suppose the upshot is that impulse travel is next to useless anywhere other than in a solar system. You might as well just use them to power your life support for longer and wait for rescue.

 

[Mytran]

Good summary. To quote Scotty on the Impulse Engines:

Aye. We can wallow like a garbage scow against a warp-driven starship...Our shields will hold for a few passes, but without the matter-antimatter reactor, we've no chance!

Interesting that in both TDM and EOT, Impulse Engine fuel is consumed rapidly when deprived of the main warp engines

 

[blssdwlf]

Good summary. To quote Scotty on the Impulse Engines:
Interesting that in both TDM and EOT, Impulse Engine fuel is consumed rapidly when deprived of the main warp engines

Actually fuel usage on impulse under emergency conditions (ie loss of warp drive) is pretty consistent among the episodes. "Where No Man Has Gone Before" and "Mudd's Women" showed that it's a one-way trip with no chance of leaving orbit of their destination planet due to a lack of fuel. This suggests that there is only enough impulse fuel to accelerate, cruise and decelerate to one location in emergencies. "The Doomsday Machine", "Elaan of Troyius" and "The Immunity Syndrome" compounds the situation by forcing multiple acceleration maneuvers for evasion and power to shields/tractors/etc which use up the remaining impulse fuel even faster.

 

[Johnny7oak]

you reverse the sequence on the nacelle stages. 1-2-3-4-5, becomes, 5-4-3-2-1 or on a band nacelle you glide active zone reversely.

 

[Jedi Marso]

Any technology that allows you to generate artificial gravity fields or dampen inertia negates the need for rocket-style propulsion. If you can generate gravity fields, you can move objects through space in any direction you want, in or out of planetary gravity wells.

Trek contradicts itself on many subjects in many ways. 'Impulse propulsion' and what it actually means is definitely one of them.

 

[Timo]

I don't quite follow. What you describe in the first paragraph is what we see in Trek, after all. Where's the contradiction? (In the backstage books?)

Timo Saloniemi

 

[Pauln6]

Any technology that allows you to generate artificial gravity fields or dampen inertia negates the need for rocket-style propulsion. If you can generate gravity fields, you can move objects through space in any direction you want, in or out of planetary gravity wells.

Trek contradicts itself on many subjects in many ways. 'Impulse propulsion' and what it actually means is definitely one of them.

It's true that if a pressor/tractor beam can push or pull an object then it can push or pull your ship where the mass of said object is greater than the mass of your ship.

There are also limitations. The field generated by the emitters is narrow and not omnidirectional. I struggle to see how it it might be used to steer a ship in an atmosphere. The ship had insufficient power to divert the asteroid in the Paradise Syndrome and burned out its systems in the attempt.

I suppose the mass of the individual objects to be affected by artificial gravity and inertial dampening is generally low.

 

[Mytran]

Any technology that allows you to generate artificial gravity fields or dampen inertia negates the need for rocket-style propulsion. If you can generate gravity fields, you can move objects through space in any direction you want, in or out of planetary gravity wells.

Trek contradicts itself on many subjects in many ways. 'Impulse propulsion' and what it actually means is definitely one of them.

Are you perhaps confusing weight with mass? Even in a zero-g environment, an object will still have a certain mass and require a specific amount of kinetic energy to push it

 

[blssdwlf]

Any technology that allows you to generate artificial gravity fields or dampen inertia negates the need for rocket-style propulsion. If you can generate gravity fields, you can move objects through space in any direction you want, in or out of planetary gravity wells.

The creature from "Obsession" used gravity fields for FTL and sublight propulsion so in some sense early Star Trek writers understood that possibility. I suspect that for TOS and possibly Star Trek in general that ship technology do not or can not use gravity fields exclusively to propel the ship. Space warp and Impulse use something else or a combination of systems to allow for the fantastic speeds, IMHO.