Questions tagged [flaps]
Surfaces that extend from the wings to increase lift, allowing flight at slower speeds (such as for takeoff and landing).
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How come deflected flaps cause a nose-up pitching moment in high-wing aircrafts and a nose-down pitching moment in low-wing aircraft?
I imagine that the increased downwash due to the new camber of a high-wing aircraft causes a down-force on the horizontal stabilizer which in turn causes a nose-up pitching moment. However, I read ...
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Role of Spoilers in Conjunction with Flaps A350
Upon observing the Airbus A350, I have noticed that both the outboard and a few of the inboard spoilers are deployed maybe three quarters of an inch when the flaps are fully extended. I assume this is ...
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How does a trailing edge flap move on an Airbus A320?
Airbus flaps move in flight direction [link]
I don't exactly understand how that works, do they move just 180 degrees (opposite direction) of the flight path or is it something else? And doesn't ...
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Disadvantages of the Fowler trailing edge flap?
I get that the trailing edge plain flap has disadvantages (like tendency to separate flow as I read on a question on here)
But what’s so bad with the fowler flap? Aren’t they like really efficient and ...
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Which one of these flaps is used on take off and land?
I’m really confused about which one of these flaps is used on take off and land?
I didn’t even know there were different types, I thought that the top configuration was the only used one today?
Also, ...
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Why are trailing edge flaps used for landing? [duplicate]
Why are flaps used when landing? Doesn’t a flap increase lift?
Edited: why are there so many different flaps on the back of a wing? Isn’t one just used when taking off and landing? Are the others ...
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Why is a level off required for flap retraction after a single engine failure?
In the Airbus A320, why do we need to level-off for flap-retraction after a single engine failure?
Even if we maintain a climb, the airspeed will still accelerate and be enough to retract the flaps ...
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Trailing edge flap disadvantages
What does ‘high local surface curvature’ mean with respect to trailing edge flaps?
I’ve been reading up on them, and that came up as one of their disadvantages?
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Is there any significance to the flap design on some Cessna citations?
In some business jets, I've noticed that the flaps seem to be split into sections. Here is one example on Cessna citation
As you can see, the flaps are split into three sections. The Embraer Phenom ...
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What is the additional planform area added to an A380 on take-off flaps setting (Flaps 1+F)
I would like to know how I can approximate the additional area added to wing on flaps 1+F:
Can someone use other dimensions they know of the A380 wing and approximate what this area would be, we can ...
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How does varying camber affects control over an aeroplane? [duplicate]
How does a trailing edge flap actually help an aeroplane?
It just changes camber but what does that exactly do that’s beneficial?
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What flaps are used for, if the aircraft has already landed? [duplicate]
When watching the below clip in the final approach sequence we can clearly hear setting flabs to 1, 2 and then to maximum.
At 12:05 into the clip, when fully landed ...
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Flaps type for Beech Bonanza V-35B
I'm writing a thesis on airplanes' flaps and I was analizing the flaps on the Beech Bonanza V-35B: on the book "The wind and beyond - Volume II" published by NASA on page 375 states that ...
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What happens to aerofoil downwash with Flaps extended vs retracted and how does it affect the Tail down force?
In my logic: Flaps extended will cause a greater Angle of Attack, to maintain Straight and Level Flight, AoA will be reduced, due to the increased "Surface", this allows to fly at lower ...
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How long does it take to complete a partial and full flap overspeed inspection?
I am trying to determine the cost of a flap overspeed inspection. Ignoring the cost of any parts. On average, how long does a flap overspeed inspection take? Or how long would a partial/full flap ...
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Can the flap on one wing be used to reduce a left turning tendency?
I fly a single engine Jabiru UL45 and it has a tendency to turn left during straight and level flight.
Is it possible, in order to reduce a "Heavy Wing" to slightly increase the degree of ...
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Is a plane stalled during landing rollout?
IMAGE SOURCE: https://pilotinstitute.com/wp-content/uploads/2022/01/Parts-of-a-Wing.jpg
As the lift dumpers are extended on landing they cause the air to move away from the wing. Also as the flaps are ...
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Why is flap retraction done in stages?
After takeoff and upon achieving positive climb, why is flap retraction done in stages?
For example, in the Airbus there are characteristic speeds after which flaps can be retracted (S and F speeds) ...
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Can flaps on Airbus/Boeing airliners be deployed at high speeds during cruise, still?
Brief Background of the Incident
Mayday Season 22 Features an Episode "Terror over Michigan" (Episode 6) based on the events of TWA Flight 841. The Episode revolves around a Boeing 727 ...
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How do GA aircraft flaps stay in place?
On most small GA aircraft such as the well-known Cessna 172P "Skyhawk", the flaps are electrically actuated. Now - how do they stay at the setting selected by the pilot after extension ? Is ...
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Is it possible to reduce the angle of fully extended flaps of an aircraft without affecting lift generated?
I think flaps are inspired from eagle feathers which increase the overall wing surface area and help provide the necessary lift at lower speeds. However, fully extended flaps hang lower and cause more ...
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Reasoning for an inboard flap- take off [duplicate]
so Ive been looking into airplane flaps, like the longer one for take off-
Is it correct to say that the only reason to have one is for take off, to make it take off easier?
And so when they take off, ...
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Elevator or Aileron?
I was just looking at an airplane take off, and when it was taking off, some flaps were facing down at the back of the main wings-
Are these Ailerons or elevators please? I did some research but the ...
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How can I calculate 'Max aircraft Load Factor' and 'Max aircraft Speed' when flaps are fully extended on a civil aircraft? [closed]
I am trying to calculate the critical loading conditions for Flaps (in order use them inside my Finite Element Analysis to, determine if the Flaps will be able to bear these critical loads) during the ...
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Does use of flaps or ailerons affect the aerodynamic forces distribution on the wing area before them?
Assume I want to use the flaps or ailerons at a specific altitude for some maneuevers on an aircraft. We know that the overall aerodynamic forces like lift and drag on an aircraft wing will change ...
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Why aren't takeoff flaps used all the way up to cruise altitude?
In general aviation aircraft such as Diamond star DA-40, flaps to take-off are used until 500ft AGL and speed before retracting flaps is Vy (best ROC speed)-67kts and after retracting flaps is 80kts.
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Is all the extra lift from flaps added upstream where the spars sit?
Flaps can significantly increase the lift for a wing, is all that extra lift added upstream where the spars sit? I ask this question because the flaps in airliners seem to be only connected by a few ...
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Does the A220-300 have krueger flaps or are all of its leading-edge highlift devices slats?
They look like slats to me, but I could be wrong. I'm asking because I know the 737, a very similar airplane, has inboard krueger flaps.
Also, what number of slats/krueger flaps does it have?
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What trailing edge flap design does the A350 use? Is it similar to the A380?
Both Airbuses have similar flap deployment based on some YouTube videos I have watched, just wondering if they both have the same flap design being "Single-Slotted Fowler Flaps".
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How many Krueger flaps does the 737-700 have?
How many Krueger flaps does the 737-700 have? It has inboard krueger flaps, but I'm trying to make out if it has one or two.
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What flap design does the A380 use? Is it Fowler flaps, slotted flaps or a combination?
I have looked at maintenance manuals, the Airbus website, and Wikipedia but still could not find a definite answer as to what trailing edge flaps the Airbus A380 uses.
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What are the approach speeds for each flap setting in a Cessna 152?
I am still trying to understand how the approach speeds for different flap speeds work. I cant find it in the handbook but I want to know the different approach speeds for the following flap settings:
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How can I design a slotted flap?
I have not been able to find satisfactory methods on design of slotted flaps, or flaps in general. Most of the answers are about eyeballing or experience. Can you guide me on what could be good ...
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Why does the Information Manual say "C172S - Flaps 10 (Preferred) for Normal Takeoff", when the models before S-model do not have this note?
Do Flaps 10 really do anything performance-wise other than reducing ground roll and distance over a 50-foot obstacle? If not worried about clearing an obstacle, does a Flaps UP-normal takeoff make ...
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Who manufactured the 737 MAX flap track fairings?
I can't seem to find the information online, would anyone of you know where / by who the flap track fairing for the B737 MAX is produced?
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Is pitch-flap coupling an aerodynamic effect or an intrinsic property of a delta 3 offset?
I am modelling a propeller, in particularly the equations of motion of the various pitch/lag/flap angles as the propeller is turning around. The blade includes a $\delta_3$ angle, which provides pitch-...
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Can flaps be used to perform rotation and flare?
TL; DR using flaps to directly control sink/climb rate near ground = simpler and faster response = easy to fly airplane?
Rotating is the pitch up during takeoff that causes the aircraft to leave the ...
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Is there a cockpit indication if the B737 flap load relief is not working properly?
On a 737, does the pilot get any cockpit indication that his Flap Load Relief is not working properly? Say for instance due to a Flap Lever Position Switch failure?
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Why does it feel like a plane stops in mid-air during approach?
At some stage while on approach to an airport in a commercial jet, it feels like the plane is almost coming to a complete stop in mid-air. Is this maybe as a result of the flaps engaging or the ...
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Is it safe to fly if the flaps won't retract on ground?
The Piper Archer (PA-28) i had this morning had issues returning flaps to normal after being fully extended ON THE GROUND. It required a non trivial amount of push on the air-frame itself to restore ...
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Is flap-asymmetry protection on airliners still active even on the ground?
On aircraft with flaps, a general certification requirement is that it must not be possible for the aircraft to suffer a loss of lateral control secondary to an asymmetric-flap condition. This ...
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Are overwing exits still useable if the flaps can’t be lowered?
Essentially all narrowbody airliners (except for the very smallest propliners), and many widebodies as well,1 are equipped with one or more overwing exits for use in an emergency evacuation; these ...
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Why is the DC-9-80 ("MD-80") prohibited from taking off with a flap setting between 13 and 15 degrees?
A bit of digging into the 7Z9363 accident investigation has brought up some interesting information regarding the DC-9-80 ("MD-80")'s flap system:
Flaps may be positioned in any of the six ...
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Why is there an altitude limitation on operating the slats/flaps on the A320?
As per the FCOM limitations chapter there is an altitude limitation of 20000 feet for operating the flaps/slats on the A320?
Why this specific altitude?
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What is the temperature of flap linkages during takeoff and landing in passenger and fighter aircraft? [closed]
During takeoff and landing, what is the temperature of flap linkages in passenger or fighter jet aircraft?
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How can the flap deflect to higher angles (than the wing) without experiencing loss of lift? [duplicate]
For a simple aircraft wing, assume the stall angle of attack of this wing is 16 degrees. Now, if I use the same airfoil as used in the wing for the flaps, I am able to deflect the flap at quite ...
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On large aircraft, why do flaperons not run the full length?
This is a 777 flaperon. It looks rather tiny, compared to the flap.
There have been air disasters where the airplane rolled uncontrollably for one reason or the other. It seems to me that a larger ...
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How do airplane designers determine flap deflection angles for flaps of various % wing chords?
How do airplane designers determine flap deflection angles for flap chords of various % wing chords? E.g. flap chord of 30%, 40% or 50% of wing chord.
I understand most flaps' chords are about 25% of ...
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Why not always take off with 10 degree flaps in a Cessna 172?
10 degree flaps increase our lift, reduce stall speed, reduce ground roll.
Seems like all advantages with no disadvantages.
So why does the Cessna 172 POH say normal take off is 0-10 degree flaps?
Why ...
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How can a designer deal with a strict requirement when designing an aircraft?
I'm working on designing an aircraft with some specific requirements (Vstall, Vmax, Ceiling, Payload, Range, RoC, Slanding/takeoff etc).
I'm following Anderson's and Raymer's ways (trying to find the ...
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