1. Control Requirements

1. 1. Control Requirements • CH. 10 Aircraft Control • - An aircraft is free to move in the six different ways in Fig. 10.1. • These are known as the six degree of freedom, and several aspects of each degree may be needed to be controlled. For example, we need to be able not only to set the pitch angle, but also to control the rate at which the angle changes. We may even wish to be able to regulate its rate of acceleration, so there can be eighteen or more different aspects to control. • interaction or cross-coupling effects • 2. The Pilot’s Controls • 3. Indicating Instruments

7. 4. Yaw Control • On conventional aircraft, the yaw-control pedals are connected to a movable rudder, which is attached to the vertical stabilizer or fin, as illustrated in Fig. 10.4. • Operation of the rudder effectively produces a camber of the vertical stabilizer surface, and this hence generates a sideways force. Since the side force is applied well behind the center of gravity, it produces a yawing moment. • Yaw control is not used as the primary means of changing direction, except when maneuvering(=manoeuvring) on or very close to the ground. • 5. Coupling between Yaw and Roll • - As the aircraft yaws to the right, the left-hand wing will move slightly faster than the right-hand wing. The faster-moving left-hand wing will, therefore, generate more lift, and the aircraft will

8. 6. Pitch Control • tend to roll clockwise. • - anti-clockwise rolling moment • By deflecting the rear of the elevator upwards, the tail plane is given a negative camber, resulting in a downward (negative lift) force. As the tail is pulled down, the angle of attack of the wing is increased, so that the final result of up-elevator is to cause a nose-up pitching moment, and an increase in overall lift. • slab, all moving and all-flying tail surfaces • Canard surfaces • 7. Vee-Tail • 8. Roll Control

9. - Roll control has traditionally been provided by means of ailerons on the outboard section of the wings, as illustrated in Fig. 10.10. • The ailerons are operated differentially; that is one goes up as the other goes down. The difference in effective camber on the two wings causes a difference in lift, and hence, a rolling moment. • Roll control by spoilers ; • * Spoilers are small surfaces which are designed to spoil the flow over a wing and thus reduce its lift. They normally take the form of small hinged plates which, when deployed, project up into the flow on the top surface of the wing. • * Spoilers were originally used to as a means of producing drag to slow an aircraft down.

15. 승강타(Elevator)의 작동

16. 보조익(Aileron)의 작동

18. 방향타(Rudder)의 작동

34. 조종균형 (Balancing Controls) • 조종면은 적절히 균형이 되면 조종하기가 쉬우며, 조종면이 무거우면 조종하기가 어려우므로 조종면의 작동 운동의 무게를 감소 즉, 조종력을 감소시키는 방법으로 앞전 밸런스, 트림탭 등이 이용된다. • 앞전 밸런스 (Balance) • 밸런스가 없이 조종면을 조작하기에는 큰 조종력이 요구되는데, 그림과 같이 힌지 앞쪽 부분에 밸런스를 둠으로써, 힌지축을 중심으로 조종면과 반대로 움직여 상대적으로 조종면의 효율을 증가시켜 조종력 감소 효과를 가져올 수 있다. 밸런스와 조종면은 힌지 축을 중심으로 그 무게가 평형을 이루지 않을 경우, 플러터(flutter)와 같은 진동의 원인이 되기 때문에 힌지축을 중심으로 평형을 이루도록 납덩어리 등을 부착하여 평형을 맞춘다.

35. 그림 4-14 앞전 밸런스 (Balance) • 트림탭 (Trim Tab) • 조종력을 경감시키기 위한 다른 방법으로 트림탭(trim tab)이 사용된다. • 비행기의 기수를 올리기 위하여 트림탭을 그림 4-15와 같이 아래로 변위시키면 작은 트림탭의 조작만으로 트림탭의 변화된 캠버로 발생하는

36. 힘은 승강타를 들어올려 위로 변위시키고, 위로 변위된 승강타는 결국 비행기 미부를 아래로 내리려는 피칭모멘트를 발생시킨다. 대형 고속 여객기는 아주 큰 조종력이 요구되므로, 전기(electric)나 유압(hydraulic)을 이용한 유압실린더(hydraulic actuator), 전기서보(electric servo actuator) 등을 사용한다. 트림탶의 작동