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19

What you want is the roll constant $\text{T}_R$. This is basically one of the characteristics wich determines the equations of motion of an aircraft. It gives the slope of the roll speed increase over time with full aileron deflection and an ideally stiff wing, and equally the rate of decrease once the ailerons are set to neutral during a rolling maneuver. ...


19

This answer is specifically for a fixed-wing airplane, not a helicopter or multicopter, although some aspects of it will apply to them too. What is a turn? A turn is a curvature in the flight path. This means a turn is a form of acceleration. Specifically, a centripetal acceleration-- the flight path is being continually "bent" toward the center of the ...


18

The key thing missing in your interpretation is that the order is important. Applying the same roll, pitch and yaw angles in a different order will result in a different orientation (mathematically this is because rotation matrices do not commute). The correct order is: Yaw (for an airplane this is typically called the heading) Pitch Roll For any given ...


11

Your question is an essence a question about aerodynamic damping in the roll axis. As the aircraft rolls, the rolling motion increases the angle-of-attack of the descending wing and decreases the angle-of-attack of the rising wing, eventually causing the lift created by each wing to be equal despite the deflected ailerons. At this point roll torque is zero ...


10

Yes, that will work. If the entire wing tip pivots, it simply acts as an aileron that takes up the entire chord of the wing. Other alternatives to ailerons include: Weight shifting. If you can shift the aircraft's center of mass left and right a significant amount, thus will cause the aircraft to roll in the same direction. This is how hang gliders turn. ...


9

What are the exact meanings of roll, pitch and yaw? It depends somewhat on whether you are speaking from a pilot's point of view or from an engineer's point of view. Your reference to yaw, pitch, and roll ANGLES is indicates you are looking at the situation from an engineering point of view. A pilot would tend to think more in terms of yaw, pitch, and ...


9

Think about the airplane as a body you want to control. That object has 6 degrees of freedom, including rolling. If you remove rolling you will not be able to control airplane's roll. Imagine a situation, when an small mass is over the wing and the airplane starts to roll and you are not able to compensate it. Saying that, the way to control yaw is to use ...


9

In addition to the use in turning, you need to realize that the atmosphere is not static. It's in constant motion, both horizontally and vertically. The vertical currents can be strong enough, and localized enough, to tilt one wing or the other*, thus causing an involuntary roll. If you don't have some means to counteract this induced roll, you now have a ...


8

When you turn by yawing you are skidding the airplane to point the nose to the side, to offset the trust vector to move the plane sideways as it's going forward. The rate of turn you can achieve this way is very low and there is a massive drag of being in a skid as you slither around like a car on ice with the fuselage side presented to the airstream. To ...


8

Roll, pitch, and yaw have two different meanings. They can refer to either Euler angles, which describe the attitude (orientation) of an aircraft, or ways that an aircraft can rotate. Euler angles The attitude of an aircraft can be described by three angles: heading, pitch, and bank angle (sometimes called roll angle). The heading $\psi$ (psi, sometimes ...


6

The attitude angles are explained in this wikipedia page, but it seems your confusion stems from the fact that they can present a singularity. Each set of unique Euler angles, outside of the gimbal lock state, represent a unique attitude. In the singularity state, however: The angles α, β and γ are uniquely determined except for the singular case that ...


5

A constant turn requires a constant centripetal force, i.e. perpendicular to the direction of motion. This force has to be generated aerodynamically (unless rocket engines are used). An aerodynamically generated force is always accompanied by induced drag - even if the force is generated by the fuselage (due to sideslip) instead of a traditional airfoil. ...


4

Here's simple way to conceive it. An airplane turns by tilting the lift force from straight up to angled off to one side, and to do this, it has to bank. Imagine the SpaceX rocket hovering. If it wants to move sideways, it tilts its thrust line off vertical. With the thrust line now pointed at, say, 11 O'clock instead of 12, some of the thrust is now ...


3

The minimum roll rate is documented in 14 CFR 23.157 (pre Amdt 64), which is used as an accepted means of compliance for the current 14 CFR 23.2135. As far as I know, there is no regulatory requirement on maximum roll rate. For large transport aircraft, the design target at maximum roll authority is typically around 20 deg/s to 30 deg/s. For example, A320 ...


3

One very important aspect is that roll, pitch, and yaw, relative to the aircraft (and the pilot that controls it) never change. As you progress as a pilot, using sky/ground as your reference is usually where we all start, indeed, as land walking folks, this is how we see our world. Practice flying model aircraft can help eliminate this mode of thought and ...


3

Depends on the speed: it costs very little extra energy to yaw a hovering helicopter. Yawed turn. A yawed turn increases sideslip angle $\beta$, creating a sideslip velocity which results in an aerodynamic force $Y = C_Y \cdot ½ \rho V^2 S $. Picture above is from measurements of an F-27 model with no flap deflection $\delta_f$, and shows an almost linear ...


3

Pitching up/down and yawing left/right would be adequate for a high wing dihedral design, were it not for the need for cross wind control. A high wing dihedral will make beautiful banked turns simply by pushing the rudder. The dihedral banks the plane away from the rudder induced slip. Great for indoors models. Unfortunately, in a full scale outdoors (...


2

Euler angles are relative to earth axes. Pitch, roll and yaw are relative to aircraft axes. Pitch means: nose up/down. Roll means: wingtip up/down. Yaw means: nose left/right. All from the pilots viewpoint. It is that simple. As confirmed by the Wikipedia article on Euler angles:, which first mentions proper Euler angles, then Tait-Brian angles pitch/roll/...


2

Think not about the rate of pitching but rather about the skyward or earthward curvature in the flight path (trajectory). This curvature is an acceleration, and requires a force to make it happen. G-load (i.e. load factor) is essentially just the aerodynamic force generated by the aircraft, divided by weight. In straight-and-level flight the G-load is +1. ...


2

The only1 instrument that directly indicates the bank angle is the attitude indicator, also (especially formerly) known as the "artificial horizon". As another answer has noted, many other instruments give indirect indications of bank angle, and by using them appropriately, it is quite possible to keep the wings level even with no direct indication of the ...


1

Many instruments can indicate roll. Here is a list in order of Primacy according to the Primary-Secondary Method of Instrument Flying: Heading Indicator Attitude Indicator Turn Coordinator Rate of Turn Indicator (when TC is absent) Inclinometer (actually only measures coordination) In the Control-Performance Method of Instrument Flying, and what most ...


1

If a plane is moving e.g. north and one wants it to be moving northeast, one must apply an eastward force to the airplane. A plane has four kinds of forces acting upon it--thrust, drag (force parallel to motion), "lift" (force perpendicular to motion), and gravity. The direction of gravity can't be changed, and drag will be parallel to the direction the ...


1

This animation shows it better than most. The swash plate changes the plane of the rotor disc to change the plane of the lift vector. It's the same thing as an airplane turning by banking. When an airplane banks it imparts a lateral thrust component to the vertical lift component and it moves sideways, and because it's moving forward as it does so, it ...


1

I was taught in and flew single and twin Pipers, Beechcraft and Cesnas in the 1980's. All these aircraft had the Russian style FAI, although we referred to them as ground pointers. I'm now flying modern glass cockpits using Western (skypointer) FAI. Although I understand the logic in the Western instrument is better, personally I prefer the Russian style. 10,...


1

This answer will tackle the question from the perspective of "How might a pilot trained on the Western style of attitude indicator be confused by the Russian style of attitude indicator?" This should also shed some light on the reverse question. In both of the instruments shown in the question, there is no doubt that brown is showing above the left wingtip ...


1

Instinctively, I would say that if the right wing (seen from behind) goes down (...), it will be delayed compared to the left one You are correct. This answer is aimed at the case where the ailerons are centered, and the local airmass is uniform, and the aircraft is rolling for some unknown reason (such as retained rotational inertia in the roll axis ...


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