如何群众性的航空模型运动得到蓬勃发展,运动水平迅速提高。那么，下文是由 大型航天模型厂家为大家提供的航空模型知识讲解，欢迎大家来看。

How to make the mass aviation model movement flourish and improve the sports level rapidly. Then, the following is an explanation of aviation model knowledge provided by large aerospace model manufacturers. Welcome to see it.

1、升力和阻力

1. Lift and drag

飞机和模型飞机之所以能飞起来，是因为机翼的升力克服了重力。机翼的升力是机翼上下空气压力差形成的。当模型在空中飞行时，机翼上表面的空气流速加快，压强减小;机翼下表面的空气流速减慢压强加大(伯努利定律)。这是造成机翼上下压力差的原因。

The reason why aircraft and model aircraft can fly is that the lift of wings overcomes gravity. The lift of the wing is caused by the difference between the upper and lower air pressure of the wing. When the model flies in the air, the air velocity on the upper surface of the wing increases and the pressure decreases; The air velocity on the lower surface of the wing slows down and the pressure increases (Bernoulli's law). This is the cause of the pressure difference between the upper and lower wings.

机翼上下流速变化的原因有两个：a、不对称的翼型;b、机翼和相对气流有迎角。翼型是机翼剖面的形状。机翼剖面多为不对称形，如下弧平直上弧向上弯曲(平凸型)和上下弧都向上弯曲(凹凸型)。对称翼型则须有一定的迎角才产生升力。

There are two reasons for the variation of the upper and lower velocity of the wing: a. asymmetric airfoil; b. The wing has an angle of attack with the relative airflow. An airfoil is the shape of an airfoil section. The airfoil profile is mostly asymmetric, with the following straight arcs curving upward (flat convex type) and the upper and lower arcs curving upward (concave convex type). Symmetrical airfoils must have a certain angle of attack to generate lift.

升力的大小主要取决于四个因素：a、升力与机翼面积成正比;b、升力和飞机速度的平方成正比。同样条件下，飞行速度越快升力越大;c、升力与翼型有关，通常不对称翼型机翼的升力较大;d、升力与迎角有关，小迎角时升力(系数)随迎角直线增长，到一定界限后迎角增大升力反而急速减小，这个分界叫临界迎角。

The lift force mainly depends on four factors: a. The lift force is proportional to the wing area; b. The lift is proportional to the square of the aircraft speed. Under the same conditions, the faster the flight speed, the greater the lift; c. The lift is related to the airfoil. Generally, the lift of an asymmetric airfoil wing is large; d. The lift is related to the angle of attack. When the angle of attack is small, the lift (coefficient) increases linearly with the angle of attack. When the angle of attack reaches a certain limit, the lift decreases rapidly when the angle of attack increases. This boundary is called the critical angle of attack.

机翼和水平尾翼除产生升力外也产生阻力，其他部件一般只产生阻力。

Wing and horizontal tail generate drag in addition to lift, and other components generally only generate drag.

2、平飞

2. Level flight

水平匀速直线飞行叫平飞。平飞是基本的飞行姿态。维持平飞的条件是：升力等于重力，拉力等于阻力。由于升力、阻力都和飞行速度有关，一架原来平飞中的模型如果增大了马力，拉力就会大于阻力使飞行速度加快。

Horizontal uniform straight flight is called level flight. Level flight is the basic flight attitude. The condition for maintaining level flight is that lift equals gravity and pull equals resistance. Since the lift and drag are related to the flight speed, if the horsepower of an original model in level flight is increased, the pull will be greater than the drag to speed up the flight.

飞行速度加快后，升力随之增大，升力大于重力模型将逐渐爬升。为了使模型在较大马力和飞行速度下仍保持平飞，就须相应减小迎角。反之，为了使模型在较小马力和速度条件下维持平飞，就须相应的加大迎角。所以操纵(调整)模型到平飞状态，实质上是发动机马力和飞行迎角的正确匹配。

When the flight speed is increased, the lift will increase, and the model will climb gradually when the lift is greater than the gravity. In order to make the model maintain level flight under higher horsepower and flight speed, the angle of attack must be reduced accordingly. On the contrary, in order to maintain level flight of the model at low horsepower and speed, it is necessary to increase the angle of attack accordingly. Therefore, the control (adjustment) of the model to level flight is essentially the correct match of engine horsepower and flight angle of attack.

3、爬升

3. Climb

前面提到模型平飞时如加大马力就转为爬升的情况。爬升轨迹与水平面形成的夹角叫爬升角。一定马力在一定爬升角条件下可能达到新的力平衡，模型进入稳定爬升状态(速度和爬角都保持不变)。稳定爬升的具体条件是：拉力等于阻力加重力向后的分力(F="X十Gsinθ);升力等于重力的另一分力(Y=GCosθ)。爬升时一部分重力由拉力负担，所以需要较大的拉力，升力的负担反而减少了。

As mentioned earlier, when the model is in level flight, if you increase the horsepower, it will turn to climb. The included angle formed by the climbing track and the horizontal plane is called the climbing angle. A certain horsepower may reach a new force balance under a certain climbing angle, and the model will enter a stable climbing state (speed and climbing angle remain unchanged). The specific conditions for stable climbing are: the tension is equal to the drag plus the backward component of gravity (F="X+Gsin θ); The lift is equal to another component of gravity (Y=GCos θ)。 When climbing, part of the gravity is borne by the tension, so a larger tension is required, and the lifting force is reduced.

和平飞相似，为了保持一定爬升角条件下的稳定爬升，也需要马力和迎角的恰当匹配。打破了这种匹配将不能保持稳定爬升。例如马力增大将引起速度增大，升力增大，使爬升角增大。如马力太大，将使爬升角不断增大，模型沿弧形轨迹爬升，这就是常见的拉翻现象。

Similar to peaceful flight, in order to maintain a stable climb at a certain angle of climb, proper matching of horsepower and angle of attack is also required. If this match is broken, you will not be able to maintain a stable climb. For example, the increase of horsepower will lead to the increase of speed, lift and climbing angle. If the horsepower is too large, the climbing angle will increase continuously, and the model will climb along the arc track, which is a common phenomenon of rollover.

4、滑翔

4. Gliding

滑翔是没有动力的飞行。滑翔时，模型的阻力由重力的分力平衡，所以滑翔只能沿斜线向下飞行。滑翔轨迹与水平面的夹角叫滑翔角。

Gliding is a flight without power. When gliding, the resistance of the model is balanced by the component of gravity, so gliding can only fly downward along an oblique line. The angle between the glide path and the horizontal plane is called glide angle.

稳定滑翔(滑翔角、滑翔速度均保持不变)的条件是：阻力等于重力的向前分力(X=GSinθ);升力等于重力的另一分力(Y=GCosθ)。

The condition for stable gliding (both gliding angle and gliding speed remain unchanged) is that the resistance is equal to the forward component of gravity (X=GSin θ); The lift is equal to another component of gravity (Y=GCos θ)。

滑翔角是滑翔性能的重要方面。滑翔角越小，在同一高度的滑翔距离越远。滑翔距离(L)与下降高度(h)的比值叫滑翔比(k)，滑翔比等于滑翔角的余切滑翔比，等于模型升力与阻力之比(升阻比)。

Gliding angle is an important aspect of gliding performance. The smaller the gliding angle, the farther the gliding distance at the same altitude. The ratio of the glide distance (L) to the descent height (h) is called the glide ratio (k). The glide ratio is equal to the cotangent glide ratio of the glide angle and the ratio of the model lift to the drag (lift drag ratio).

滑翔速度是滑翔性能的另一个重要方面。模型升力系数越大，滑翔速度越小;模型翼载荷越大，滑翔速度越大。调整某一架模型飞机时，主要用升降调整片和前后移动来改变机翼迎角以达到改变滑翔状态的目的。更多相关事项就来我们网站 //www.leshep.com咨询了解吧！

Gliding speed is another important aspect of gliding performance. The larger the lift coefficient of the model is, the smaller the gliding speed is; The higher the model wing load, the higher the gliding speed. When adjusting a certain model aircraft, the main purpose is to change the angle of attack of the wing by moving the lift adjustment piece and the center of gravity forward and backward to change the gliding state. Come to our website for more information //www.leshep.com Ask and understand!