Why the FUCK is this thing angled? i can't for the life of me understand why the flow has to be curved

why the FUCK is this thing angled? i can't for the life of me understand why the flow has to be curved.

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Let's start with the fundamentals of aerodynamics.

Why are wings curved?

beguz benises are gurved xDDDD

it's a ducted system, ostensibly operating at usually supersonic velocities, why would flow deflection of that manner matter here? unless it's meant to "bias" thrust vector to provide additional lift at lower velocities without resorting to active control by just having the thing constantly tilted.

>unless it's meant to "bias" thrust vector to provide additional lift at lower velocities without resorting to active control by just having the thing constantly tilted
ding ding ding ding

Why not just put rear thrust vectoring nozzles?? This seems like anwaste of engineering effort.

>Instead of designing it to thrust efficiently in the desired direction for the consistent and simple flight plan of this low-maneuverability-requirement aircraft, why not design it to thrust in any direction?
Why not just add mass and complexity to an already-very-expensive SSTO?

For thrust-vectoring in vacuum, the plan is to pivot the whole engine. This is typical for rockets, where you don't have to worry about keeping an inlet pointed into the airflow (something very important at the high speeds SABRE is meant to work at).

>why

Because aerospace companies need to burn funds nonstop and a 1000% increase in cost for a 0.5% improvement in performance is perfectly fine when your clients are governmental.

Why a Curved nacelle? – the most frequently asked technical question. The answer is: the air intake on the front of the nacelle needs to point directly into the incoming airflow whereas SKYLON’s wings and body need to fly with an angle of incidence to create lift, so the intake points down by 7 degrees to account for this. The rocket thrust chambers in the back of nacelle need to point through the centre of mass of the vehicle so are angled down; again by 7 degrees but it is a coincidence the angle is the same.
space.stackexchange.com/questions/12545/why-is-the-sabre-engine-curved

So what's the biggest hold-up with this supreme meme machine?

economic realities

terrible

First proposed test flight 2025... Grim, just grim.

It ain't Lego brosef Jr.

Because the plane is built with a 7 degree angle of incidence, but at very high speeds the intakes need to point directly into the airflow. Simplest solution is to just curve the nacelles.

The SR-71 is the same way, just with a more subtle curve.

They dropped it?

>Why does the model have those curved nacelles?
>Well, Sir, Uh, it's a design feature!

It pushes the plane up

Ok i get that it has to be in the direction of flow. But why is that flow downward and not parallel with the fuselage?

Engine cooling is very complicated.

Because the plane flies with it's nose pitched up. It's not like a normal plane that levels out to cruise.

Can someone tell a brainlet why helium is involved in a jet engine? And why there's liquid oxygen and an air intake?

because the earth is curved dummy.

Incoming air gets compressed at high speeds and gets very hot. Trying to burn hot air will melt the engine. The liquid helium transfers heat from the incoming air stream into itself and dumps that heat into the cold liquid hydrogen fuel. The cold air can then be used to power the jet engine.

The air intake is for atmospheric flight, and lets the engine use oxygen from the air. As the vehicle accelerates it eventually goes so high and fast that the pre-cooler can't handle the temperature and the air is too thin anyway, so the engine switches to an internal liquid oxygen supply, closes the air intake, and now operates as a rocket.

Physics.Hydrolox has a very low density and deep cryo causes high dry mass of tanks compared with other propellants.It can't compete against TSTO reusable rockets and is a relic of the 90s fad of SSTO meme machines like X33

Wouldnt that cause upwards drag?

It can compete easily just by being 1/100th the cost of operating.

Hydrogen tanks and engines make it unlikely to happen.Also TSTO with reusable upper stages will come to market much sooner than mememachine gets off the ground.New Glenn is expending the upper stage only initially

If you mean the landing a rocket meme, realize that regulations would make that just as unlikely.

lol ? which it will just magically achieve by virtue of being an expensive and complicated meme engine?
With an expensive and complicated meme space plane?

Solved problem unlike memecraft

A plane can land anywhere. Rockets cant. Its that simple.

rockets need a runway 1/100 the size of a plane you nut
Needs far less airspace too, since its coming down vertically

It's following the shape of the earth that it's orbiting.

fpbp

That runway has more tape than your moms bdsm kit.

Planes can land safely without engines.

Rockets need one hiccup before turning into a moab above a city.

Face it - rockets are primitive and incredibly dangerous technology that has zero use beyond warmongering and some miniscule scientific applications.

At least the latter benefit humanity in some way though.

I think he's saying that planes are not safe and in fact require a lot of maintenance. meanwhile a rocket is a simple thing, it's just a tube with a v8 on the bottom brapping to -1/12rpm.

How do you think we get satellites into orbit? We use satellites everyday for so many things that benefit humanity, that i wouls hardly call a rocket useless.

You mean lift? That's kind of the idea.

The engines only run for like 15 minutes on the Skylon, it's ascending almost the entire time.

>If you mean the landing a rocket meme, realize that regulations would make that just as unlikely.
SpaceX is already doing it.

>A plane can land anywhere.
Skylon, like the shuttle, would barely work as a glider and needs an extremely large, specialized airstrip.

>It can compete easily just by being 1/100th the cost of operating.
You're still looking at the Skylon hype based on comparing it to the space shuttle, which was uneconomical even by comparison to expendable rockets, rather than to the Falcon 9 that's already flying or the BFR that will be flying long before Skylon might be.

Skylon has the potential to be somewhat more mass efficient than BFR at putting payloads into LEO. Unfortunately, because so much of that mass is of the chemical fuel with the highest specific energy, it would actually be less energy efficient than BFR: the propellant cost should be higher.

Using 67 tonnes of hydrogen at 142 MJ/kg to put 17 tonnes of payload in LEO, Skylon would use 560 MJ of fuel energy per kg of payload.
Using ~1000 tonnes of methane at 55.5 MJ/kig to put 150 tonnes of payload in LEO, BFR would use 370 MJ of fuel energy per kg of payload.

When you factor in other energy costs, Skylon gains back a little ground separating and chilling oxygen from the atmosphere, since it would use proportionally less, but loses far more when it comes to liquefying the fuel, which is pretty reasonable for methane, but crushingly expensive for deep-cryogenic hydrogen (requiring approximately as much energy as the fuel itself contains), which boils at a mere 20 degrees above absolute zero.

On top of that, BFR is the far more versatile design: by developing an efficient reusable 2-stage VTVL rocket, one gets a propellant depot, Earth-departure stage, lunar lander, and martian lander almost for free. Because of the aerodynamic simplicity, after initial development BFR can be scaled up or down much more easily.

wings are curved because the earth is curved.

flat partners BTFO.

It has to cool intake air to a ridiculously low temp in order to work

Bcause thats how dildo rockets work