Take an oscillating subspace field that reduces the inertial mass of the ship. Tune thrust "impulses" to the field minima, so as to "surf" out of the local field while able to transfer a relatively massive accelerative force smoothly to everything in the local field, reducing the load on inertial dampers by behaving as a field drive, though still utilizing the rocket principle. "Kitchen rudder" forcefields re-direct thrust pulses outside the ship as required, including thrust reversal. When I think of "impulse" drive, the above makes sense, though even with this high performance I agree that they should never need to acheive relativistic speed if the ship has warp drive. I've just assumed that much smaller distances than actual interstellar ones were involved when "limping" on impulse to a destination.
I think you may be implying a pattern from a singular example that sticks out in your mind. From my recollection, "trails/smoke" against a background was the exception, not the rule. The singular exception is Battlestar Galactica, in which the exhaust trails are limited ONLY to the afterburner effect of the vipers and never lingers for long. That wouldn't have been hard to do in the 1960s, considering those serials didn't depict rockets--or engines of any kind--in any real detail. I suppose Trek looked pretty sharp compared to, say, old Flash Gordon reels but if that's what Roddenberry was up against I kind of doubt he had something as complicated as a low-gear gravity drive in mind.
I don't understand why people have such a problem with this one. If the impulse drive reduces the mass of the ship or increases the local speed of light (or both, as Cary and I have both suggested on numerous occasions) then theoretically the ship could accelerate up to and beyond light speed by generating a strong enough subspace field around itself. An impulse engine that boosts the local C by a power of six could achieve several times the speed of light while only generating a few kps of "real" delta-vee. On the other hand, a subspace field warping C to a power of twelve ("Twelfth power energy? Thousands of starships couldn't generate that much...") could probably achieve velocities high enough to compete with warp-driven vessels. The only problem is an impulse engine used in this way would expend fuel at a fantastic rate, much faster than a more efficient warp drive at those speeds. And wouldn't you know it? Every time we have seen a ship traveling interstellar distances--or even maneuvering at high speeds--under impulse power, dialog has always mentioned concerns about fuel levels: whether it's a Romulan warship sneaking across the Neutral Zone or a Federation starship trying to outrun a flying wafflecone of death.
The TNG tech manual has a chapter on impulse engines. It basically comes down to deuterium-fueled fusion reactors generating plasma exhaust. I would guess (wildly) that a warp-like propulsion for sublight speeds would be a substantial waste of power.
I suspect this refers to some futuristic system of accelerating the exhaust products beyond lightspeed, as per experimentation described in the TNG TM. As for the name...well, maybe we're lucky they didn't say "mega-impulse."
From what material I've read, that's what they were responding or reacting to - "this is what we will not do" which included fiction, comics, books, and stuff NASA was doing. The point was to dissasociate the Enterprise with rockets people were familair with. At the same time, the impulse engine was compared to a conventional rocket. So it wasn't Newtonian or non-Newtonian - it was the LOOK of the rockets that was rejected, not the idea of the principle of Newtonian physics.
Didn't a Diane Duane novel call Impulse Internally Metered Pulse? As something WOT, I am entertained by the Johnny Slash GIF, Praetor. You are a big Square Pegs fan?
"Internally Metered Pulse," eh? I wonder what that would mean? (And I'm glad you like the av, Ronald Held. I am indeed a "Square Pegs" fan. )
I gathered that Praetor. I watch that series first run. I believe the IM pulse came from the concept of fusion of D/T pellets at some rate.
You know, YOU'RE to blame for that... I've had Johnny Slash quotes bouncing through my head for days now... and I know the only way to get rid of them is to go on Amazon and buy the damned "Square Pegs" DVD set. DAMN YOU!!!
Yet in NEM they did have something like an exhaust trail when the e-e fired its WARP engines. It sure didn't look like the lightstreak of past warps, or like anything else I can recall in TREK (pretty stupid looking as I recall.)
I don't know if it's been mentioned before, but Rick Sternbach has said that the impulse engines are not Newtonian, at least not as of TNG. http://drexfiles.wordpress.com/2009/05/14/holy-cow-2/#comment-9714
Well, that's interesting. I wonder why it's so important that impulse speeds be so fast, though? I can't think of any particularly good reason why more than a few hundred kilometers a second is dramatically necessary, when impulse is essentially just a method by which to maintain altitude in relation with a planet in the crazily close orbits starships like to take, and clear obstacles that could be damaged or damaging by going to warp too close to them. It's like insisting that a car have as many reverse gears as it does forward.
It wasn't in TOS, where the warp engines were used for just about everything and it wasn't explicitly codified (at least for writing purposes) that warp speed necessarily implied "faster than light." So we see this in episodes like "The Changeling" or "Elaan of Troyus" where a starship or other object traveling at warp speeds can take several seconds to cover a distance of only a few thousand kilometers. Later on, warp drive is an FTL-only system, with all the problems implied; this means warp drive becomes only the system used to move the ship long distances, but a lower-energy system is used for maneuvering and/or combat. You could actually think of it like modern jet combat: the F-22 Raptor can supercruise at Mach 2, but most jet combat takes place at around 400 knots anyway where supercruise won't make a lick of difference since climb rate, not raw acceleration, is more important in combat. Certainly things like the Picard Maneuver are the exception that prove the rule. If targeting sensors are limited to the speed of light (I see no reason why they wouldn't be) then combat FASTER than light would be tricky business for both parties.
I believe there are two things going on. The first is some confusion over when warp could be used. In TMP, it was dangerous to use warp inside a solar system (notwithstanding it would require FTL travel to get out of the system in a reasonable time to begin with, and the use of warp inside systems quite often in TOS). The second is that warp was costly to depict during TNG. They needed to have ships in normal space as much as possible so they didn't have to have the "warping" effect.
A plume, not a trail. Similar to the one we saw on the ENT-D's thrusters in "Booby Trap," similar to the ones we never see on the Enterprise's normal maneuvering thrusters despite cues for them in the script for TMP. One or the other; they are not the same thing. Likewise, there's an inverse correlation between exhaust velocity and the size/visibility of an exhaust plume. The exhaust plumes from an ion engine, for example, are virtually invisible; on the other hand, even the space shuttle's RCS thrusters do not leave a visible trail.