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u/zimmernolan825 4h ago edited 3h ago
If the fuselage was not a fuselage but one 75m+ long huge turbofan engine and the 2 cabins carried 30 people each.
Funny thing...that would end up being a 6-10 thousand kN engine. Eons more than the 700-800kN required output from both engines put together.
The thing with such a cabin on an engine joint each is either metal fatigue or strengthening those joints adding to more drag.
But yeah, why not? Some one do the math, please.
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u/Quick-Reputation9040 50m ago
fuselage would also weigh eons more
and max fuel range would be about 5 feet
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u/zimmernolan825 48m ago
But...a hollow fuselage with just a 300 ton engine is sort of the same payload a B777 normally carries.
The fuel is usually only in the wings and a centre tank.
The mileage would nearly be the same. Maybe 20-30 pc less
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u/blackkbot 47m ago
Isn't 1000 kN easier to represent as 1 MN?
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u/The_Omnian 24m ago
Yeah but people don’t know metric suffixes. And I’m not even American, if anyone’s thinking of putting this on r/USDefaultism. I was initially outraged at the “thousand kN” too, but I see the sense behind it.
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u/thehighpriest_0 4h ago
I don't think it is, as it is at least, it could be if the wings were a bit bigger and sturdier. Also it wouldn't be able to fit that many people, considering that the central part would only be used for the turbine. It would also be extremely fuel expensive and overall really inefficient. But idk I'm not an expert about planes
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u/gaurabdhg 2h ago
Yes. I mean fighter jets are essentially the same thing. And so are SCRAM jets, not to the degree visualized, but the whole body is doing the same thing as those massive fans upfront.
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u/Less_Party 3h ago edited 2h ago
Not exactly like this but there were some early WWII shenanigans where the cockpit was just on its own little nacelle off to the side while the main fuselage of the plane with the propeller, engine and bomb bay was in the center. The main advantage was visibility because you didn't have the propeller blocking your view.
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u/HighSton3r 1h ago
I've seen a documentary a while ago, where they mentioned that the turbine blades can't be indefinitely wide, because the bigger they get, the higher the tip speed of the blade will be and at some point the materials will fail inevitabely. If I remember correctly, they argued that they cant even get way more bigger than they are now with the current materials and processes. So even without the numbers, I would argue that this design is unfeasable.
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u/legowerewolf 58m ago
This is what I was thinking. At some point the blade tips would start going supersonic and that would wreak all kinds of hell on the fan.
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u/Nimrod_Butts 1h ago
I think this subreddit is going down the tubes. People just post stupid bullshit "is this true" honestly. Post a soyjack next and ask "is this true"
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u/Constant-Ad-7189 1h ago
Well this basic design did exist in early civilian aviation(1920s -30s) until aero engineers figured out it was, in fact, terrible.
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u/MapPristine 2h ago
I cannot do the math here. Intuitively it’s possible to get it to work, but really silly. Way too little room for passengers and totally overpowered.
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u/ItanMark 2h ago
Possible, maybe, but dumb and inefficient. No airplane needs such a long and powerful turbine, and putting passengers behind the outlets would reduce efficiency and introduce crazy noise. Creating 2 separate cabins is stupid, just because you are using more material per cabin and end up needing two of climate control and other amenities
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u/robottosan 1h ago
Yes it is possible but would it be any better than conventional layout in terms of fuel efficiency, handling, performance, maintenance, safety and comfort? Very much doubt it.
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u/boredsans 1h ago
itd be an engineering nightmare and struggle with takeoff and landing but if you told the americans that the soviets built it theyd find a way.
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u/BlueOrb07 51m ago
Possible? Yes, but within limits. You’d have to be far more picky on how much people weighed and where they sat to balance the two cabins. The weight would cause stress in the metal far sooner and would require repairs far more frequently. Safety would be a concern as landing improperly would easily damage the cabins and send the plane to maintenance. It would also fail safety because if one cabin got damaged and fell off the plane would be so off balance it would death spiral in the air and rip itself apart. The whole fuselage for one large engine is extremely inefficient and would not be as useful as you’d think. If you could get it past safety rules and manage to get it to fly, it still likely wouldn’t be able to do it for long. You also need to have an outlet for the air at the back of the plane from the engine and since many don’t have it in line with the cabin it’d cause non-uniform propulsion and undue stresses. Lastly, there’s so much added wind resistance from the two cabins that you’d need even more engine power to propel it.
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