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What's a simulation?

The real world—the world outside the screen—is incredibly complex.
Imagine an airplane flying through the air. There are multiple environmental factors affecting the plane: gravity, air density, wind shear, clouds, precipitation. Then there's the plane itself: it's shape, weight, wingspan, materials. So many factors affect how the plane will respond to its environment and how the environment will respond back.
A flight simulator attempts to re-create the experience of piloting an airplane. Modern flight simulators use computer programs and 3D computer graphics to simulate the land and sky outside the plane.
The view from the cockpit of a flight simulator as the plane approaches a runway. Image source: SuperJet International
Flight simulators can include a large amount of detail but at the end of the day, they are still only a simulation.
A simulation is an abstraction of an infinitely complex natural phenomena. It removes details that aren't necessary or are too difficult to simulate. The level of abstraction in a simulation depends on why we're creating it in the first place.
When the goal of a simulation is to help a pilot train to fly jumbo jets around the world, the simulation must represent the flying experience in the way that best helps them prepare for the real deal.
This Boeing 737 flight simulator includes a replica cockpit:
The cockpit is mounted on a platform that can move and rotate in all directions. The simulation of the plane's movement is an important detail for pilots-in-training, since it helps them deal with disorientation, motion sickness, and the effect of the motion on their ability to adjust the controls.
Animation of a Stewart platform. Image source: UtzOnBike
A simulation can also aid in the design of a new jumbo jet. In that case, the simulation must capture enough physical details to help engineers find flaws in the design.
Researchers developed this simulation of the air flow field around the landing gear of a Boeing 777:
That flow field is a big reason why an airplane landing makes so much noise. Aircraft designers can use that same simulation with new designs to see whether their design will decrease or increase the noise—and hopefully select a design that decreases the noise!
Simulations can be a source of entertainment. There are dozens of video games that simulate flight, with many of them revolving around combat or even a specific historical air battle. The video games may not be as accurate as the simulations used for pilot training, but they often include game mechanics that turn the simulation into a more game-like experience.
A screenshot from level 1 of the Flight Arcade game.
Thanks to the wealth of satellite imagery now available, flight simulations can include highly realistic scenery. The realism improves the educational experience for a pilot in training and increases the entertainment value for a gamer.
A screenshot from AeroFly FS. Image source: Blake Patterson
A simulation can recreate an aspect of our physical world, but at the same time, a simulation allows us to explore a phenomenon without the constraints of the real world. A pilot can crash without dying, a new plane can be tested out before a factory can make it, and a college student can get a taste of what it was like to fly a plane in World War I.
Let's explore more simulations and see how simulations helps us make advances in fields such as astronomy, physics, metereology, and medicine.
🙋🏽🙋🏻‍♀️🙋🏿‍♂️Do you have any questions about this topic? We'd love to answer—just ask in the questions area below!

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  • duskpin sapling style avatar for user nickolaus ___ branch
    i got no question
    (26 votes)
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  • blobby green style avatar for user Gideon
    Do we live in a simulated world?
    (9 votes)
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  • male robot johnny style avatar for user 🅹🅾🅷🅽🅽🆈
    Hi Everyone. I was also making a plane simulation/model.

    For this, I wanted maximum efficiency in flight without using an engine or fuel. I've made one that can fly for ~9.7 seconds with no fuel. I have a couple questions on how to make my glider have a longer flight time.

    For the first thing, I have a question about Yaw. With the simulation just going straight, and having no barriers, Yaw should not be needed. However, I tried the straight simulation with a Yaw amount at unstable, and the glider crashed to the ground. Since Yaw is just the turn, and no turn was required in the simulation, why did this occur?

    Secondly, I have a question about the Static Margin of the plane. It involves the horizontal stabilizer and the neutral point. I've looked at successful gliders, and the static margin was generally about -1. From the articles I've read, a plane is more likely to be stable if the static margin is about a positive 16 - 24. My personal best one has the MAX level of a Neutral Point, but it was only ~0.6. That is a BIG DIFFERENCE. Why does this occur? BTW, by MAX level of Neutral Point, I meant the best level. When I looked on the "Optimization" Tab, it showed it being all the way to the right, which means your Neutral Point amount is the best it can be for the specific glider.

    Also, this last question is more indirect, but keeping the plane <IN SPEC> (In specification) and without taking down the weight, how do I improve the Lift Efficiency to the Top? I know the increasing the Wing Span generally helps, but that adds weight. A little bit of Front Ballast helps too, but what can I do to make it better? Better yet, what shape is best for the lift efficiency?

    Thank you to any and all who answer this, -Johnny Unidas
    (2 votes)
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  • hopper cool style avatar for user Lucky
    What are the different variables, when considering the level of abstraction? I am thinking it depends on the simulation. But there must be a series of data sets that are common in simulation.
    (1 vote)
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  • duskpin ultimate style avatar for user Julicz
    is it possible to simulate the earth?
    (1 vote)
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