我们要根据大型飞机模型的不同用途去选择不同的翼型。翼型很多，好几千种。但归纳起来，飞机的翼型大致分为三种。

We need to select different airfoils according to different uses of large aircraft models. There are many kinds of airfoils. But to sum up, there are roughly three types of aircraft airfoils.

一是平凸翼型，这种翼型的特点是升力大，尤其是低速飞行时。不过，阻力中庸，且不太适合倒飞。这种翼型主要应用在练习机和像真机上。二是双凸翼型。其中双凸对称翼型的特点是在有一定迎角下产生升力，零度迎角时不产生升力。飞机在正飞和到飞时的机头俯仰变化不大。

One is the planoconvex airfoil, which is characterized by high lift, especially at low speed. However, the resistance is moderate and is not suitable for inverted flight. This kind of airfoil is mainly used in training machines and video cameras. The second is the biconvex airfoil. The characteristic of the biconvex symmetric airfoil is that it produces lift at a certain angle of attack and does not produce lift at zero angle of attack. The nose pitch of the aircraft does not change much when it is flying and when it is arriving.

这种翼型主要应用在特技机上。三是凹凸翼型。这种翼型升力较大，尤其是在慢速时升力表现较其它翼型优异，但阻力也较大。这种翼型主要应用在滑翔机上和特种飞机上。另外，机翼的厚度也是有讲究的。同一个翼型，厚度大的低速升力大，不过阻力也较大。厚度小的低速升力小，不过阻力也较小。实际上就选用翼型而言，它是一个比较复杂、技术含量较高的问题。其基本确定思路是：根据飞行高度、翼弦、飞行速度等参数来确定该飞机所需的雷诺数，再根据相应的雷诺数和您的机型找出合适的翼型。还有，很多真飞机的翼型并不能直接用于模型飞机，等等。这个问题在这就不详述了。

This airfoil is mainly used in aerobatics. The third is concave and convex airfoil. The lift of this airfoil is large, especially at slow speed, which is superior to other airfoils, but the drag is also large. This airfoil is mainly used in gliders and special aircraft. In addition, the thickness of the wing is also exquisite. For the same airfoil, the lift at low speed with large thickness is large, but the drag is also large. The low-speed lift with small thickness is small, but the resistance is also small. In fact, the selection of airfoil is a relatively complex and technical problem. The basic idea is to determine the required Reynolds number of the aircraft according to the flight height, wing chord, flight speed and other parameters, and then find the appropriate airfoil according to the corresponding Reynolds number and your model. Also, many real aircraft airfoils cannot be directly used for model aircraft, and so on. This problem will not be detailed here.

机翼常见的形状又分为：矩形翼、后掠翼、三角翼和纺锤翼（椭圆翼）。

The common shapes of wings are divided into rectangular wing, swept wing, delta wing and spindle wing (oval wing).

矩形翼结构简单，制作容易，但是重量较大，适合于低速飞行。后掠翼从翼根到翼梢有渐变，结构复杂，制作也有一定难度。后掠的另一个作用是能在机翼安装角为0度时，产生上反1-2度的上反效果。

The rectangular wing is simple in structure and easy to make, but it is heavy and suitable for low speed flight. The swept wing has a gradual change from the wing root to the wing tip, and its structure is complex, so it is also difficult to make. Another function of the sweep back is to produce an up-reflection effect of 1-2 degrees when the wing installation angle is 0 degrees.

三角翼制作复杂，翼尖的攻角不好做准确，翼根受力大，根部要做特别加强。这种机翼主要用在高速飞机上。

The manufacturing of delta wing is complex, the attack angle of wing tip is not easy to be accurate, and the force on wing root is large, so the root should be specially strengthened. This kind of wing is mainly used in high-speed aircraft.

纺锤翼的受力比较均匀，制作难度也不小，这种机翼主要用在像真机上。翼梢的处理。

Spindle wings are uniformly stressed and difficult to make. This kind of wing is mainly used in video cameras. Treatment of wing tip.

由于机翼下面的压力大于机翼上面的压力，在翼梢处，从下到上就形成了涡流，这种涡流在翼梢处产生诱导阻力，使升力和发动机功率都会受到损失。为了减少翼梢涡流的影响，人们采取改变翼梢形状的办法来解决它。更多相关飞机模型的事项就来我们网站http://www.quanyimoxing.com咨询吧！

Since the pressure below the wing is greater than the pressure above the wing, vortex is formed at the wing tip from bottom to top. This vortex produces induced drag at the wing tip, causing loss of lift and engine power. In order to reduce the influence of wingtip vortex, people take the method of changing the shape of wingtip to solve it. For more matters related to aircraft model, please visit our website http://www.quanyimoxing.com Ask!