机场跑道磁偏角测量

磁偏角是机场建设中一个重要的测量数据，《民用机场勘测规范》（2008）要求磁偏角的测量精度优于0.1°，而目前教科书和有关测量规范并未给出相关方案。本文描述了某机场磁偏角施测的技术过程：根据当地磁偏角的日变特征，选取每日6：00—8：30及17：30—19：30进行观测，测距400 m；连续2天共测得29个观测数据，数据标准差为1.93'，与机场跑道外侧草坪内2个观测点的磁偏角相差3.93'，均小于0.1°，说明本次观测数据稳定可信，观测成果满足技术指标。

About measurements of magnetic declination of airport runway

The magnetic declination is an important data in the construction of the airport. The "civil airport survey specification (2008)" requires that the measuring precision of the magnetic declination is better than 0.1°, however the current textbooks and relevant specification fail to include introduction about the measurement process and requirements of the magnetic declination. This article describes a practical measuring project on certain airfield runway. Thought the process, a relatively stable period during which magnetic field changes slightly is 17:30 and 8:30, and a 400 m distance between observation point and landmark is suitable in the project. We get 29 pieces of measuring data and its standard deviation is 1.93'. The difference between the magnetic declination of the airfield runway and that in the lawn near the runway is 3.93'. They are both less than 0.1°, showing that the measuring result is stable and reliable and meets the technical requirement.