ACN --PCN

2018年08月19日周

ACN --PCN 

67

Daily English Of Dispatcher  

ACN --PCN 

ACN 

01

ACN 

飞机等级号

Aircraft Classification Number 

The aircraft classification number (ACN) is a number expressing the relative effect of an aircraft on the runway pavement for a specified standard subgrade category, using a method defined by the International Civil Aviation Organization (ICAO).

航空器等级号是一个表达航空器相对于规定的标准路基类别跑道的相对影响，是ICAO用来定义的一种特别的方法。

It consists of a number on a continuous scale, ranging from 0 on the lower end and with no upper limit, that is computed between two pavement types (rigid or flexible), and the subgrade support strength category. ACN values for civil aircraft have been published in ICAO’s Aerodrome Design Manual and in FAA Circular 150/5335-5.

它包含了一个持续变化的数字，从0开始，上不封顶，它计算了两种路面类型（刚性或柔性）和路基支护强度类别之间的关系。

The ACN of an airplane is a function of not only its weight but also the design parameters of its landing gear such as the distances between the wheels of a multiple-wheel landing gear assembly.

飞机的ACN不仅关乎于飞机的重量，也与起落架的设计参数有关，例如多轮起落架组件的车轮之间的距离。

ACN values for selected aircraft have been calculated by the International Civil Aviation Organization (ICAO) using two computer programs, one for rigid pavements and the other for flexible pavements.

选定飞机的ACN值由ICAO计算，使用两种计算模式，一种是刚性道面，一种是柔性道面。

重心越靠后，ACN值越大,厂家在Airport Planning手册中一般按后重心给出ACN值。

When the center of gravity is moving to the back of the airplane, the greater the ACN value may have. The manufacturer usually gives the ACN value in the Airport Planning manual according to the aft-position center of gravity.

重心一定的情况下，ACN与飞机重量成线性关系。

When the center of gravity is constant, ACN is linearly related to the weight of the aircraft.

PCN 

02

PCN 

道面等级号

Pavement Classification Number

PCN reflects the load-bearing capacity of the pavement. The larger the PCN, the stronger the load-bearing capacity of the pavement and the heavier the aircraft is allowed to take off and 

land.

PCN反映了道面的承载能力，PCN越大道面承载能力越强、允许起落越重的飞机。 

The pavement classification number (PCN) is an International Civil Aviation Organization standard used in combination with the aircraft classification number (ACN) to indicate the strength of a runway, taxiway or airport apron (or ramp). 

PCN是ICAO标准，和ACN一起来表示跑道、滑行道、停机坪的强度。

This helps to ensure that the airport runway, taxiway, and apron (or ramp) are not subjected to excessive wear and tear, thus prolonging the usable life of the runway while promoting safe 

operations of the aircraft landing thereon.

这些标准用来保证机场跑道、滑行道、停机坪不会被过度磨损，延长跑道稳定使用的寿命，提高航空器落地安全性。

The PCN of a runway is generally fixed, but if the strength of the runway varies seasonally due to freezing and other conditions, it may have different PCN values in different seasons (freezing 

affects the strength of the soil foundation).

一条跑道的PCN，一般来说是固定的，但是如果道面强度受冰冻等条件影响而有季节性变化的话， 则可以在不同季节有不同的PCN值(冰冻影响土基强度)。    

跑道的PCN由修建部门提供，可以在机场细则中查到，表示方法如下:PCN 90/R/B/X/T

PCN后面数字代表了该跑道的等级号，它与道面厚度、道面材料(水泥、沥青等)有关。 

第2个字母可以是R或是F，R(RIGID)代表刚性道面(硬道面)一般为水泥铺面，F(FLEXIBLE)代表柔性道面(又称软道面)一般为沥青铺筑面。

The second part is a letter: either an R or an F, depending on whether the pavement itself is of a rigid (most typically concrete) or a flexible (most typically asphalt) design.

第3个字母可以是A、B、C、D之一，反映了道基的强度的大小。

The third part is another letter from A to D expressing the strength of what is underneath the pavement section, known as the subgrade. So a subgrade of A would be very strong, like concrete-stabilised clay. A subgrade of D would be very weak, like uncompacted soil.

第4个字母可以是W、X、Y、Z之一, 代表允许的轮胎压力，

The fourth part is either a letter, or a number with units expressing the maximum tire pressure that the pavement can support. In terms of letters, W is the highest, indicating that the pavement can support tires of any pressure. Concrete surfaces can support tire pressures greater than those of existing commercial aircraft and are therefore nearly always rated W. 

第5个字母是T、U之一, 表示评价手段。

The fifth and final part just describes how the first value was worked out, a T indicates technical evaluation, and a U indicates usage – a physical testing regime.

Relations

03

The ACN-PCN system of rating airport pavements is designated by the International Civil Aviation Organization (ICAO) as the only approved method for reporting strength.

ACN-PCN是ICAO制定的一种计算道面强度的方法，唯一批准用来报告强度的方法。

The ICAO system for civil airport pavements involves comparison of an airport’s pavement classification number (PCN) with an aircraft classification number (ACN).

这种方法包含ACN和PCN。

According to this worldwide ICAO standard, aircraft can safely operate on a pavement if their ACN is less than or equal to the pavement load bearing capacity or PCN. 

基于这种方法，ACN必须小于等于PCN。

An aircraft having an ACN equal to or less than the PCN can operate without weight restrictions on a pavement. The PCN is formally published in an Aeronautical Information Publication (AIP).

为了能长期、反复在跑道上起降而不损坏该跑道，要求ACN≤PCN。 

For rigid pavement, if the runway is used occasionally, the ACN could exceed PCN 5%.

对刚性道面, 若偶尔使用该跑道, 允许ACN超过PCN   5％。

For flexible pavement, if the runway is used occasionally, the ACN could exceed PCN 10%.

对柔性道面, 若偶尔使用该跑道, 允许ACN超过PCN 10％。

The number of overloading taking off and landing shall not exceed 5% of the total annual take-off and landing times.

超载起降次数不超过该道面年度总起降次数的5％。