The wonder of the aeroplane?

Question

How do aeroplanes take off?
How do they manage to stay in the air?
How do they manage to climb & and fall?
Can an areoplane travel at any speed?

Answer 1

Bernoulli says that when we increase a fluid's velocity, its pressure must decrease if there is no energy added.

Lift is generated by the air being accelerated over the top of the wing which creates a low pressure area, which 'sucks' the wing up. The result of this accelerated airflow is a downwash behind the wing. The amount of lift varies with speed, so we can't fly below a certain speed or the wing won't produce enough lift.

Producing lift causes a lot of drag, so we need to overcome this drag with thrust from an engine. Propellers and jets produce thrust the same way, they take a mass of air and accelerate it rearward, creating low pressure in front and high pressure behind to push the aircraft forward.

To climb, you need more power from the engine, not more lift. Lift is actually less in a climb than it is when the plane is level. To descend, you use less power (and slightly less lift), or you can point the aircraft to the ground and dive.

Aircraft can't travel at any speed. High speed jets are limited by thermal heating due to friction at the high end and not being able to produce enough lift at the low end.

BTW for lift, the top airflow also reaches the trailing edge BEFORE the bottom airflow, not at the same time. The reason the airflow is accelerated has nothing to do with a curved top, flat bottom, or the Coanda effect (which explains why air follows a curved surface, but not why it accelerates). Modern aircraft use laminar flow airfoils which are almost symmetrical in cross section. Modern jets use supercritical airfoils that are curved on the bottom and relatively flat on top.

Answer 2

Wow, that's a hell of a big-*** question.

* Take off/lift. There are two basic theories on this first one, although they are somewhat contradicting. The first is the most popular and commonly believed. An aircaft wing is shaped like this

(draw imaginary line to connect left bottom, top right)

_______)

and the supposed theory is that air travels faster over the top of the wing as to under the wing itself. The faster travelling air leads to low pressure above the wing the lift effect that is produced. The second theory is extensively more complex (and is far more likely in my opinion), a good explanation for this can be found here http://jef.raskincenter.org/published/coanda_effect.html


* How do they manage to climb and fall. Well, this is simply due to controllable lift surfaces called flaps. If the wing normally looks like above, and then you wedge the back half up, this will force lift

\ \ <-----Air pushes this bit
\__\_________)

^
I
Pivots around this point.


This will cause lift.


* Can it travel at any speed. Well, no is the answer. A prop aircraft is slower than a jet. A prop may theoretically travel at speeds up to about 800knots, wheras a jet can travel up to 3000knots (roughly highest speeds yet), this relates directly to aerodynamics such as the shaping of the wing, and the strength of the engine. The plane also has to deal with disrupted airflow as it breaks the sound barrier (about 730kts).

Hope I helped. If there's something you don't get or I've not covered, mail me...

Answer 3

i'm a pilot & I honestly have by no skill had an come upon the two distant or close with a meteor. Neither have I ever heard of the different pilot experiencing a collision, or possibly an intensive to omit with a meteor. 1st of all meteors that penetrate into the decrease altitudes that maximum airplane fly in are relatively uncommon. maximum meteors will dissipate till now they get low adequate to hit an airplane. so which you components up questioning approximately that one.

Answer 4

...................... the answer above is right ............ except that air meet at the same time .................... it travels more and therefore faster ...... hence creates low pressure on top of the wing ................. which in turn lifts the aircraft .................. the idea was from Bernoulli's theorem ........................
.................. it can stay in the air as long as it has forward movement to creat lift ..................
............... every aircraft has the lowest speed .... called stalling speed it cannot go below .... without falling .............
................ the the maximum speed depends on the air speed traveling on top of its wing ............ it cannot go more than or close to speed of sound ............... as it will create more drag ....

Answer 5

its all due to the raindrop shaped wing.
Above the wing, the air travels longer distance, so when it meets with air below, its later. So, the air below pushes the wing up.
It goes straight and fast.