When i put them down on flight simulator, they make the plane rise. How do they help in landing???|||try pulling the throttle to about 1600 rpm's ( if flying a single engine)before deploying flaps and ensure you are in the white arch on the Airspeed indicator. ballooning will not be as pronounced.
Short and simple, flaps are designed to increase the efficiency of the airfoil at low speeds.
When used properly, flaps increase the lifting efficiency of the wing and decrease stall speed. This allows you to fly at a reduced speed while maintaining sufficient control and lift for sustained flight.
The ability to fly at slows speeds is particularly important during the approach and landing phases. For example, an approach with full flaps permits you to fly at a fairly steep decent angle WITHOUT GAINING AIRSPEED, which allows the airplane to touch down at a slower speed. In addition, you can land nearer the approach end of the runway, even when there are obstacles along the approach path.
Note to the know-it-all non pilots, you can, and I do often ,land without even deploying flaps . Hell, the PA-12 I have the luck to occasionally fly does not even have them. a slip to a landing works just as well IMHO|||It is up to the pilot to decide if he needs flaps or not given the particular conditions under which he is landing or taking off. Flaps lower your stall speed by changing the curve of you wing. In a lot of cases the way they are rigged, they extend towards the back as they move down, this makes for increased wing area as well as increasing the curve of the wing. When you change your flap setting, you are in effect moving the centre of pressure on the wing and this will make your nose rise or fall. In my airplane, the nose drops, but I think it is more accurately to describe it as the nose stays where it is and the back of the airplane goes up, because it feels like that is what is happening. Conversely when you retract the flaps it feels like the airplane is hinged on the prop and the tail drops. I don't know if this answers your question, but it sure was fun trying to explain this.
pilot and 30 years as a military aircraft maintainer|||The flaps increase surface area on the wings, which allows the plane to fly slower, while creating sufficient lift for it to fly.
You will see jet fighters will have thin swept back wings with little surface area, the speed of these air crafts will generate enough lift for it to fly, as for a small two seater plane, the wings are large, and straight, which generates more lift at lower speeds because of more surface area.|||putting flaps down when landing decreases the airplane's stall speed (the speed at which the wings cannot generate lift any more) because it increases the surface area of the wing. This allows them to land at a slower speed and decrease the roll-out distance (the distance the plane travels after the wheels have touched the ground)|||they allow the plane to fly at a slower speed.
You notice that they increase lift. so you get the same amount of lift but at a lower airspeed.|||They let your plane ride lower! Nice to meet you.|||Flaps help to lift and slow the plane right before landing so as to land softer at a slower speed.|||It makes the plane fly much slower to have an easier landing|||There are different types of flaps for a number of aircraft.Each type increases drag. Your initial question reguarding landings and the use of flaps can be sumed up by saying a good landing is touchdown at the proper speed and the proper attitude.Not to over explain it,but simply put,flaps produce an increase in drag while also increaseing lift for about the first 20 degrees deflection.So now with an increase in lift,your approach speed can be lowered.After 20degrees or more of deflection more drag than lift is produced.Part 2 of your question.An aircraft seeks it's airspeed once all four forces have equalled.Lift vs weight,thrust vs drag.It's trimmed out.When you applied flaps and increased your lift,the center of lift moved forward raiseing the nose until reaching it's new lower airspeed needed to produce the same amount of lift for your aircraft's weight.Left alone, a balance is restored at that new lowered speed.|||Flaps *reduce* your angle of attack for a given speed. They let you fly slower with the nose down. In addition to the speed reduction, this helps a lot with visibility.
Flaps increase lift AND drag. A little flap extension mostly provides lift, but a lot (full flaps) mostly provides drag. That drag lets you make a steeper approach (again, at slow speed, with the nose pointed down instead of up).
Also, the increased lift reduce stall speed. So you have a greater margin of safety at slow speed.
You don't *need* any flaps. Flying airplanes without flaps requires a technique called a slip, where you bank the airplane as if in a turn, but use rudder to stop that turn. The result is that the airplane flys almost sideways, and the side of the airplane produces the drag that flaps otherwise would. Slips also help with visibility, because even though you have the nose up to slow down, you're not looking out the front - you're looking out the side.|||They help in lowering the stall speed and slowing the plane donwn.|||I have to come down on ALOPILOT's side here. He is correct. Think about it, kbilyak. What happens when you suddenly drop full flaps? You immediately balloon up and the nose goes down while you're climbing in the balloon. Your illustration of the chord line without and then with flaps is correct only if it were a static situation. Flight is extremely dynamic and I promise you that in actual flight, the angle of attack decreases. Ernest K. Gann used the technique to avoid taking out the Taj Mahal when he was lifting in an overloaded cargo plane one day. Were it not for the effects we're discussing, the Taj would not exist.|||Flaps increase lift and drag. That allows the plane to fly at a lower airspeed, making for safer landings and takeoffs.
Since they increase drag, they can make a takeoff roll harder. But if you accelerate down the runway and THEN lower your flaps, you can really jump in the air fast; that's a STOL technique.|||It is correct that flaps REDUCE the angle of attack for a given airspeed... think about it... flying say a regional jet at 150 kts. with flaps up would require lots of nose up pitch to stay level... if you deploy full flaps, you would be near level pitch to maintain level altitude... THEY WORK BY INCREASING THE AREA OF THE WING!!!... They are not designed to increase drag as that is counterproductive when you are flying... they do increase drag as a side effect of the increased wing area... they fold down to increase the upside down "U" shape made by an airfoil... this creates an area of even lower pressure under the wing resulting in increased lift...
ADDED IN RESPONSE TO KBILAYK'S COMMENT: THANK YOU kbilyak0鈥?for the thumbs down as well as being a smart ***... I dont usually take offense to things like this but you really pushed the wrong buttons... and I will explain why I am an ATP certified Regional Airline Pilot and you are not even a CFI... As you can see in my above answer, I said almost exactly what the first paragraph of your link says (http://www.erau.edu/er/newsmedia/article鈥?/a> The only difference is that I put "the upside down U shape" so that the average person could understand... rather than the wing curvature... As I said, it increases drag, but only as a side effect of increased wing size or as your text calls it, wing length... its the same idea, more low/high pressure means more lift...
Now as for the part you told me to read... You say it increases angle of attack... The text says that it increases angle of attack *for a given pitch attitude*... The part you did not add is very important... Flaps take away the need for angle of attack, thus they reduce it... if you need 5 degrees pitch up to maintain 5,000 ft at a given airspeed, you need angle of attack to maintain altitude... If you deploy flaps, as I stated above, you can fly level (or closer to it) in level flight and thus have less angle of attack... its not that complicated and is something that you as someone who will be teaching the pilots of tomorrow should know...
Even though the 10th paragraph proves me right, the 11th explains it better in my opinion, less thrust for level flight than high angle of attack level flight...
Sorry, the ATP, Regional Airline Pilot, and UND graduate wins this battle...|||They slow the aircraft for landing. If you push the yoke in as you apply flaps, you won't show a rise, but simply will slow for a smooth landing.|||Lowering flaps produces lift, wich is needed when most planes or jets land. They are flying so slow that without the extra lift provided by the flaps they wouldnt be able to controll the aircraft.|||so you can fly slower and have the sameammount of lift as normal flight.|||The purpose of landing flaps are to steepen the descent angle without increasing the airspeed.
The reason for the rise in altitude when deploying flaps is because you are going too fast or you are putting in too much flap at once.|||By putting the flaps down the wings will produce more lift releative to the airspeed at which the aircraft is moving resulting in a lower approach an landing speed and also a steeper angle of descent, for example an aircraft that land at about 100 mph would need 150 mph landing speed without flaps.|||On most aircraft flaps have multiple positions and multiple uses. These all involve some combination of lift and drag.
In fast low drag planes it can be exceedingly hard to slow down and decend without the application of approach flaps (usually 15 degrees). They are also useful in the process of stage cooling (sequential limited power reductions) in large piston engine management.
During the final approach phase additional flaps are added to both lower the stall speed and provide better control of the decent angle (match the VASI lights or the instrument glideslope). On short final full flaps are usually added to further reduce the stall speed and add drag to slow the plane in the roundout and shorten rollout.
Gusty winds usually suggest a higher speed touchdown and full flaps are not used.
On some planes the short field takeoff calls for approach flaps to get the plane in the air with shorter ground roll. Almost all jets use some flaps at takeoff.
On really low drag newer planes, like the Mooney, wing spoilers are used in addition to flaps. Spoilers "spoil" lift as well as adding drag. Almost all jets have spoilers which you can hear woosh as they are extended.
Turboprop and turbojet aircraft also have thrust reversers which are deployed in the rollout to shorten runway usage. These work by reversing the prop a bit in turboprops (beta range) and by deflecting the jet output thrust with paddles on jets.
The combination of all these devices is exceedingly important in helping to manage the landing (and maybe the takeoff) environment which are by far the most risky portions of any flight.|||Deploying flaps increases the angle of attack. It increases lift as well as induced drag which is a by-product of lift.
The chord line of an airfoil is defined as a straight line from the leading edge to the trailing edge. Angle of attack is defined as the angle between the chord line and the relative wind.
1. Draw a picture of an airfoil so that the chord line is parallel to the ground. (Chord line is always a straight line from leading edge to trailing edge).
2. Draw a line parallel to the ground which represents the "relative wind".
3. Right now the angle of attack is zero, because the chord line and relative wind are parallel to each other.
4. Now adjust the drawing of the airfoil so that it has flaps deployed.
5. Now draw a line from the leading edge to the trailing edge (definition of chord line).
6. Has the angle of attack increased or decreased? Looks like you guys are in a tough spot.
Hey ALOPILOT looks like you have some reading to do. Here you go. Enjoy.
http://www.erau.edu/er/newsmedia/article鈥?/a>
READ THE 10TH PARAGRAPH DOWN
"Extending the flaps also increases the angle of attack of the wing for a given pitch attitude. "
And I'm Glad I pissed you off ALOPILOT (FBO boy). I graduated from a real flight school. You are dismissed.
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