How big SHOULD the Defiant be?

[matthunter]

Type-6 shuttle in size (which is canonically either 10x slower or 10x slower to accelerate than the stated norms for starships)

Source?

 

[Shamrock Holmes]

Source?

https://memory-alpha.fandom.com/wiki/Impulse_engine


In The Motion Picture, The Enterprise traveled at warp 0.5 from Earth to past the planet Jupiter, a distance of (at a minimum) 390,674,900 miles, in 1.8 hours, making that speed approximately equal to 97,026 kilometers per second (217,041,611 miles per hour), or roughly 1/3 light speed. The difference may be explained by differences in orbital precession between the two planets at the time, or, as with warp drive, there may be other variables involved.

According to Jo'Bril in the episode "Suspicions", "I am one million kilometres from the star's corona. Proceeding at three quarters impulse. I should reach it in approximately three minutes." That is approximately 12,400,000 miles per hour or 5,543 kilometers per second (~1.8% the speed of light). One quarter impulse for the shuttle could be estimated at 1,852 kilometers per second.

The Star Trek Voyager Technical Manual, page 13, has full impulse listed as ¼ of the speed of light, which is 167,000,000 mph or 74,770 km/s. One quarter impulse for Voyager would be 18,665 km/s. Voyager's one quarter impulse is 10 times faster than that of the shuttle. Therefore, the term "¼ impulse" isn't a fixed speed as much as it is one fourth of the full speed of the impulse engines' maximum.

 

[Timo]

...Or, since there is no body of data to tie the "impulses" of a given starship to given speeds (save for these single pairings, some of which are listed above, and none of which can be used to plot a speed vs. impulse line on a chart), we can completely drop the idea that an "impulse" would have anything to do with speed.

The actual usage would be rather more naturally interpreted as throttle settings: zero impulse is idle, full impulse is all out, and if a big engine on a small ship does 1/4 impulse for two minutes, it is gonna outrun a big ship that does 1/2 on its small engine for two days.

And, on the other hand, a ship doing 1/4 impulse may be crawling for the first minutes of its journey, and licking lightspeed after a few hours... Both of which are things associated with "1/4 impulse" in dialogue, even if never for one and the same ship/engine.

Timo Saloniemi

 

[Shamrock Holmes]

we can completely drop the idea that an "impulse" would have anything to do with speed.

It's clear that there's some sort of relationship. However, it's also clear that like warp speed values, impulse values are not fixed.

The actual usage would be rather more naturally interpreted as throttle settings: zero impulse is idle, full impulse is all out, and if a big engine on a small ship does 1/4 impulse for two minutes, it is gonna outrun a big ship that does 1/2 on its small engine for two days.

Throttle settings are either a measure of speed (which "impulse" doesn't appear to be in a fixed sense) or of acceleration. Both have an impact on relative and achievable speed.

And relative speed is a key factor in maneuverability and evasion.

and if a big engine on a small ship does 1/4 impulse for two minutes, it is gonna outrun a big ship that does 1/2 on its small engine for two days.

Even if that's true, and I doubt it, that's irrelevant to this point as we're talking about a small ship with a small engine, against a big ship with a big engine because whatever the figure means, the bigger figure is still faster.

For similar reasons, the Connie would be able to match if not outmaneuver the Intrepid because they are a similar size, but the newer ship has greater mass and slower engines.

 

[matthunter]

1/4 impulse isn't consistent even on the same ship - the Enterprise rockets away from Earth in TMP, but only manages a leisurely saunter away from Spacedock whilst being stolen in TSFS.

Hell, if the acceleration seen in TMP is consistent, there'd be no need for a regulation to stop Captains/Admirals ordering 1/4 impulse in Spacedock for the same reason you don't need a regulation against ramming your head into a wall.

 

[Shamrock Holmes]

1/4 impulse isn't consistent even on the same ship - the Enterprise rockets away from Earth in TMP, but only manages a leisurely saunter away from Spacedock whilst being stolen in TSFS.

Hell, if the acceleration seen in TMP is consistent, there'd be no need for a regulation to stop Captains/Admirals ordering 1/4 impulse in Spacedock for the same reason you don't need a regulation against ramming your head into a wall.

Yeah, those scenes kinda sorta work if it's supposed to be acceleration, but as a measure of fixed speed... no way.