Maximum Impulse Acceleration

Discussion in 'Trek Tech' started by Thomas Kelvin, Nov 14, 2017.

  1. Thomas Kelvin

    Thomas Kelvin Ensign Red Shirt

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    So obviously, "full impulse" is not so much a speed as it is an acceleration. That being said, does anyone know of any canon impulse accelerations listed in the tech manuals or something?
     
  2. Timo

    Timo Fleet Admiral Admiral

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    The Tech Manuals probably should be inherently distrusted there. After all, the TNG one explicitly says it contains disinformation to fool Klingon spies!

    Generally, we get no solid numbers of the "initial speed, distance and time known" sort. But we can ballpark some accelerations well enough. At the beginning of the ST:TMP mission, the Enterprise leaves Earth orbit at impulse, and the planet recedes in main viewer view at what must be several hundred gees; no reason to assume any of this should be accounted to a simultaneous zoom-out.

    Or we can go by opposite outliers. In "Tin Man", the E-D is stalled when still "18 minutes" from its target at impulse, and remains stalled - but Data and the guest star reach the titular entity via transporter nevertheless. Is 18 minutes of impulse flight (be it constant acceleration and sudden non-Newtonian stop, or constant deceleration, or something in between) a pitiful 40,000 km or so?

    I gather there should be a set of limitations more complex than "maximum impulse is X gee" there, considering how close-quarters combat maneuvers never involve high accelerations whereas interplanetary travel or shuttle sorties commonly are very rapid.

    Also, sublight acceleration seems asymmetric, with the ships having easier time stopping than starting. Some sort of a subspace drag anchor built into the drive system, good for decelerating wrt the subspace frame of reference but no good for accelerating? This system would seem to be highly capable: in "BoBW", our heroes chase the Borg across the Sol system at such high impulse that their travel time estimates make them sound high relativistic (that is, apparently FTL, that is, massively time dilated), but they stop close to Earth in a heartbeat nevertheless, suggesting multi-thousand-gee decelerations.

    Timo Saloniemi
     
  3. matthunter

    matthunter Vice Admiral Admiral

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    If the inertial dampeners can handle standing start to Warp 9 and vice-versa, I don't think 0-full impulse is an issue.
     
  4. Samuel

    Samuel Fleet Captain Fleet Captain

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    Hasn't it been suggested that warp travel is inertia less (as it is by real science concepts today)?

    I seem to remember in the U.S.S. Enterprise-D Technical Manual it being stated that the Galaxy class ships could accelerate at up to 1,000 Gs. Whether that's disinformation or not I don't know.

    By the way, though traditionally we've come to believe that anything above 10-12 Gs is lethal to humans, research with animals has suggested that humans immersed in a liquid breathing medium could withstand up to 1,000 Gs WITHOUT physical injury.
     
  5. trekkist

    trekkist Lieutenant Red Shirt

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    Time and distance citations cited as Enterprise flees Reliant at end of WoK yields 18 gees (for a starship whose main reactor is offline, and whose impulse engines aren't being "directly fed" via the "deflection crystal").

    The teaser of "Conspiracy" features this interchange:

    RIKER: What is our e.t.a. at Pacifica, Mister La Forge?
    LAFORGE: Twenty two hours fourteen minutes, sir.
    RIKER: Increase to warp six.
    LAFORGE: Aye sir. Full impulse.

    I've seen LaForge's line described as a "joke." But he leaves the primary stationary in space towards end of "The Arsenal of Freedom," ordering Argyle to proceed to some Starbase or other. Many other proofs of ftl impulse capability exist.

    So: sublight acceleration, at least 18 gees for a refit. Max velocity of a Galaxy and refit (as per E's continuing to Regula and arriving prior rigor's onset after a 5 hr eta at warp, once warrp engines are offline): Warp factor six; acquisition of that velocity in a reasonable time would imply that when used ftl, impulse acceleration is FAR beyond 18 gees.

    That's canon, and I'm stickin' to it.
     
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  6. Samuel

    Samuel Fleet Captain Fleet Captain

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    I've seen it suggested that to reconcile all the things we've seen in Star Trek that Impulse power has to be

    1) The primary means of sublight propulsion (the most often thought of and on screen referred to use of it)
    2) Capable of providing faster than light propulsion in an emergency (too many episodes to count, beginning in "Where No Man Has Gone Before", including "The Paradise Syndrome" and various others).
    3) Capable of supplementing the Warp Engines. "Conspiracy", "The Corbomite Manuever" various others.
     
  7. Go-Captain

    Go-Captain Commander Red Shirt

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    In "Best of Both Worlds," if you assume a full stop near Jupiter from warp then the acceleration has to be over 10,000 g's, possibly 40,000 g, just going by memory, because they hit .96 c given the distance and stated ~40 minute travel time to catch up near Earth.
     
  8. Samuel

    Samuel Fleet Captain Fleet Captain

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    I thought it had been suggested it was possible for a starship to "transition" from warp speed to a rather high sublight velocity?
     
  9. Go-Captain

    Go-Captain Commander Red Shirt

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    I think the only indication starships maintain Newtonian speed is how the ships always appear to be moving relative to the camera when they drop from warp, maybe relative to DS9, too? There might be a statement in VOY about keeping a high Newtonian speed when dropping from warp.

    Based on how impulse has to work using warp fields to make any sense, I have nothing against the idea of a starship keeping an arbitrarily high speed once it drops from warp. But that means they have to have an arbitrarily high sub-light acceleration given it takes a few seconds to hit warp 1, and that puts it way beyond mere 10's of thousands of gravities of acceleration.
     
  10. Timo

    Timo Fleet Admiral Admiral

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    We might argue that impulse engines aren't doing anything during normal acceleration to warp, considering they were down for maintenance in "Obsession" when Kirk went to high warp. I mean, it would be very odd for Scotty to restart the impulse engines but in that process fail to deal with the vent he left open for the next Plot Complication.

    On the other hand, we may argue that impulse engines can and do go to very high relativistic speeds all on their own, as Kirk achieved this in ST:TMP but supposedly refrained from activating the all-new, untested warp engines until past Jupiter.

    Impulse resulting in FTL is not a real requirement in Trek, though. Nobody ever claimed that the E-D saucer would lack warp engines, so if (and when) she goes FTL, this is simply her going to warp. "Where No Man" never features FTL travel, just an explicitly short hop of "a few light days"; "Paradise Syndrome" seems to feature slow warp rather than fast impulse (because we have a yardstick in an inert asteroid, supposedly unequipped with warp drive); etc.

    Timo Saloniemi
     
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