Research On Photometric Characteristics Of Lighted Visual Aid To Indicate Temporary Runway Closure

With the expending of contemporary aerodrome and the increasing number of runways, lighted visual aid to indicate temporary runway closure plays an increasingly important role in guaranteeing the airport security and preventing the pilot down the wrong track. Photometric characteristics of lighted visual aid are the important factors to influence that if the device could effective warning pilots. At present, the lighted visual aid's light configuration and color haven't been unified and the relationship between its visibility and RVR(Runway Visual Range) has no specific data as a reference. It seriously affected the pilot's judgment, may bring safety accidents. Therefore, in order to ensure the safe of the aerodrome operation, it is definitely need to quantify the reliability of the device warning role and give the reference data for optimal, such as the size and color. According to the above problem, this paper presents some practical solutions.Firstly, this paper studies the characteristics of human visual, analyzes the impact of the intensity, color and contrast on the human eye visual and gives a visual base to determine the photometric characteristics about light visual aid.Secondly, in order that the visibility calculation results about the light visual aid with more practical reference value, it studied the relationship between the advection fog and radiation fog's attenuation coefficient and the atmospheric visibility which using the Mie scattering of spherical particle's law with the research object of fog which is the key element to RVR and modified the Allard's law and Koschmieder's law with the atmospheric optical thickness which related to the wavelength. Absolute threshold value method is used to establish the relationship between the RVR and atmospheric visibility and atmospheric attenuation coefficient, provides a data basis for study the relationship with visibility of light visual aid and the RVR.Thirdly, specific to the size and configuration, light intensity, color about light visual aid to influence the visibility of it. Size and intensity distribution are given which combined with the human eye dynamic resolution angle and the safety of the flight to overshoot in accordance with the requirements of recognition, came up with the method to calculate the overall luminous intensity with virtual points, used the method of absolute threshold combined with modified formula and introduced the relationship between visible distance of three kinds of light visual aids with a red, yellow, white and RVR, and gives the optimum light source color, provides theory basis for the design of the light visual aid.Finally, designed the experiment and proves the reliability and validity of the method to calculate the overall luminous intensity with virtual points and the design of light visual aid's configuration, light intensity, color with light visual aid scaling model which is easy to test.