Why do almost all StarFleet ships have a Aft Ventral-Side Concave cavity on the StarDrive?

[Kamen Rider Blade]

It seems like most StarFleet designs incorporate this, yet other species don't seem have this in their designs.

The Borg especially manage to get away with moving faster despite being larger, more massive, and less "Sleek" for Warp Field Dynamics.

 

[matthunter]

It looks cool.

Aesthetics may be irrelevant to the Borg, but not to the Federation.

 

[Kamen Rider Blade]

So "Subjective" curvature for "Styling"?

 

[F. King Daniel]

The Borg ships are so powerful, they may be able to "brute force" higher warp speeds than the "warp-dynamic" Starfleet designs.

Although it begs the obvious question why no other known race uses the same shape if it's in some way practical for better warp speeds. It's one of those awkward areas where you just have to suspend disbelief.

 

[blssdwlf]

Starfleet branding guidelines.

 

[drt]

The Borg ships are so powerful, they may be able to "brute force" higher warp speeds than the "warp-dynamic" Starfleet designs.

Although it begs the obvious question why no other known race uses the same shape if it's in some way practical for better warp speeds. It's one of those awkward areas where you just have to suspend disbelief.

Yeah, if there was such a thing as warp dynamics everyone’s ships would look more similar. Although I guess we can maybe argue there’s some hand-wavium reason such as the different races having slightly different technologies being employed, like the Vulcans and their ring-ships. However, if a particular race seemed to have some sort of technological advantage, it seems like the other races would gravitate towards that technology/ship configuration.

 

[NewHeavensNewEarth]

Ultimately it's the "coolness" factor. But with all the times that Voyager went into planets' atmospheres or landed on surfaces, maybe there's meant to be an aerodynamic factor, too, for all Federation ships. You never know when all the transporters and shuttles will be down for maintenance.

 

[Kamen Rider Blade]

Starfleet branding guidelines.

That's one of the most believable reasons that I've seen yet.

 

[Kamen Rider Blade]

I don't think think it's for "WarpDynamic" reasons, Aircraft have certain design principles for "AeroDynamic" reasons.

That's why most Airliners are designed a certain way and look mostly the same when it comes to the big ones.

But since the "Warp Bubble" is established by many races using many configurations, the shape of the vessel structure doesn't seem to matter as much given the variety of different Warp Drive configurations that we've seen over the years.

The engine configurations to establish Warp Drive have come in so many flavors / forms, that the shape of the vessel doesn't seem to really matter as far as I can tell.

 

[Ithekro]

Might be Impulse Dynamics. Allowing a better mass drop for sublight travel.

On the other hand it might just be Warp Dynamics with Cochrane Drive ships (which all Starfleet ships still seem to use, regardless of Vulcan, Andorian, or anyone else's warp technology). Other nations have different solutions. Some might be more effective than others, or they just have the same feature, just it in a different location (effectively). With Cardassian ships, it might be the undercut on their bridge sections, or the pincer tails. On Klingon ships is might be a displacement upward by the structure that seems to be on the top of all their ships. The Romulans are working is a different system entirely so theirs could unfortunately be "inside" the ship, thus the huge space in the Warbird's center, refined to much thinner gaps in later ships.

 

[Kamen Rider Blade]

Might be Impulse Dynamics. Allowing a better mass drop for sublight travel.

That makes sense since there would be less structure, ergo easier to accelerate said mass of vessel.

On the other hand it might just be Warp Dynamics with Cochrane Drive ships

Could be, but I'm doubting it because the Klingons have vessels that have similar principles as the Federation, but in different physical configurations. Same with the Romulans.

Both don't seem to need it.

 

[Cyfa]

I seem to recall reading in one of the tech manuals (the TNG one, I think), that the undercut (helps to) prevents "pinwheeling", or something. I'll take a look and see what I can find. Of course, as I don't think it has ever been established on screen, any of the above reasons could be equally as legitimate

Edit: I've found it! From chapter 5 (Warp Propulsion Systems) of the TNG Technical Manual: "The aft hull undercut allows for varying degrees of field flow attachment, effectively preventing pinwheeling, owing to the placement of the nacelles off the vehicle Y-axis center of mass." Which is nice...

 

[Kamen Rider Blade]

I seem to recall reading in one of the tech manuals (the TNG one, I think), that the undercut (helps to) prevents "pinwheeling", or something. I'll take a look and see what I can find. Of course, as I don't think it has ever been established on screen, any of the above reasons could be equally as legitimate

Edit: I've found it! From chapter 5 (Warp Propulsion Systems) of the TNG Technical Manual: "The aft hull undercut allows for varying degrees of field flow attachment, effectively preventing pinwheeling, owing to the placement of the nacelles off the vehicle Y-axis center of mass." Which is nice...

What is "Pin-Wheeling"?

And Klingons / Romulans have many ships where the Warp Nacelles are hung from Pylons off to the side.

i don't see them having similar cuts in the hull.

 

[DonIago]

Theirs are cloaked.

 

[Ithekro]

The D7 has sort of an undercut on it.

 

[David cgc]

What is "Pin-Wheeling"?

The ship rotating rather than moving forward because the propulsive force is off-center. Like a pinwheel.

 

[Richard Baker]

IIRC in the episode 'Where none have gone before' you see the warpfield with the undercut contributing on the engineering monitor

 

[scotpens]

Original RL reason:

In-universe reason: Whatever floats your boat, in a manner of speaking.

 

[StarCruiser]

Yep, to echo the look of an old "Age of Sail" Frigate.

Star Trek was - after all - Hornblower in space.

 

[Kamen Rider Blade]

Yep, to echo the look of an old "Age of Sail" Frigate.

Star Trek was - after all - Hornblower in space.

The TOS StarShip design team was being a bit too literal then?