a movable surface, usually near the trailing edge of a wing, that controls the roll of the airframe or effects maneuvers, as banks and the like. , The vertical flight of a helicopter is controlled by A. Not with a flying wing!!!!!! You can create differential elevon by having standard motion and giving a bit of up elevator!!!!!! If my JR allows differential in mix mode, it would only have the effect of pitching when you roll. Ailerons are used to control a plane’s longitudinal axis by altering the lift generated by each wing, with a pilot controlling the ailerons using a control wheel in the cockpit. Planes usually have two ailerons, one on each wing. This is another one of those videos tha. With this type of aileron, when pressure on the control stick or wheel is applied to one side, raising one of the ailerons, the leading edge of that aileron (which has an offset hinge) projects down into the airflow and creates drag. The way an airplane banks is by deflecting its ailerons. With increasing chord, the deflection range will become smaller, like ±15° for a 30% flap. This paper presents an assessment of flight dynamics and control under engine inoperative conditions at minimum control speed for a typical distributed propulsion aircraft employing differential thrust. The amount of rudder control required is greatest at low airspeeds, high angles of attack, and with large aileron deflections. The main questions are related to "tweaks" to the aileron system after a maiden it. RE: 707 Flight Controls #10801969. The aircraft control system controls the whole flight movement process. . (ˈeiləˌrɑn) noun. Ailerons connected to the rudder to reduce adverse yaw. Im trying to find out where the ideal control horn position is. Differential control on an aileron system means that A- one aileron on one wing travels further up than the aileron on the opposite wing to adjust for wash in and wash out. Oscillating glyph connected to the third rib segment of the morphing aileron [ 7 ]. Flaps. 40). From: Aircraft Design: A Systems Engineering Approach Mohammad Sadraey 792 pages September 2012, Hardcover Wiley Publications 12. The goal is changing the wings position for a coordinated turn - quickly with minimal drag. When the ailerons are deflected, the lift distribution is altered in such a way, that there is a net rolling. , produce an equilibrium state) for all required states in the flight envelope. Then how to recover from said spin. The aileron control surface is hinged to the wing frame; the links between the servo and the aileron hinge are also taken into account and their positions with respect to the l F wing station are defined as l a 1 and l a 2, see Fig. Ailerons are a primary flight control surface which control movement about the longitudinal axis of an aircraft. Change the aileron system in a Cub to increase the up travel and reduce the down travel. Aileron differential can help with this, but proper use of the rudder is more effective. When installing a castle nut, stat alignment with the cotter pin hole at the. 71- If the control stick of an aircraft with properly rigged flight controls is moved forward and to the right, the left aileron will move A- up and the elevator will move down. The AR636 in the Pitts can be configured for a two-servo aileron setup, which would then allow you to manage differential in the TX. What is differential control on an aileron system? With differential ailerons, one aileron is raised a greater. . , a corporation of Delaware. Joseph's College; Course Title RECREATION 253; Uploaded By LieutenantExploration3201. Differential Ailerons . Around or about the lateral axis and controlled by the ailerons. Modern radios should have the differential aileron function built in, where the each servo plugs into a separate channel. That means they have a lot of effective dihedral and essentially a flat-bottomed airfoil. Up to a point, increasing a wing’s AoA also generates greater lift. View full document. The up aileron produces extra parasite drag to compensate for the additional induced drag caused by the down aileron. However, with proper aileron placement and wing twist, an aileron can produce proverse or neutral yaw, eliminating the need for aileron-rudder mixing, differential aileron deflection, or Frise ailerons. Pitch control, this bit enables or disables pitch control output using the differential spoilers. differential aileron. Fig. a wall at the end of a roof with a single slope, as that of a church aisle. The size and planform of the ailerons are set by the roll-control power needed to meet flying qualities and maneuvering requirements. Description. Torque and directional control. Differential thrust can be used for directional control on distributed electric propulsion aircraft. , cruise with a new heading angle) with a desired rate or a specific duration. Though not entirely eliminating adverse yaw, the "differential type" aileron system raises one aileron a greater distance than the other aileron is lowered for a given movement of. The maximum useable deflection angle depends on the relative chord of the control surface. Independent multi-engine control for airplanes. 8269. >The FO SIDE controls the SPOILERS. It is also much less efficient at producing roll. Also, for a given control input, the servo has to work harder. Ailerons are used to control a plane’s longitudinal axis by altering the lift generated by each wing, with a pilot controlling the ailerons using a control wheel in the cockpit. , produce an equilibrium state) for all required states in the flight envelope. this creates excess drag in the direction to the "outside" of the turn, so aileron differential is used to. Prior to the use of ailerons. 4. Also, for a given control input, the servo has to work harder. measuring the angular setting of each wing at the rear spar with a bubble protractor. Differential ailerons function in the same manner as. Roll or bank is the aircraft’s movement about its longitudinal axis. 0. A. An elevon that is not part of the main wing, but instead is a separate tail surface, is a stabilator (but stabilators are also used. c ontrol activation. Ailerons are used in pairs to control the aircraft in roll (or movement around the aircraft's longitudinal axis ), which normally results in a change. RECREATION253 - During Inspection Of The Flight Control System Of An Airplane Equipped With. a part along the back edge of an aircraft's wing that can be moved to help the aircraft turn or…. The cable-operated control system of an all-metal aircraft, not incoporation a temperature compensating device, has been rigged to the correct tension in a heated hanger. Figure 7:Pulley system, Elevator ,aileron and rudder control The pulley system depends on the pilots muscles. Definition. The thing with differential is that the slower you fly and the closer to the stall the more you need. Forums; Magazine; Blogs; Classifieds; Places; More; Search; Sign Up | Log InNational Advisory Committee for Aeronautics, Technical Notes - A Flight Investigation of the Reduction of Aileron Operating Force by Means of Fixed Tabs and Differential Linkage, with Notes on Linkage DesignAerodynamics - Aileron Differential - a coordinated turn requires all 3 controls. 30 or 30%). If the Aileron Control System is jammed, force applied to the First Officer's. This greatly reduces. This block takes the input ω and produces the output θ. To return to wings level, the aileron on the right wing. . Select a Model Memory using Model SEL in the SYSTEM Menu. 1. 3° in flight. Aircraft Systems and Aviation – Concorde-1 ; Aircraft Maintenance Questions and Answers – Aircraft. 4, laterally/directionally motions are highly coupled, so the control of these two motions are discussed together. e. B- down and the elevator will move up. Figure 5 is a plan view of the majorpor p tion of the main plane of the amphibian, the structural members of the plane and the aileron control element being shown in dotted lines. What is differential aileron control and how does it reduce adverse yaw? 1) Differential Ailerons: One aileron is raised a greater distance than the other aileron is lowered. This producesA: Ailerons are used to create the motion of roll for an aircraft. If the aircraft is operated in very cold weather, the cable tension will. 0*aileron which is the usual way Aileron Differential is implemented if "aileron" is positive. With which system is differential control associated? (A). Example: Let's say I want to change the sub trim on the left wing ailerons [2]. With the control lock engaged, the maximum deflection of the nosewheel is restricted to 60° either side of center. This adverse yaw can also be prevented by the use of, Frise ailerons During inspection of the flight control system of an airplane equipped with differential-type aileron control, side to side movement of the control stick will cause A each aileron to have greater up travel (from the streamlined position) than down travel. Once the designer has defined these parameters, it’s time to pay attention to the design details of the ailerons and the control forces needed to fly the airplane. replaces the physical connection between pilot controls and rudder constitute the primary control system and are required to. Differential ailerons function in the same manner as symmetrical ailerons except that the upward deflecting aileron is displaced a greater distance than is the downward deflecting aileron. A hinged control surface on the trailing edge (rear side) of an airplane wing near the tip, the aileron moves up and down and controls the direction of a rolling turn. My thinking is that if you split the flaperon into 2 sections you might have more aileron control at lower speeds. Pages 40 This preview shows page 2 - 3 out of 40 pages. The differential control causes the up-moving aileron to move a greater distance than the down-moving aileron. This produces. Direct access to system setup from function menu - no need to. The amount of rudder control required is greatest at low airspeeds, high angles fo attack, and with large aileron deflections. This paper evaluates the flight quality of an aileron-free full-wing configuration UAV and proposes a highly robust attitude controller considering the typical control problems (i. To counter the effects of adverse yaw, you'll find a few different aileron designs commonly found on many airplanes. Flight Mode and SAFE functions can be put on channels 7 and 8 even though the RX is only 6 channels, and this lets you use. These consist of the flight control surfaces and the engine power management (unless you are flying a glider that is!). Three axes, three sets of controls (mostly) With a few exceptions, light aircraft flight control systems are very much alike, using hinged flaps along the trailing edge of each wing (you already know them as ailerons) to control the airplane around its roll axis. B. Without aileron differential, most airplanes require a certain amount of coordinated rudder to prevent—or at least minimize—adverse yaw. An example ofThe autopilot overpowers the trim and holds the control wheel where it is required for heading/track control. Though not entirely eliminating adverse yaw, the "differential type" aileron system raises one aileron a greater distance than the other aileron is lowered for a given movement of the control stick or wheel. Study with Quizlet and memorize flashcards containing terms like Primary Control Surfaces, Secondary Control Surfaces, Ailerons and more. An example of differential aileron deflection during initiation of left turn is: A) left aileron: 2° up Right aileron: 5° down. , Aileron Transfer Mechanism If the ailerons or spoilers are jammed, force applied to the Captain's and the First Officer's control wheels will identify which system, ailerons or spoilers, is usable and which. Contents hide. Scenario: Sat on the right wing. A Methodology for the Design of Active Fault Tolerant Control Systems. Wrote historian C. Differential control on an aileron system means that the up travel is more than the down travel. Induced drag is a by-product of the lift associated with the outside wing. 8. This produces. In one, the ailerons are jammed while deflected an equal amount in the normal, opposite directions. 2. ”. Excessive wear on both of the sides of a control cable pulley groove is evidence of. The control surface is considered aerodynamically unbalanced, flexible in torsion and with elastic axis close. 4, laterally/directionally motions are highly coupled, so the control of these two motions are discussed together. For example, in formation flight pilots constantly make small adjustments to stay in position. The ailerons become less effective whith the flaps down and not because of lower airspeed. The graphic below explores the. 7 Flight Control Computers Computer systems are now a common and essential part of many modern flight. I think the smarter way would be to alter the bellcrank geometry, but that would probably require two custom bellcranks. 19. F. This produces an increase in drag on the descending wing, which reduces adverse yaw. By making this control input, we are moving the lateral axis and rotating the airplane around the longitudinal axis. Slot-Lip Ailerons. In our example, raising your right aileron will cause the. Rudder Authority - The F-15 has three different hydro-mechanical rudder authorities: +/- 15 degrees of pilot input below 1. Tobin, Seattle, Wash. The pilot controls the forces of flight and the aircraft’s direction and attitude by means of flight controls. drag increases on the inner wing. C. Also having never been in a position to mix in rudder for coordinatedHi everyone, I am at the stage where I need to install the ailerons on my 1/4 scale ASK-18. Preview. Both explanations in the OP are correct to the overall phenomenon of adverse yaw. 3. 3. l F06 Why is it generally necessary to jack an. A sagging aileron or flap may be the cause of tremendous trim drag. ) Expired - Lifetime Application number US695963A Inventor Harvey C Mummert As discussed in Chap. Aileron and elevator definition, with listed variables, is shown below. Half of a wing with defined control surface is defined in Figure 2. August 31, 2020. An airplane has a pair of ailerons, controlled by servos, that move opposite of each other unless they are in the neutral (flat with the wing) position. Its fault detection can assist the aircraft PHM system in making decisions and completing the targeted maintenance, which is of great significance to improve the safety and reliability of the aircraft. Craig, The Futaba 351 is a single axis twin output gyro - so unless you are only one servo for both ailerons, this is the one you want to use. Was sat on the wing both ways and noticed something intersting about aileron movement. Wing flaps, leading edge devices, spoilers, and trim systems constitute the secondary control system and improve the performance characteristics of the airplane or relieve the pilot of excessive. An example of a moving earth axis system is an inertial navigation platform. With reference to differential aileron control. B. The purpose of spring tabs or servo tabs is to. 75. One purpose of the clutch provided between the engine and the helicopter transmission is to. Minimum recommended torque puls friction drag torque. The differential thrust control effort demands a maximum differential thrust of −3000 lbf (negative differential thrust means ), which is within the. However a rotation about one axis induces a usually unwanted rotation on the other one. Very often, repairs to a control surface require static rebalancing of the control surface. the up travel is more than the down travel B. If a pilot reports that an airplane flies left wing heavy, this condition may be. movement of the control wheel or control stick. 20 fully-proportional channels. With ailerons, things are a bit different because they are part of a lifting surface. Differential ailerons are ailerons which have been rigged such that the downgoing aileron deflects less than the upward-moving one, reducing adverse yaw. . . Aerodynamics - Aileron Differential - Gentlemen, I have a 1/3 scale Sopwith pup and I just set up the ailerons to where the ailerons move 2. Ailerons usually work in opposition: as the right aileron is deflected upward, the left is deflected downward, and vice versa. Questions and Answers - Aileron Differential - Can someone explain aileron differential to me? The way I understand it, there is less drag on the ailerons in the up position than there is in the down position. If using a modal basis for the system formulation (Borglund and Eller, 2013), as is common in aeroelastic applications, the mass matrix M equals the identity matrix and the system (10) is reduced to an ordinary linear eigenproblem. B. What is the significance about the mass balance/paddle?The ailerons and spoil-ers provide roll control, elevators pitch control, and rudder yaw control (Figure 12. aileron. The flaperons combine the function of: ailerons and flaps. Page 3- Differential ailerons question Modeling Science. . Each wing has a small flap on the rear, called an aileron. The rudder is typically used to counteract adverse yaw. 1 76 Answer B JSAT 1 45 AC65 15A When cables are rigged excessively tight it from AMT DEPART 425 at PATTS College of AeronauticsForums; Magazine; Blogs; Classifieds; Places; More; Search; Sign Up. InDifferential is required on very slow planes such as the Tiger Moth because the down-going aileron adds a lot of drag to that side, pulling the nose -out- of the turn. Inboard and outboard. This movement is referred to as "roll". Meanwhile, the left aileron will deflect downward, and that wing will generate more lift than the opposite wing. Increases force needed by. B. Mechanical Flight Control System. distance than the other aileron and is lowered for a given. roll) control of an aircraft; however, it also affects the directional control. 1 uses elevons as source for use with a flying wing, 0 uses ailerons as source for use with a traditional plane. With a glider of large span and high aspect ratio we need more upgoing aileron movement to counteract adverse yaw. 2. What you should look at is the relationship between the output arm of the servo, and the hinge line. these aircaft had absolutely no aerilon efect at stall, only rudder andPrecisely flying an airplane with an appreciable freeplay band is difficult, and with a decrease in precision comes an increase in pilot workload. Ailerons. +/- 30 degrees for ARI input with the stick. Ailerons are a primary flight control surface which control movement about the longitudinal axis of an aircraft. 19. . This force causes the. 1. Most airplane manufacturers use differential aileron control. Guess I should have said a little more in my last post. Learn more. e. This paper presents an aileron actuator fault diagnosis approach combining principal component analysis (PCA), grid search (GS), 10-fold cross validation. See Page 1This aileron control effort is very reasonable and achievable if the ailerons are assumed to have instantaneous response characteristics by neglecting the lag from actuators or hydraulic systems. This means that a control system designed for a maximum deflection of, say, 15° on the ground, may only deflect as much as 75% of that in flight. The following table shows the aileron deflection in a number of aircraft, which shows the differential aileron deflection ($\delta_{A}$ is the aileron deflection, in degrees). The normal convention for aileron differential is that increased aileron differential means that the upward going aileron has increased travel as compared to the downward moving aileron (the opposite of the sign convention in the quote). Aileron. In this system the aileron and rudder systems are interconnected, so that when the ailerons are deflected the rudder automatically moves to counter the adverse yaw. This part is easily rigged with a couple. 5 Mach number. primary flight controls. There are three sources of adverse yaw: Difference in induced-drag due to ailerons: down wing aileron reduces lift while the up wing aileron increases lift, which generates a difference in induced drag in each wing. The flap conforms to the shape of the upper surface of the wing when not in use and is designed reduce the flow of air through the slot. Study with Quizlet and memorize flashcards containing terms like In a hovering helicopter equipped with a tail rotor, directional control is maintained by, If a single-rotor helicopter is in forward horizontal flight, the angle of attack of the advancing blade is, The dihedral angle of a wing may be measured by placing a straightedge and level protractor on the and more. Ailerons connected to the rudder to reduce adverse yaw. The construction of the control surfaces is similar to that of the stabilizers; however, the movable surfaces usually are somewhat lighter in construction. A combination of aerodynamic balancing and tabs is generally used on ailerons with a mechanical control system. The cables can be manufactured from galvanized steel or stainless steel alloy, depending on the specs from the aircraft manufacturer. Does not change when in flight. each aileron to have a. The bank angle control system can be represented by a block with the transfer function G2(s) = 1. Control surfaces definition: AVL Control surfaces can be defined for part or for the whole span of the wing/horizontal tail, read carefully documentation. 30. This slide shows what happens when the pilot deflects the right aileron. Considered as a generalized fluid control surface, rudders, in particular, are shared between aircraft and watercraft. When one aileron is raised, the other is lowered a smaller amount. You need the programming cable for the RX to do this, though. *C- down and the elevator will move down. 1. Control roll about longitudinal axis. One aileron is mounted on the trailing edge of each wing—that is to say, the actual wing. In the most common form, aileron differential simply means that one will make the down-aileron movement less compared to the up-aileron movement. ailerons control____about the ____ axis. Control deals with the issue of whether the aerodynamic and propulsive controls are adequate to trim the vehicle (i. The relationship between wing planform, aileron placement, and lift distribution is studied. Adverse yaw. 2. Marcot3ch. Term. Rudder, similar tocontrol system aileron control differential differential aileron Prior art date 1932-02-16 Legal status (The legal status is an assumption and is not a legal conclusion. 4. Para 1 - confirming the question is a valid one and confirming it is actually the case. Yaw corrections are then done with aileron to rudder mix to keep the nose straight with the same wing rocking inputs. Servo power is effectively reduced when the total servo movement (termed travel volume by Futaba) is reduced. Aileron differential function should take into account the 4 wing servos when activated 06-24-2020,. Design Process: Aileron Types. On ailerons yes differential will help preventing adverse yaw. and the up-going aileron moves 30 mm and the down-going aileron moves 21 mm This means that • the down-going aileron moves 30% less than the up-going aileron ((30-21)/30 = 0. Control surface rigged such that the aileron moving up moves a greater distance than the aileron moving down. Adverse Yaw The reason why ailerons are sometimes set up this way is to counteract any adverse yaw when the airplane is in a banked turn. AKA - The "Flywheel". As the total servo throw is decreased, the proportion of play, or slop, in the control system is effectively increased. CONTROL Aileron 1. 10 Wing Types: Normal, Dual Aileron, Flaperon, 1 Aileron 1 Flap, 1 Aileron 2 Flap, 2 Aileron 1 Flap, 2 Aileron 2 Flap, Elevon A, Elevon B, 4 Aileron; 6 Tail Types: Normal, V-Tail A, V-Tail B, Dual Elevator, Dual Rudder, Dual Rudder/Elevator; Aileron, Flaperon, Elevon and V-Tail Differential ; Flap System with Elevator Compensation ; 5 Flight ModesAileron. Assembly and Rigging Practice Quiz #2. Therefore, in order to execute a good roll you have to have more throw in the up position than in the downDescription. The angle of incidence of an airplane at rest. One wing will go up, and the other will go down. Trim system will disengage or become inoperative if the primary flight control system fails. They are critical for the safe operation of the aircraft. Wing flaps, leading edge devices, spoilers, trim systems. Unlike ailerons, spoilers do not increase the lift of the upward-going wing. The slot-lip aileron [24, 25] is a lateral control device that regulates the flow of air through a slot made into the wing using a small flap (see Figure 25-28 ). When you roll right, the opposite happens. Definition of the aileron geometry. Once the designer has defined these parameters, it’s time to pay attention to the design details of the ailerons and the control forces needed to fly the airplane. Thus, the lateral and directional dynamics are frequently coupled. Despite the advances in aircraft guidance and control systems technology, Loss of Control remains as the main cause of the fatal accidents of large transport aircraft. cyclic pitch changes. This would necessitate a major alteration of which I have not been able to figure out a simple solution. The ailerons are the hinged part of. The tail drops. Ailerons designed to reduce adverse yaw. Movement around this axis is called ‘rolling’ or ‘banking’. The primary purpose of stall strips is to. 14. See Page 1 This aileron control effort is very reasonable and achievable if the ailerons are assumed to have instantaneous response characteristics by neglecting the lag from actuators or hydraulic systems. This preview shows page 5 - 10 out of 18 pages. A. we put in a step aileron input, we will get to 98% of the steady state roll rate. Adverse yaw. Option B. The down-going aileron is normally deflected through a greater angle than the up-going ailerons; hence, the differential drag they produce results in the yaw. The increased lift of the raised wing results in increased drag, which causes the airplane to yaw or swing toward the side or direction of the raised wing. Adverse yaw is the natural and undesirable tendency for an aircraft to yaw in the opposite direction of a roll. Differential control on an aileron system means that a pulling tool. The way an airplane banks is by deflecting its ailerons. First, the. 11ms frame rates with capable receivers. First, we look at single-degree-of-freedom, aileron rolls. $egingroup$ The problem with your suggestion is that when deflected upwards together, the ailerons would run out of wiggle room as differential ailerons. As discussed in Chap. , assignors to Boeing Airplane Company, Seattle, Wash. The bottom sector is the aileron control tab sector. The aileron control system preliminary. Differential control on an aileron system means that the up travel is more than the down travel. Ailerons are mounted on the outboard trailing edge of the wings. Note. Aileron differential simply means that the ailerons move more in one direction than the other, with the greater deflection being upwards. Adjust clevis to center transmitter trims, or reset computer trims. They are controlled by turning the yoke or stick left or right in the cockpit. The rig. Differential thrust can be used for directional control on distributed electric propulsion aircraft. One purpose of the clutch provided between the engine and the helicopter transmission is to. When the lift of an airfoil increases, the drag will. during inspection of the flight control system of an airplane equipped with differential-type aileron control, side-to-side movement of the control stick will. Ailerons are a primary flight control surface which control movement about the longitudinal axis of an aircraft. NOTE: The aileron throws shown for the top wing represents the differential created by using the aileron connecting rod. The down-going aileron is normally deflected through a greater angle than the up-going ailerons; hence, the differential drag they produce results in the yaw. uk. Differential ailerons function in the same manner as symmetrical. I have heard things like to help rolll straight to asssist in scale like turns etc. Ailerons are a primary flight control surface which control movement about the longitudinal axis of an aircraft. . The pilot changes the lift each wing produces to roll the aircraft in. Rigging and alignment checks should not be undertaken in the open; however, if this cannot be avoided, the aircraft should be positioned. The angle of incidence is that acute angle formed by. Normally, up-going aileron travels more than a downgoing aileron. manufacturers have engineered four systems: differential ailerons, frise-type ailerons, coupled ailerons and rudder, and flaperons. Differential control on an aileron system means that the up travel is more than the down travel. One aileron on one wing travels further up than the aileron on the opposite wing to adjust for wash-in and wash-out 45. Aierons, elevator (or stabilator), and rudder. The down travel is more than the up travel b. True. Ailerons. This means that ailerons can double as landing flaps without the flap travel having any influence on the aileron gyro function. 5 Mach number. The up travel is more than the down travel. The ailerons are attached to the outboard trailing edge of each wing and, when a manual or autopilot control input is made, move in opposite directions. Aileron differential makes sure the upgoing aileron (on the 'inside' of the turn) causes more drag than the downgoing one on the other wing, so the plane makes a nicely coordinated turn. A methodology consisting of an aerodynamic data acquisition module and a non-linear six. When the lift of an airfoil increases, the drag will. This increases the drag on the up aileron, and reduces it on the down aileron. The most basic flight control system design and operate with a collection of mechanical parts such as rods, cables, pulleys, and sometimes chains to transmit the forces of the flight deck controls to the control surfaces. g. Towing theIf it flies, I can crash it. the system. Three axes, three sets of controls (mostly) With a few exceptions, light aircraft flight control systems are very much alike, using hinged flaps along the trailing edge of each wing (you already know them as ailerons) to control the airplane around its roll axis. On faster planes with their more efficient control systems, differential as extreme as the TM is seldom seen. 3 on the two degree-of-freedom system. Note: For the learning process any Dual Rate settings must be disabled, to ensure that the maximum control surface travels are learned. This somewhat mathematical term aims to describe the reaction of an airplane to a given aileron input, for the moment ignoring the coupling effects (which we deal with later). Primary control systems. I find it is easier to make rate adjustments this way. The amount of rudder control required is greatest at low airspeeds, high angles fo attack, and with large aileron deflections.