I'm simplifying here, but every introduction to flying shows us that the profile of a wing leads to lower pressure on the upper side of the wing, hence the wing and the plane attached to it will be pulled up.
How does that explain a plane flying inverted? If the explanation was right, the plane would pull itself towards earth.
Normally, an airfoil is optimized for best lift/drag (L/D) efficiency for a certain flight profile (usually a compromise). Since most of the time for most aircraft inverted flight is not an issue, you get an airfoil that is optimized for upright flight, and this is best achieved with asymmetric geometries.
However, depending on the angle of attack any airfoil can (and will) generate "negative" lift, only much less efficiently so, than for the optimized regime, resulting in increased drag.
The desired angle of attack for conventional aerodynamically controlled aircraft is maintained by the elevator. For symmetric airfoils commonly used for aerobatic planes, the performance for upright and inverted flight is quite similar. For 99% of all other airfoils inverted flight will work up to a certain point, depending on the available power, CG, the maximum lift and rudder forces availabe before stall. As a result, for some aircraft, a stable inverted flight cannot be maintained, while for others it could be (but with varying penalty to performance, stall speed etc). The aerodynamical possiblity of inverted flight is of course limited by structural and other considerations.
This relation between a wing's curvature and a pressure difference on both sides is often part of the 'equal transit time' explanation; air on the curved side has to traverse a longer distance in the same amount of time, therefore goes faster, which leads to a lower pressure. This explanation is very common and completely wrong.
In normal flight, pitching the nose up causes the aircraft to climb because the wings meet the air at a steeper angle; the lift increases. It makes sense that rotating the wings in the opposite direction decreases lift. In fact, point the nose down far enough and the wings will produce no lift at all. Beyond that, the generated lift becomes negative and the wings will start to pull the aircraft down.
During our hypothetical manoeuvre, our attitude has varied by about 10°. That's not exactly flying upside down yet, the curved side of the wings were on top the entire time. Whether or not the lift was pointing up as well, depended on the angle at which the wings meet the air, the angle of attack.
The same is true for inverted flight. If we find ourselves at an attitude where the wings are pulling us down, we raise the nose. At first, the downward lift will disappear and at higher angles of attack, start pointing up and grow larger. At sufficient airspeeds and angles of attack, we have enough lift to maintain altitude upside down.
So why do wings need to be curved at all? They don't. Flat wings also provide lift at non-zero angles of attack and are perfectly usable, but not very efficient. Properly shaped airfoils create more lift and less drag. To find out why, consult a more accurate explanation of how planes really fly.
I'm simplifying here, but every introduction to flying shows us that the profile of a wing leads to lower pressure on the upper side of the wing, hence the wing and the plane attached to it will be pulled up. All right. How does that explain a plane flying inverted? If the explanation was right, the plane would pull itself towards earth.
When I was learning for my license, one of the first diagrams I remember was about the wing profile. The air going around the wing and on the upper side it has to travel a longer way, thus generating lower pressure and bang, plane is flying. Same explanation already back at school. See my other question: if the theory was right, why can planes fly inverted? So here's the follow up: why is this wrong theory so popular and still part of books? Wouldn't it make sense to teach students how a wing really works? I mean just look at any RC plane meeting - you'll be amazed what weird designs
Recently I was checking in to a flight and was asked if I'd like a window or aisle seat as usual and choose a window seat. I was then told that there are no more window seats available but I could get an aisle seat without someone sitting next to me and then just take that window seat. The plane was an ATR-72 so the rows were 2+2 seats. I know about weight distribution to the front/back but I couldn't come up for a good reason to do this. What could be the reason for not giving me that apparently free window seat right away?
I thought the shape of the wing gave an airplane upward lift. How can it fly if it's upside down?
to taxi doesn't help slow the plane very much, and flaps do constitute a hazard in gusts. Besides, it is surprising how much a small pebble costs when it goes through a flap. Is he right...In As the Pro Flies, John R. Hoyt writes (pages 41-42): Suppose we have to land in high, gusty winds. That's what happened to Pilot Z, who once landed his plane during such conditions with his flaps down. After the wheels were on the runway he relaxed, never realizing that a plane is not landed until the switches are cut. Because he still had airspeed and because full flaps lowered
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This video shows a Hawker jet with the wing fluttering up and down like it's about to break. What can cause flutter like that? Can it actually cause a wing or stabilizer failure? How can flutter be prevented? What should be done if something like this happens?
To most non-U.S. pilots who have little or no experience flying in the U.S., the concept of a FBO is not very well understood. What exactly is a FBO and what are the services that it can provide? I've heard that they can refuel your plane, move it to a hangar, clean it, provide preflight planning facilities, etc. Is there a charge for these services (I guess so) and if so, what can be expected? I've also seen many airports with multiple FBOs. How does that work? All I know is that FBO stands for "Fixed Base Operator". This may seem like a very stupid question but in Europe
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Quoting from page 162 of the book "Fatal traps for helicopter pilots" by Greg Whyte: Hydraulic jack stall (servo transparency) in (AS-350) helicopter is an aerodynamic phenomenon can occur when the helicopter is flown outside it is normal flight envelope and subjected to positive maneuvering (g-loading). It results in uncommanded aft and right cyclic and down-collective motion accompanied by pitch up and right roll of the helicopter. My question: What is reason for uncommanded aft and right cyclic collective down pitch up and right roll?