posted
Bernd is always complaining that kitbashes aren't correct and that scaling a ship up or down doesn't really work that way in real physics. I tried to find some real-life examples from aviation. When Bernd comes along, he'll correct my mistakes, so bear with me.
The P-38 Lightning was very fast for its day, and until the P-51 Mustang came along, it was the longest-ranged plane in the U.S. arsenal. It was so good they decided to try scaling it up.
The XP-58 Chain Lightning was an enlarged version of the P-38. As you can see, it wasn't quite as graceful-looking as the P-38. It wasn't so good as a long-range escort so they tried turning it into a ground attack plane. No good. Tried long range escort again, then cancelled the project.
The Lockheed VC-121 Constellation was a sort of "kitbash", since it's wing was scaled up from the P-38 (at least in shape). Unlike the "Chain Lightning", the Constellation was a successful and long-lived design.
The P-51 Mustang was another long-ranged design that was fairly successful. It was faster than the P-38 and had better range, too.
When the U.S. decided it needed a longer-ranged plane than even the P-51 to escort bombers all the way to Tokyo, they came up with the F-82B "Twin Mustang". This plane was equipped with 2 cockpits so one pilot could sleep while the other flew the mission. Later they slung a radar pod under the center section and turned it into a night fighter. The F-82 wasn't just 2 mustangs grafted together, but was a completely redesigned aircraft. The fuselages were actually quite a bit longer than the regular mustang.
The Convair B-36 was America's first purpose-built intercontinental bomber. It was designed in case England fell, and America found itself having to attack Germany or Japan by itself. It was a very-long-ranged aircraft and a few people thought it would be a good idea to design variants for other purposes.
The XC-99 was the first variant. At the time it was introduced, it was the largest cargo plane in the world. Unfortunately, it was so heavy it could only land at 2 airstrips in the world. It never went into production.
When the Strategic Air Command wanted a jet-propelled bomber, Convair built their YB-60 to compete against the Boeing B-52. The YB-60 was basically a B-36 with jet engines and swept wings. It was about 100 mph slower than the B-52 and wasn't selected for production.
As you can see, none of these planes looks exactly like the one it was derived from. Let the debate begin.
The First One
A lovely little thinker, but a bugger when he's pissed
Member # 35
posted
Wow. Absolutely fascinating. That Twin Mustang is weird. . .
------------------ "The next time the workplace seems especially hectic, remind yourself it could be worse: you could have two-dozen sharp-toothed creatures chewing on your nipples." - James Lileks
Scaling aircraft is useful to some degree, since the aerodynamic properties depend on the shape of the plane. This is why models can be taken into a wind tunnel to prove their ability to fly. The results can be transferred to larger planes, but it is crucial to take the increase of mass into account.
"As you can see, none of these planes looks exactly like the one it was derived from. Let the debate begin."
This is because not everything is scaled up. If two planes looked exactly the same but were supposed to have different sizes, you could easily demask one of them as a fake. For instance, if the pilot's seat is 2m wide . Or look at the engines which are larger relative to the small planes than to the large ones. Basically the same has to apply to starships. I don't deny that ships can be similar in shape (such as Galaxy and New Orleans), but even at the low screen resolution the differences must be visible.
BTW, I like the XC-99. I have never seen it before.
------------------ "Invaders from the fifth dimension!" - or: the canon proof that subspace is the same as hyperspace Ex Astris Scientia
posted
The Twin Mustang is a fascinating kitbash! If only the DS9TM ships had such reasonable descriptions. A few words about why the ship has been built in this fashion and would have been sufficient instead of the "hastily assembled" theory. If a ship is put together in a hurry, it has to be proven design with detailed specs and plans.
BTW: Anyone remember the "Flight of the Phoenix" (or something like this), a movie from the 50's where a two-engined plane crashes inmidst the Sahara and the passengers re-assemble it to a single-engined plane?
posted
First off, the B-36 (which originally only had 6 rear facing propellers, but 4 jet engines were added) was partially swing-winged, though not as much as the B-52 or YB-60.
Second, another showing of scaling in size. The X-33 is a working duplicate of what will soon become American's new Space Shuttle, the VentureStar. But, the X-33 is about 1/3rd the size of what the final VentureStar will be.
Also, the X-38, a 'lifting body' shuttle is another example of the tesbed being smaller then the real thing. The curent X-38 is too small to fit anyone inside, but can be flown. The final version of the X-38 will serve as the 'escape pod' for the ISS.
Yet another example. NASA's 'Dark Star', a pilotless, propeller driven recon plane. It is made of superlight materials, has I believe 8 propellers, and currently holds the record for the highest altitude reached by a propeller drive plane. The Dark Star is essentially a flying wing, but not like the B-2 Spirit, which has a large swept wing. The Dark Star has a large rectangular wing, extremely wide. NASA's final version of the Dark Star will nearly twice the width of the current version, and have nearly 20 propellers
Now, to the 24th century. They obviously scale. You can't tell me the Nova's nacelles are the same length as the Sovereigns. And they are nearly identical in design.
I think the word you were looking for was flexible. Swing-wing aircraft can adjust the amount of sweep, either on the ground or in flight.
Just wanted to point out that the P-51, arguably the greatest fighter of World War II, started out as a mediocre plane. The original, unsupercharged Allison V-12 was basically similar to the one used in the P-39 Aircobra. Performance fell off rapidly as altitude increased.
What saved the Mustang from becoming another so-so aircraft was the British performing a little kitbash of their own. Substituting the Merlin engine from the Spitfire (a much smaller, shorter-ranged aircraft) transformed the Mustang from a decent plane into a rip-snortin' butt-kickin' seriously lethal fighter, on a performance par with the best planes the Germans or the Japanese could field at the time.
Visual differences between the Allison-powered and Merlin-powered versions were few. The Allison had a small air intake just above the propeller that the merlin-powered plane didn't, and though I'm sure the nose profile was fairly similar, I imagine the placement of the crankshaft (and thus the thrustline) was different in each plane.
--Baloo
If Bernd (or someone else) would oblige, I think there are many other examples of kitbashed and re-scaled planes we could examine.
posted
Ah. I'll concede that point, thought I'll point out that the training edge of the wing was unswept. By that criterion, the DC-3 was a swept-wing design.
I don't think the wing sweep was driven by any aerodynamic consideration, but by the fact that they wanted the wing tapered (providing certain handling characteristics I forget now) and had to keep the trailing edge straight to avoid interference with those "butter paddle" props.
My original observation was that the B-52's wings were quite flexible. Boeing realized the plane would have to be heavily overbuilt (and just plain heavy) if they were to avoid wing flex. They brainstormed and decided that, rather than try to design out any flex, they would design the wing to flex in such a way that it did not cause the problems usually associated with wing flex. An added benefit would be that the flexible wings would absorb some of the aerodynamic shock when riding through turbulent air. The original design allowed the wings to flex 32 feet (~10 meters) up and 17 feet (~5 meters) down. In flight, the wings are relatively straight, but flex up and down as the aerodynamic load changes.
The First One
A lovely little thinker, but a bugger when he's pissed
Member # 35
posted
Plus there are fuel tanks in the wings, that when filled give the wings a noticeable droop, isn't that correct?
------------------ "The next time the workplace seems especially hectic, remind yourself it could be worse: you could have two-dozen sharp-toothed creatures chewing on your nipples." - James Lileks
posted
The359: Actually the Dark Star is a Lockheed Martin/Boeing stealth recon UAV that has a single jet engine. It is not a prototype for anything. It was a part of the semi-classified Tier 3 project and they made 4 of them, but they project was cancelled after one of the prototypes crashed. I'm not quite sure what the thing you are talking about is. Maybe that NASA thing that is just one big giant flying rectangle of solar panels with propellers on the back.
I know I'm really picky.
------------------ A-"Dippidy Doo." Q-"What forms on your dippity early in the morning?"--Johnny Carson
posted
Dangit, my mistake. I was talking about the Centurion, not the Dark Star. The name Dark Star was in my head because I remember it being in Jane's ATF Gold CD-ROM...
Anyway, the Centurion's replacement has been planned to be much bigger then this version
posted
The best example I can think of is F-117 aircraft. The first one was the cute little model called the "hopeless diamond" (that what I remember)[actually the whole project went from a normal unclassified project to top secret compartmentized project that didn't exist because of it super low radar signiture]. Then there was the 1/3 full scale model (which had the same radar signiture). Then the FY-117 I believe and finally the F-117.
Wait didn't the B-52 had an aerodynamic problem that caused the wings to "flap" at one point.
The Mustang had a Merlin, I thought it was a Rolls-Royce, however I could be wrong. And yes I knew about the Allison.
Btw the British hated the P-38, however that likely had something to do that the Supercharger wasn't included with their version .
------------------ HMS White Star (your local friendly agent of Chaos and a d*mn lucky b*st*rd:-) )
The P-38 Lightning was very fast for its day, and until the P-51 Mustang came along, it was the longest-ranged plane in the U.S. arsenal. It was so good they decided to try scaling it up.
The XP-58 Chain Lightning was an enlarged version of the P-38. As you can see, it wasn't quite as graceful-looking as the P-38. It wasn't so good as a long-range escort so they tried turning it into a ground attack plane. No good. Tried long range escort again, then cancelled the project.
The Lockheed VC-121 Constellation was a sort of "kitbash", since it's wing was scaled up from the P-38 (at least in shape). Unlike the "Chain Lightning", the Constellation was a successful and long-lived design.
The P-51 Mustang was another long-ranged design that was fairly successful. It was faster than the P-38 and had better range, too.
When the U.S. decided it needed a longer-ranged plane than even the P-51 to escort bombers all the way to Tokyo, they came up with the F-82B "Twin Mustang". This plane was equipped with 2 cockpits so one pilot could sleep while the other flew the mission. Later they slung a radar pod under the center section and turned it into a night fighter. The F-82 wasn't just 2 mustangs grafted together, but was a completely redesigned aircraft. The fuselages were actually quite a bit longer than the regular mustang.
The Convair B-36 was America's first purpose-built intercontinental bomber. It was designed in case England fell, and America found itself having to attack Germany or Japan by itself. It was a very-long-ranged aircraft and a few people thought it would be a good idea to design variants for other purposes.
The XC-99 was the first variant. At the time it was introduced, it was the largest cargo plane in the world. Unfortunately, it was so heavy it could only land at 2 airstrips in the world. It never went into production.
When the Strategic Air Command wanted a jet-propelled bomber, Convair built their YB-60 to compete against the Boeing B-52. The YB-60 was basically a B-36 with jet engines and swept wings. It was about 100 mph slower than the B-52 and wasn't selected for production.
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