Also if someone says increase engine power doesn’t that increase planes weight which means you need more engine power and it goes into a infinite loop
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Engines push(or sometimes pull) the plane forward through the air.
As such, the air moves over the wings.
[The shape of the wings provides lift if air is moving over the wings.
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Engine power can be surprisingly low. A small single engine aircraft that can fit 4 people(under certain conditions) very well may have less than 200hp.
Maintaining altitudes is relatively straight forward, engine keeps providing forward movement, air keeps moving over wings.
Planes don’t fly because of engines. That’s a rocket you’re thinking of.
Planes fly because they have wings. Those wings allow them to glide in the air. The engines are there to speed up the plane up to the point where it has enough forward momentum for the wings to start providing lift, and to keep pushing the plane towards its destination afterwards.
A plane can fly with all engines off the same way a paper plane can. It’ll just have to come down at some point, but planes are engineered to stay airborne for a very long amount of time with no engines in case of failure so that the pilot can land locate a safe airport to land in. As an example, a typical airliner can glide for 100 miles with no engines from cruising altitude. It moves forward by simply converting the potential energy it inherently has from flying so high up into kinetic energy.
Planes fly because the force with which they redirect air downwards is more than their weight. The engine of course needs to be powerful enough to overcome drag, or the plane can’t maintain speed. But if you’re fine with slowing down, then you don’t need an engine. You just have a glider.
>Also if someone says increase engine power doesn’t that increase planes weight which means you need more engine power and it goes into a infinite loop
So, two things.
One, that’s if you increase engine power by putting “more engine” on. But even very early on, engine power contributing to lift quickly outstripped their weight contribution compared to the weight of the plane they’re powering. So generally, more engine is more lift.
Now FUEL, that does have this problem. More range = more fuel. More fuel = more weight. More weight = more fuel consumption. More fuel consumption = less range. There’s certainly a balancing act required there, but less so than rockets. Rockets have it really bad.
Two, you can increase power by making the engine BETTER, for the same weight. Then you can choose whether you want more power for the same weight, or sane power for less weight.
Engines don’t directly create uppies; engines create forwards. Wings convert forwards into uppies. Wings can also convert forwards into downies, but this generally isn’t advisable unless flying inverted, at which point uppies are actually just negative downies.
The lift comes from the wings, not directly from the engines.
When a plane is still, there is air pressure surrounding it on all sides. There’s pressure pushing down on the wings, and there’s pressure pushing up on the wing. That cancels out since the air pressure above and below the wing are the same. The plane stays on the ground.
When the plane is moving, the shape of the wing causes the air pressure on top to drop far below the pressure on the bottom of the wing. Since the air pressure is greater on the underside of the wing, that pushes the plane up.
Increasing the engine’s power doesn’t always come with a massive increase in weight that offsets effects of having a more powerful engine.
Scientists studied birds and then tried to recreate flight themselves. Through years of experiments they figured out that certain shapes of wings generate lift at certain speeds. It’s evolved to being able to control a 70,000kg fully loaded plane by manipulating each surface of the plane. The rudder, ailerons, flaps, trim etc are all control surfaces that alter the airflow. The engines keep the plane at a minimum speed that allows the wings to generate lift to keep the plane airborne.
Planes have a stall angle and speed. When the plane reaches a certain angle, at a certain speed, it will suddenly lose lift and plummet to the ground like a boomerang. Modern planes have safety features that will try auto correct the plane before it stalls (loses lift).
Because of the power of jet engines, plane can travel at higher altitude where there is less air resistance. A jumbo jet flying at 2000 feet burns through fuel much faster then one flying at 35,000 feet.
Wings are stunningly more efficient than you might think. To address your question about engine power; the amount of upward force (lift) that a wing produces is proportional to the square of the plane’s current airspeed. Making engines more powerful does add weight, but if you look at any aircraft the size of the engines is much smaller than the plane overall. For a normal two-engine passenger aircraft it’s 5% or less.
That said, most aircraft could fly faster than they actually do. Wings are really effective, and we optimise for fuel efficiency rather than maximum airspeed (usually around Mach 0.7-0.8 or so, since aerodynamics get wacky as you approach Mach 1.) Private jets often much faster than this since, being owned by rich people, they care more about getting places fast than saving money on fuel.
Actual ELI5: Wings make more lift when going faster. Bigger engines mean going much faster, and engines are very light compared to all the people and fuel.
Source: I have a degree in this
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