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The methods or mechanisms used to control an aircraft's movement in roll, pitch, and yaw.

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1answer
64 views

Is a Sun driven balloon/parachute possible this way?

Is it possible to make a helium balloon with a clear side to create lift from the heat from the Sun entering a transparent side like a hybrid hot air/helium blimp? How would the direction of the ...
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3answers
124 views

Do cellphones have the technology to measure altitude through an App [on hold]

Do cellphones have the technology to measure altitude through an App as they do speed and GPS.
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0answers
25 views

What are stick position stability and stick force stability?

What are stick position stability and stick force stability? What are the difference between them? How will changing trim of an aircraft affect them?
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0answers
10 views

How to determine maximum loads on control surfaces for supersonic flight

I checked control surface sizing and actuator selection having some estimates, but are largely meant for subsonic flight adhering to FAR regulations which dictate the maximum loads and flight ...
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4answers
178 views

In general, how do aircraft handle differently in inverted flight versus in upright flight?

Inverted flight is flight with a roll angle between 90° and 270° (although it classically referred specifically to flight with a roll angle of 180° - i.e., upside-down). In what ways, in general, ...
5
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1answer
163 views

What sort of control mechanisms (i.e., PID controllers) do modern FBW aircraft use?

It's a well-established fact that aircraft like the Boeing 777, and all Airbus passenger aircraft that were designed after the A300, feature a digital fly-by-wire control system. Considering the ...
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0answers
57 views

Why do so many supersonic aircraft feature delta wings and elevons?

Commercial and military supersonic aircraft constantly favor the delta configuration if they exceed the sound barrier, and also tend to be tailess or twin tail. What is the reason behind such designs? ...
1
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1answer
112 views

Why does elevator dropdown occur in some loss-of-flight-controls accidents, but not others?

In some instances of an aircraft suffering a catastrophic failure of its primary flight controls, the loss of control force on the elevator allows said elevator to drop down under its own weight, ...
5
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1answer
122 views

Why do some Mach trimmers move the elevator?

A pop-up rod on a the FO's control column on a DC-9 that shows the Mach trim position. (YouTube) Regarding the title, I'm not sure if it's just some or all jetliners (I tried to research it). On the ...
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1answer
88 views

Why does an elevator deflection (step) result in a nonzero short-term-steady-state response in pitch rate?

I know from the simplified Short Period linearized equations (state space with Angle of Attack ($\alpha$) and Pitch Rate ($q$) as states) that the steady-state value of the pitch rate response to ...
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1answer
65 views

Does the FBW system of a passenger aircraft use differential thrust for yawing? [duplicate]

Are there situations where the fly-by-wire system of a commercial passenger aircraft will use differential thrust to yaw? Or is that even possible at all (i.e. do the necessary interfaces exist)? I ...
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1answer
95 views

Fly-by-wire vs hydraulic systems [closed]

So, the great old argument, flyer-by-wire systems vs conventional hydraulics. I was wondering which one was better and why. Which one is safer? Pros and cons in terms of safety? Basically, I just ...
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2answers
214 views

Were Airbus planes always fly-by-wire?

So, as most of you know, Airbus has adopted fly-by-wire (fbw) technology. Pretty much every single plane made by Airbus is a fbw plane. So I was wondering, before computers were everywhere, did Airbus ...
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1answer
88 views

Is aerodynamic flutter speed dependent?

Is it possible for control surface flutter to occur at low Reynolds and low speed? If yes,why don't Ultralights have counter weights or tail sting mass to immune the control surfaces against flutter ...
1
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1answer
125 views

What is the “A/B AUTO EXT” button for in a Falcon 7X?

What is the "A/B AUTO EXT" button in the overhead panel of the Dassault Falcon 7X? I see it's in the Flight Control section but I don't know what is its purpose. (sorry for low quality image)
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1answer
2k views

Is it safe to fly a glider when I can't move the stick fully left and right?

This past Saturday, I started training in a Schweizer 2-33A glider. When I got in the glider for the first time, I found that I couldn't move the control stick fully left and right, because my legs ...
20
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7answers
12k views

How much physical strength is required to control a Cessna 172?

I have heard a number of folks tell me that one needs a certain amount of physical strength to be able to control the Cessna 172. Is that true? I'm flying sims now, just wanted to know.
1
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1answer
116 views

Is the 737NG hydraulicly controlled or electronically controlled?

I know that the 737NG is not fly-by-wire, but are the control surfaces controlled with hydraulic systems that transfer the input from the pilot to the control surfaces via fluid (hydraulics), or is ...
5
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2answers
315 views

Do any aircraft use throttle steering during normal flight?

If the engine(s) on one side of a multiengine airplane are set to a higher throttle setting than those on the other side, the airplane (all else being equal) will yaw towards the lower-throttle side; ...
4
votes
1answer
312 views

Why is it not allowed to dispatch an Airbus A320 with an inoperative ELAC 2?

In the case of ELAC 2 failure, ELAC 1 will take over. However, it is not allowed to dispatch an Airbus A320 with an inoperative ELAC 2. Why is that?
4
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1answer
447 views

What are the consequences of attaching an unused extra engine under Boeing 747 wing?

It turns out Boeing 747 can carry an extra engine under its left wing in case there's need to transport an engine somewhere far away. The engine is attached between the body and the left inner engine ...
7
votes
1answer
771 views

Why do the A220 cockpit seats have a cutout?

Why do cockpit seats on the A220 have a cutout on the bottom cushion? The answers to Aircraft pilot's seats: what is the notch for? explain that these cutouts allow for easier maneuverability of the ...
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2answers
168 views

What is the average aerodynamic load on a control surface of a commuter-sized airplane?

I'm doing a study about aircraft hydraulic pump sizing. In order to do that, I need to know the size of a flight control actuator, then determine the maximum flow and pressure that the actuator needs. ...
3
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2answers
229 views

Does “pendulum effect” apply to hang gliders or any aircraft?

In discussion of aircraft roll stability in FAA paragraph on dihedral effect and in keel effect and in Why are high wing aircraft more stable the question of pendulum effect arises. This is usually ...
5
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1answer
257 views

How can a VTOL aircraft control yaw while hovering? [duplicate]

I watched this video of a F-35B performing a flight-hover-flight transition and was pretty impressed by the fact that it was able not only to control pitch and roll (which could be, I suppose, ...
2
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1answer
121 views

How did the controls work for variable-pitch props?

Variable-pitch propellers date way back to the 1930's and even earlier. I would like to know, what kind of controls they used? Some kind of lever or crank? How heavy were these controls? I'm thinking ...
3
votes
3answers
438 views

Can you disengage A320 autopilot with stick pressure?

I was recently reading that in most military jets, auto-pilot can disengaged without hitting the button, by applying 5lbs of pressure to sticks. Does this work in commercial airliners such as the ...
2
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2answers
86 views

How can larger wingspan decrease the strength of wingtip vortices?

In the last paragraph from the link below, it states that Vortex Strength is inversely proportional to Wingspan. Why is this? http://avstop.com/ac/flighttrainghandbook/wingtipvortices.html EDIT: ...
6
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1answer
864 views

How is a light plane's nose wheel straightened during retract?

Assuming a light aircraft has direct cable linkage to the rudders, during taking off in a very strong crosswind with the pilot correcting with hard rudder, what keeps the nose wheel from remaining off ...
0
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3answers
189 views

How do aerobatic aircraft land?

The aerobatic aircraft I've seen don't have any flaps or air-brakes, besides they're taildraggers so I guess they usually have to do stall landing or three point landing but I don't understand how the ...
2
votes
1answer
103 views

Could simple fly-by-wire controls be installed in a prototype as quickly as a mechanical system with an autopilot?

It seems that fly-by-wire systems can take longer to get certified as the testing requirements are much more extensive. A prototype aircraft wouldn't have to pass these tests. How much more time or ...
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4answers
4k views

In the early days of flight, were there any cockpit control schemes other than the modern one?

Back in the early days, what kind of control schemes were invented for aircraft, other than the modern one? (pedals to yaw, yoke to pitch and roll). I'm only interested in control schemes that can be ...
3
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2answers
256 views

What is the direction convention for Roll angle?

This page from Wikipedia says: A positive rolling motion lifts the left wing and lowers the right wing. Which means that if an aircraft has a roll of +20 degrees, it would bank towards the right. ...
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2answers
553 views

What is the difference between a vertical stabilizer and a rudder?

I saw two questions on locating these surfaces ahead of CG: Vertical Stabilizer and Rudder How are these the same or different control surfaces?
10
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4answers
3k views

Do modern aircraft require rudder input in order to perform a coordinated turn?

With today's state-of-the-art electronic systems in modern aircraft, do aircraft equipped with autopilot systems, still require pilot rudder input to keep a turn coordinated? For the context, I'm ...
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1answer
118 views

How do I calculate the lift force on an aileron?

How do I calculate the force of lift acting on an aileron with a deflection of 8° and a flight speed of 40km/h?
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3answers
3k views

Why do many light aircraft have a trim tab on one side of the elevator only?

Most light GA aircraft, like this C172, have pitch trim tabs on one side of the elevator only. Why not on both? Doesn't the asymmetry add inefficiency in the form of a slight rolling moment?
2
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2answers
225 views

What is a minimal step angle deflection for flight control surfaces?

If the flight control surfaces (ailerons, elevators, rudder) are controlled digitally by servo motors, yet disregarding the way how the input to the servo motors get generated (manually or autopilot), ...
2
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1answer
155 views

Is it a good thing that ailerons remain deflected and the stick is hard to move?

The aileron stick of my homebuilt ultralight is stiff (hard to move) and the aileron itself can remain in its deflection angle hands free, is that a good thing?
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2answers
197 views

If the Quadcopter is a MIMO Nonlinear System, How Can it be Controlled using PID? [closed]

I know that it is very common to control quadcopters using PID algorithms. I'm just wondering if it isn't a problem that the system is highly nonlinear as well as having multiple inputs and outputs. ...
1
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1answer
81 views

FAA Turbine engine FCU regulations

Does the FAA have any regulations governing the design of a turbine engine FCU? I'm being questioned about an older Beechcraft PT6A FCU - in particular, how can I guarantee that when the power ...
1
vote
1answer
43 views

Any script to plot multi axis FDR / flight-test data (such as the ones used in air crash investigation)?

I am looking for a script or tool to create flight test and/or FDR plots with several vertical axis, such as the ones used in aircraft accident investigations. Does anyone have any hint on a MATLAB ...
0
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1answer
192 views

How are the wing control surfaces configured for takeoff?

For regular aircraft (i.e. a typical airliner), how are the wings configured before or during takeoff? Are there any adjustments needed for climb?
1
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2answers
389 views

What happens at the wings when the yoke is pulled backwards?

What happens at the wings and vertical stabilizers when the yoke is pulled backwards or forward on typical airliners like the Boeing 747-800. Is it any different for smaller similarly shaped aircraft ...
30
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3answers
6k views

Has there ever been an aircraft with three sets of flight controls?

On every aircraft I know, there is either one set of flight controls if it is single-pilot operated, or two sets of flight controls allowing either the pilot or copilot full control. Has there ever ...
11
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1answer
329 views

If a pilot's plane suddenly and unintentionally becomes inverted, what is the pilot's best course of action?

If a plane was suddenly inverted through no action of the pilot, say wake turbulence from a much large plane (think 747 vs. Learjet), should the pilot first try to right the plane or get the nose ...
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2answers
364 views

Do turnbuckles twist the flight control wires?

When adjusting a turnbuckle on any flight control, we usually use a wrench and turn the hex shaped section of the rod end inserted into the turnbuckle barrel. That flight cable from the turnbuckle is ...
3
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6answers
714 views

Why did fly-by-wire systems take so long to implement?

The first commercial FBW airplane was the Airbus A320, which was introduced in the late 1980s. This system only worked after decades of research by American and European aerospace companies. If FBW ...
6
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1answer
330 views

Can the fly-by-wire system of a modern airliner handle an unstable condition?

According to this answer airliners/large passenger aircraft such as an A320 are designed such that they are longitudinally, statically stable under normal flying conditions. What if, for some reason, ...
3
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1answer
235 views

Can different airliners of the same type feel different to a pilot?

(There's a related question Do two of the same model of aircraft feel different to fly? already. But: It's not about airliners, and most of the answers concern other aircraft. Not one of the answers ...