Markings on saucer section of NCC-1701

[Captain Robert April]

"Landing" is probably the wrong term in this case. More like a controlled crash, since we're talking the ultimate in last ditch maneuvers.

In that scenario, the lower sensor dome would be considered a loss before they even hit atmo, so no point in ejecting it; might as well use it to break the fall.

As for the neck, it probably has a series of crumple zones and breakaway sections, so that uneven ground is less of a concern.

Again, I don't think any thought at all was put into what purpose those triangles served, aside from what Shaw said, to keep Roddenberry happy and out of their hair. The idea of landing the ship was ditched veerrrrrrrry early on, possibly even before Jefferies was hired, or around that time, simply because it was a given that landing the ship, any ship, at that time would be prohibitively expensive (notice we only saw the shuttlecraft take off and land in the hangar bay, and never on a planet; why? It's cheaper, and even then, it was just recylced "Galileo Seven" footage). Even that first format proposal said the ship "rarely lands on a planet", so even then there weren't any plans to do it much, if at all.

Once the design started getting bigger than a typical Navy destroyer, I think it's safe to say that any ideas of landing the ship in any way, shape, or form, was tossed out the airlock.

 

[Timo]

Then again, the ship did demonstrate the ability to maneuver effortlessly in an atmosphere or a gravity field, or to perform extreme accelerations. So consistency would call for her being able to land on planets and take off, in a controlled manner, even in emergencies.

Having the saucer do the 1950s UFO thing with "tiptoe" legs would well express the mastery of technology and materials that must lie behind all Trek engineering. It would look like science fiction, which IMHO is a good thing. Say, the allure of the transporter lies in its utter un- or surrealism, too, not in its mimicry of real-world engineering solutions or limitations. In scifi, verisimilitude often means fantasy rather than realism.

Timo Saloniemi

 

[Santaman]

Once the design started getting bigger than a typical Navy destroyer, I think it's safe to say that any ideas of landing the ship in any way, shape, or form, was tossed out the airlock.

Oh there's definitly a reason for not wanting for example a Galaxy class attempting to land, there's this issue of something that large flying around in a atmosphere at anything beyond very low speeds causing massive pressure waves and the like that will make a F5 tornado look like a fart after you've eaten some spicy chinese food, and if there's going to be a sonic boom then it will probably blow out every window in a 300 mile radius, also there's the thing of finding a parking spot... besides these issues I have no problem with any class of Fed ship being able to land.

 

[Praetor]

Then again, the ship did demonstrate the ability to maneuver effortlessly in an atmosphere or a gravity field, or to perform extreme accelerations. So consistency would call for her being able to land on planets and take off, in a controlled manner, even in emergencies.

Having the saucer do the 1950s UFO thing with "tiptoe" legs would well express the mastery of technology and materials that must lie behind all Trek engineering. It would look like science fiction, which IMHO is a good thing. Say, the allure of the transporter lies in its utter un- or surrealism, too, not in its mimicry of real-world engineering solutions or limitations. In scifi, verisimilitude often means fantasy rather than realism.

Timo Saloniemi

I tend to agree. There's a fine line between having something seem inexplicable even within the rules of a given universe, but I don't think that crosses that line. Myself, I like when the technology is allowed to impress us a bit.

 

[Captain Robert April]

Then again, the ship did demonstrate the ability to maneuver effortlessly in an atmosphere or a gravity field, or to perform extreme accelerations. So consistency would call for her being able to land on planets and take off, in a controlled manner, even in emergencies.

I wouldn't say "effortlessly". The only time we ever saw the Enterprise maneuvering in an atmosphere, Sulu described the ship as being "sluggish", Spock specifically said that they couldn't maintain orbit at that altitude, and while everyone was still out cold on the decks, the ship was struggling on automatic to stay up.

The ship was not designed to operate within a planetary atmosphere. Period.

 

[Vance]

You mean where it was damaged from an accidental warp slingshot, April? :P

Hardly fair, considering... we don't know how much of an issue the ship was having due to the damage the engines took.

 

[Search4]

If i might say so - given the presence of thrusters, impulse power, anti-gravity units, inertial dampers, and other devices that could be configured to help with flight, I'd be very happy to believe that the saucer at least would be manueverable in the atmosphere and that the markings could be landing legs of some type.

By the way, i'm surprised no one has shown "wheels" for use on a run way of some type.

In terms of "sluggish in the atmosphere", that was a pretty clear reference to the ship's condition post-slingshot, and of course to compare the Enterprise's "sluggish" with the aircrafts "she's moving away rapidly".

 

[Cary L. Brown]

If i might say so - given the presence of thrusters, impulse power, anti-gravity units, inertial dampers, and other devices that could be configured to help with flight, I'd be very happy to believe that the saucer at least would be manueverable in the atmosphere and that the markings could be landing legs of some type.

By the way, i'm surprised no one has shown "wheels" for use on a run way of some type.

In terms of "sluggish in the atmosphere", that was a pretty clear reference to the ship's condition post-slingshot, and of course to compare the Enterprise's "sluggish" with the aircrafts "she's moving away rapidly".

Actually, it makes perfect sense for the ship not to be particularly maneuverable in an atmosphere... it's not like there's an aerodynamic fairing over the entire ship, and there's gonna be a LOT of vortexing happening around the various "sharp intersections."

It's not designed as an aircraft. It is, simply, not aerodynamic. Nor is it supposed to be. It's a PRESSURE VESSEL.

On the other hand... the saucer, by itself, might not have so many problems. While it will not generate aerodynamic LIFT, it should be able to "fly" reasonably well if it has anti-grav lift.

 

[Birdog]

On the other hand... the saucer, by itself, might not have so many problems. While it will not generate aerodynamic LIFT,

Why not? It's in essence a Frisbee. That puppy would fly real nice without having to go very fast at all.

 

[Forbin]

The concave undersurface is there for "camber," to help provide lift.

 

[Birdog]

The concave undersurface is there for "camber," to help provide lift.

Technically camber is on the upper surface of an airfoil but you have the basic concept right.

 

[Cary L. Brown]

The concave undersurface is there for "camber," to help provide lift.

Unfortunately, that's not how it works.

Look at a traditional airfoil. What you'll notice is that the distance from the leading edge to the trailing edge is LONGER on the top surface, and SHORTER on the bottom surface.

This means that the velocity of air is higher, along the surface of the airfoil, on the top than on the bottom.

Without getting too geekishly technical, and without quoting various "laws" by the name of the guy who invented them (most folks here won't care!)... just realize that there is an inverse relationship between velocity and normal pressure.

SO... because, and ONLY because, the distance that the air is travelling along that surface per unit time is greater on the top than on the bottom, there is a pressure differential between the top and the bottom.

This is the concept behind how and airfoil creates lift. Not "part" of the concept... it's the whole concept.

SO... by creating this feature on the UNDERSIDE of the primary hull, it does not provide additional lift. In fact, it does exactly the opposite. It creates "negative lift"... pulling the saucer downwards... compared to what you'd have if the saucer had a perfectly flat underside instead of that "camber."

The issue is always... shorter distance per time = higher pressure. Longer distance per unit time = lower pressure.

Remember that we're talking not about the length of the surface, but rather the distance that air molecules are moving along that surface, and always measured in relationship to the direction of travel through the air - if the air is moving too - say, you have wind, or an "updraft" or "downdraft"... you have to take that into account.

Now, there are other issues that also go into the design of a wing or other airfoil, including weight and mechanical strength. For this reason, you'll often see an "undercut" on the underside as well (much like the "hollow" inside of a frisbee underside).

The trick is to realize that the air flow doesn't exactly follow the surface... inside the "hollow," the air is (relatively) still, and doesn't flow at full velocity along the inside surface. This is done for MATERIAL SAVINGS, or for mechanical strength in torsion... not to improve lift. You'd still be better off, from "airfoil theory", to have a the shortest possible length you can have (ie, a flat plane).

The other issue that comes into play, and why we almost never see a truely flat-undersided airfoil, has to do with turbulence. A smooth, blended surface is less likely to see the flow of air become discontinuous as you change angle-of-attack... less likely to "stall," in other words.

(Note that airfoil-lift isn't the only source of "lift" in an aircraft, of course... though it is normally the principle one. You also get a certain degree of "lift" simply by having a positive angle-of-attack (you can play with this by sticking your hand, flat, out the car window while driving!). And thrust may have an upwards directionality as well, which is technically "lift" from the standpont of the aircraft.)

Basic starting point - http://en.wikipedia.org/wiki/Airfoil

 

[Birdog]

The concave undersurface is there for "camber," to help provide lift.

SO... by creating this feature on the UNDERSIDE of the primary hull, it does not provide additional lift. In fact, it does exactly the opposite. It creates "negative lift"... pulling the saucer downwards... compared to what you'd have if the saucer had a perfectly flat underside instead of that "camber."

Frisbee? You're forgetting that the upper surface of the saucer is convex and that this thing would most likely fly with a fair bit of Alpha. Also anything will fly and generate lift with enough thrust behind it. The cross section of the saucer is much like the third airfoil shown here http://www.allstar.fiu.edu/aero/images/fig18.gif

 

[Forbin]

Dude, you don't have to explain airfoils to me - just keep in mind that it's fiction, and that it's SUPPOSED to work like that in the fictional Trek universe.

 

[Timo]

As many have mentioned, the very fact that the ship stayed stable in an atmosphere while riding on a damaged autopilot should speak well of its atmospheric capabilities. But those are sort of secondary to my original argument: a ship equipped with an impulse drive and the mass-altering, inertia-damping or structure-strengthening abilities needed for impulse drive should be able to skip aerodynamics and do whatever she wishes.

Flying through air or water should be a breeze. The problem isn't in inventing ways by which starships could maneuver in atmospheres. It lies in inventing limitations that would explain why they don't maneuver within solid rock more often.

As for the undercut of frisbees, that's there basically because the disk has to be curved on the upper side but OTOH is manufactured from a plastic sheet of constant thickness. The aerodynamics would work pretty well if the underside was completely flat, as Cary describes, but that would have two major downsides. First, more plastic would be needed (as already mentioned by Cary), and the thing would need to be hollow for lightness, but making a hollow shape is much harder than making a bowl. Second, how would one grip the thing for throwing? Thus, the undercut is left there, more or less coincidentally rather than intentionally.

Timo Saloniemi

 

[Cary L. Brown]

Frisbee? You're forgetting that the upper surface of the saucer is convex and that this thing would most likely fly with a fair bit of Alpha.

I'm not "forgetting" anything. My point is that the ship would have LESS total lift with the "undercut" than without it, due to what I pointed out.

Also anything will fly and generate lift with enough thrust behind it.

Not really, no... "thrust" isn't the same as "lift" in this sense (though I did mention the benefit of a slightly-upwards thrust providing some "lift" in my post). A brick will never generate "lift" in the aerodynamic sense. Doesn't mean you can't make it fly, just that you can't make it generate aerodynamic lift.

The cross section of the saucer is much like the third airfoil shown here http://www.allstar.fiu.edu/aero/images/fig18.gif

Not really. Again, the trick when looking at that airfoil in image #3 is to note that the distance from the leading edge to the trailing edge, along the surface of the wing cross-section, is much greater on the top than on the bottom surface.

THAT IS WHAT CREATES AERODYNAMIC LIFT.

My point was that the undercut doesn't help lift... not in the slightest. It has the opposite effect.

Whatever the purpose of the undercut is, it's NOT to make the saucer fly better in an atmosphere.

However... consider another point I made - that of "resistance to torsion." Many very light aircraft use wings of the form illustrated in "image #3" from the above link. Why? because they're more resistant to torsion along the length of the wing than a "straight" wing section is.

The "saucer" of the 1701 is pretty flimsy, sure, but I suspect that it would gain a great deal of torsional resistance (ie, reduction of the amount of "edge flappiness") by having this sort of structure.

Sure, you could gain even MORE by having that section be two decks thick all the way through, but you'd be adding a great deal more MASS in the process than you do with this undercut.

Oh, and Forbin, I know you get it... but I don't want anyone who has no training in this field to "learn" things wrong.

 

[Timo]

Whatever the purpose of the undercut is, it's NOT to make the saucer fly better in an atmosphere.

...Although it might still be vaguely related to aerodynamics - say, it could work as part of a landing cushion system that traps an air bubble beneath the saucer at the crucial moment. Not alone, not simply by its shape, but perhaps with some sort of air curtains?

The structural strength argument is better, although you'd get the same effect plus more volume if instead of concavity, you did convexity. Whether more volume (and more mass) is a bad thing or a good thing would depend...

Timo Saloniemi

 

[JuanBolio]

"Landing" is probably the wrong term in this case. More like a controlled crash, since we're talking the ultimate in last ditch maneuvers.

In that scenario, the lower sensor dome would be considered a loss before they even hit atmo, so no point in ejecting it; might as well use it to break the fall.

Sure, landing the saucer would be a last-ditch maneuver, but why design it so that the sensor dome must be ejected or crushed when you could simply make the landing legs a little longer?

 

[Maurice]

Orrrr...maybe the undercut is there for style and nothing else.

 

[Birdog]

Mr. Brown,
I think you have a flawed understanding of what causes aerodynamic lift that came from the way it's taught in elementary school. Lift is not entirely caused by the higher velocity of fluid on the upper surface. Yes Bernoulli's principle does tell us that a faster fluid has a lower pressure. Most of the lift on an airfoil is caused by flow turning. They way you explained an airfoil does not allow for inverted flight. An airfoil DOES NOT have to have a longer surface on top. As a matter of fact the supercritical airfoil has the longer surface on the bottom. http://www.aerospaceweb.org/question/airfoils/supercritical/whitcomb.gif

You'll want to read this NASA page, they can explain it better than I.
http://www.grc.nasa.gov/WWW/K-12/airplane/wrong1.html

The point I was trying to make earlier is if you can get it to move with enough airspeed and give it an angle of attack then it will produce lift.