Suggestion, Super-streamlined, and Lifting hulls.

[phavoc]

Drag. Drag is fighting against them.

Drag is an aerodynamic concept....

Control issues are easily resolved through computerized control systems; not an issue so long as you have Thrust to spare for control. See flying wings. Additionally, designers design and pilots fly their ships for their intended purpose.

Nasa flies the X-29, which can ONLY fly because a computer controls the aircraft. That's a far better example than a flying wing, as the first flying wings had ZERO computer controls. But forward-swept wing aircraft can't even get off the ground without computer control.

Regardless of your thrust capability you still run into the idea that the faster you travel the more power is required to simply maintain your speed.

While you are not technically wrong, you are failing to grasp the concept. Drag is opposed by Thrust. Drag is a function of Speed. So while Power may be Thrust times Speed, Power is a red herring here. If your Thrust exceeds your Drag, you go faster.

You mean fighting the Drag with Thrust, and fighting the control issues with Thrust.

Not quite. You can't fight every control issue with just thrust. Not efficiently at least. That's why you have aerodynamic designs to minimize drag so you can more efficiently use the energy available to you, for things like thrust.

The point at which you reach diminishing returns is when the Drag is equal to the Thrust. Control issues if you do not have Thrust to spare for correction.

We're both saying the same thing here.

No. Right Angles are not the right choice. Triangles everywhere; that's how you get your space frames. Easily very geodesic. Which can get you your very smooth domes, and can get you wing-shapes; not that you really want them, but you can have them if you're into that sort of thing. At that point, you apply a smooth skin, and put in a light-weight filler to back up the gap between the frame joints. Then you apply armor.

This implies that your cargo storage mediums would become triangular as well to fit within your craft (though not always). Much depends on scale here. The larger your scale the easier it is to blend in any of the shapes. But if I'm trying to design a small craft that can carry a single 10Dton container then I couldn't make it triagular - unless I broke the triangles down into very small portions and built up from that. In this case a cube just a tad larger than my 10Dton container with engines and a control cabin slapped on is the optimum size and shape.

 

[Tenacious-Techhunter]

Drag. Drag is fighting against them.

Drag is an aerodynamic concept....

The vaguely-described forces you were talking about fighting with the spacecraft were all drag.

That's a far better example than a flying wing, as the first flying wings had ZERO computer controls.

No, the flying wing is a perfectly fine example; you just don't know their history. Flying wings always had control problems, and had to be flown by exceptional test pilots. Northrop had to give up on them because there wasn't a suitable control system to overcome their control issues. While the examples you quote are adequate as extreme examples, we weren't discussing extreme limits of theoretical performance here.

Regardless of your thrust capability you still run into the idea that the faster you travel the more power is required to simply maintain your speed.

While you are not technically wrong, you are failing to grasp the concept. Drag is opposed by Thrust. Drag is a function of Speed. So while Power may be Thrust times Speed, Power is a red herring here. If your Thrust exceeds your Drag, you go faster.

You mean fighting the Drag with Thrust, and fighting the control issues with Thrust.

Not quite. You can't fight every control issue with just thrust. Not efficiently at least. That's why you have aerodynamic designs to minimize drag so you can more efficiently use the energy available to you, for things like thrust.

I never said it was efficient. I said it was possible. Muscle Cars are not efficient. But they still perform well, poor efficiency notwithstanding. Overcoming drag with thrust rather than streamlining is not an efficient choice, but it's still perfectly feasible, and will perform well enough. If a culture simply hasn't developed advanced streamlining, they can get by without it, if they have power to waste.

The point at which you reach diminishing returns is when the Drag is equal to the Thrust. Control issues if you do not have Thrust to spare for correction.

We're both saying the same thing here.

No; we're both meaning the same thing, but you're failing to understand the meaning of what I say, and then saying something different while failing to convey the same meaning.

No. Right Angles are not the right choice. Triangles everywhere; that's how you get your space frames. Easily very geodesic. Which can get you your very smooth domes, and can get you wing-shapes; not that you really want them, but you can have them if you're into that sort of thing. At that point, you apply a smooth skin, and put in a light-weight filler to back up the gap between the frame joints. Then you apply armor.

This implies that your cargo storage mediums would become triangular as well to fit within your craft (though not always). Much depends on scale here. The larger your scale the easier it is to blend in any of the shapes. But if I'm trying to design a small craft that can carry a single 10Dton container then I couldn't make it triagular - unless I broke the triangles down into very small portions and built up from that. In this case a cube just a tad larger than my 10Dton container with engines and a control cabin slapped on is the optimum size and shape.

It implies no such thing. The Space Frames are what make up the structure of the hull; the inside can be whatever shape you want. Now, granted, in theory, tetrahedral cargo containers would be the most structurally sound for their weight; but we can afford additional weight, so that doesn't matter.

 

[MongooseMatt]

But forward-swept wing aircraft can't even get off the ground without computer control.

I don't have the photo to hand, but I actually built a forward-swept wing aircraft (r/c, natch).

Even in my hands, it flew alright

 

[phavoc]

But forward-swept wing aircraft can't even get off the ground without computer control.

I don't have the photo to hand, but I actually built a forward-swept wing aircraft (r/c, natch).

Even in my hands, it flew alright

Lol! Maybe you should join NASA then. They need geniuses like you!

 

[MongooseMatt]

I cannot find the one I did online either (I built it from a plan). However, you can get commercial ARTFs with forward-swept wings;

The one I did had a much more pronounced sweep and thinner chord. Need to find that photo...

 

[Tenacious-Techhunter]

The length of the wing may contribute to its stability.

 

[Condottiere]

I recall foam aluminum was proposed as an alternate building material.

It sounds light enough.

 

[MongooseMatt]

Still can't find that photo (starting to annoy me), but I did find this, which gets the point across, I think

 

[phavoc]

The only problem is that the models have thrust-weight ratios the real things can't replicate. They look cook, just aren't useful comparisons.

 

[Tenacious-Techhunter]

Foam Aluminum; between the spaceframe and the hull surface, you mean? Carbon foam is also a thing...

 

[Tenacious-Techhunter]

Thrust-to-weight-ratio is accounted for by the displacement to Maneuver Drive table. While more detail would be better in theory, this compromise is already canon, and saves us from having to care about the cargo's mass.

 

[wbnc]

The only problem is that the models have thrust-weight ratios the real things can't replicate. They look cook, just aren't useful comparisons.

You would be surprised. The small scale model was the first step of most designs before computer testing. the numbers are different but the principles enforce themselves with equal vigor.

ya tweak the engine to get ore power, it tends to overload the air-frame, or cause control problems..Such as my Buzzard bombshell that would climb uncontrollably since the power/lift to weight was TOO high...

I had to cant the engine downwards to compensate...add more drag and down force...using the power of the engine to add down force...couldn't afford a better motor at the time. if you want a model that flies like you want it too, you have to build them to almost the same proportions, and ratios, as a full scale plane.

Of course you CAN get away with much sloppier numbers on a scale model...since if it fails a crash results in some tape, and a bit of balsa wood replaced....not a smoking hole in the desert.

 

[phavoc]

The only problem is that the models have thrust-weight ratios the real things can't replicate. They look cook, just aren't useful comparisons.

You would be surprised. The small scale model was the first step of most designs before computer testing. the numbers are different but the principles enforce themselves with equal vigor.

ya tweak the engine to get ore power, it tends to overload the air-frame, or cause control problems..Such as my Buzzard bombshell that would climb uncontrollably since the power/lift to weight was TOO high...

I had to cant the engine downwards to compensate...add more drag and down force...using the power of the engine to add down force...couldn't afford a better motor at the time. if you want a model that flies like you want it too, you have to build them to almost the same proportions, and ratios, as a full scale plane.

Of course you CAN get away with much sloppier numbers on a scale model...since if it fails a crash results in some tape, and a bit of balsa wood replaced....not a smoking hole in the desert.

Yup, too MUCH power for a scaled aircraft (or model rocket) isn't uncommon at all. That's why models and such can only take you so far until you have to build and test out all your theories on the 1:1 model. Computer simulations have helped that a lot since the days of sliderules, but no matter how well you simulate or build a model, you still need to prove it in flight or action.

 

[wbnc]

Yup, too MUCH power for a scaled aircraft (or model rocket) isn't uncommon at all. That's why models and such can only take you so far until you have to build and test out all your theories on the 1:1 model. Computer simulations have helped that a lot since the days of sliderules, but no matter how well you simulate or build a model, you still need to prove it in flight or action.

You actually run into the same issues with full scale.a lot of early rockets simply cracked under the were of their own rocket. 1:1 thrust to weight isn't that hard to achieve. The Navy Pogo, and flying flapjack were prop jobs with greater than 1:1..

I've seen some modified aerobatic aircraft that could take off vertically due to the over sized engines well that is if you stood them on their tails.

But i get what your saying, and agree models are only so good as examples..at a certain point you have to go full scale, and you are dealing with new dynamics.( mostly to do with materials, and structural loads)which is why test pilots had such short careers back in the day.

 

[FallingPhoenix]

I guess the point I'm missing in this discussion is why any ship with anti-grav would want wings?

 

[wbnc]

I guess the point I'm missing in this discussion is why any ship with anti-grav would want wings?

my original idea was as a fallback method of making entry, and being able to glide to a soft landing if it lost power. Coupled with heat shielding, to give frontier ships and scouts an extra margin of safety.

Either that, or as a means of improved efficiency in atmospheric flight.

 

[phavoc]

I guess the point I'm missing in this discussion is why any ship with anti-grav would want wings?

my original idea was as a fallback method of making entry, and being able to glide to a soft landing if it lost power. Coupled with heat shielding, to give frontier ships and scouts an extra margin of safety.

Either that, or as a means of improved efficiency in atmospheric flight.

I think their mass (or weight in a gravity field) is going to be too great for the hull shape to offset the lifting capabilities. The Space Shuttle weighs 165,000lbs, or about 82 tons. Even a teeny Scout is (or should) mass much more. It has crystal iron hull at a minimum, it's able to take damage from enemy fire and still function, it has entire ROOMS inside of it. The shuttle can be torn apart by a .50cal machinegun while a scout wouldn't even know it's been touched.

Then we have the fusion reactor, the jump and maneuver drives. Granted you are in a 'falling' mode the whole time, and that will help generate some lift. But you'd need a great deal of lifting body space to provide any sort of lift for such a heavy object.

The shuttle is able to do what it does because the wings and tail and it's aero-surfaces allow it to do so - but only within a very narrow window of maneuvers. I'm not sure if they have ever simulated a stall to see if it would be possible for it to recover. And any lifting body / super streamlined spacecraft would also need control surfaces specifically for atmospheric controls, or else it would be unable to properly maneuver.

Still, since the original question is a valid one. Since you are only looking to answer the question 'can you design a spacecraft to crash land so the crew survives', that might be possible, though I still think that it's a question of not having enough lifting surface to support the mass of the spacecraft. I guess if it's just enough to walk away from the crash while the ship is a write-off... that does change things slightly.

There's a neat and plain-english site from the Smithsonian that helps explain aerodynamics. You can find it at: http://howthingsfly.si.edu/aerodynamics/factors-affecting-lift

 

[FallingPhoenix]

There's a neat and plain-english site from the Smithsonian that helps explain aerodynamics. You can find it at: http://howthingsfly.si.edu/aerodynamics/factors-affecting-lift

Nice. I've actually learned the most aerodynamics since I started trying to design effective airplanes in Kerbal Space Program. Well, and trying to figure out why my rocket kept flipping over after SRB separation.

 

[wbnc]

Aero dynamicsis a hobby of mine..I'm a serious aerophile...and former recreational pilot..curse you high fuel prices...

When I started this I looked up a few of the larger aircraft. There are several aircraft that are int eh starship size range. Anatovs, super-guppies etc...Not that I expect starships to have those flimsy wings or be able to maneuver like an f-18....although oddly enough several very heavy aircraft are noted for extreme ease of flight, and maneuverability...for their size.

what I imagine is a bit more compact, with lifting bodies, flying wing/deltas rather than conventional aircraft wings. with only the smallest starships having full wings, or any form of maneuverability beyond gliding like a well thrown brick..which is far superior to flying like a lawn dart.

I can see 100, 200, maybe 300 ton ships with some degree of sustainable, controllable flight..with decent glide slopes. With flight speeds in the high subsonic/transonic domain...any more than that and yu need some really tricky aerodynamics to maintain which is why I mentioned super streamlining as a separate thing.controlled flight.

 

[phavoc]

The issue is going to be weight. Lift is possible, but you can also mass more than the lift you get, thus you have none.

Starships have armor hull plating, thus they will mass much more than the shuttle at a mere 82 tons. Because they use antigravity they have no need to use lightweight materials.