# Laboratory Assessment of In-Pavement Airport Lamp's Luminous Intensity Distribution
## 2 Existing Methods and Devices for Airport Lamps Photometric Assessment  
The quality of airport lamps can be assessed stationary (using a light goniophotometer) [9; 10; 11], mobile (using illuminance measurement platform vehicles [7; 12; 13; 14; 15]), or with drones [16]. Mobile measurements allow us to obtain global information about lamps that may have limited efficiency. Such systems allow for the examination of both in-pavement and elevated lamps in the airport areas. The operating conditions of the device for assessing the quality of operation of in-pavement airport lamps are strictly dependent on the operation of the airport. The priority, apart from the obvious safety assurance, is the efficient conduct of air operations. Therefore, a device enabling the testing of in-pavement airport lamps on runways and taxiways must first and foremost quickly measure several hundred lamps. At a medium size airport, breaks allowing for measurements range from 5 to 15 min, depending on the time of day. Therefore, in order to carry out an accurate measurement of luminous intensity distribution, it would be necessary to close the airport for several days to carry out the measurements for every lamp. Therefore, for ongoing on-field control, devices are used to roughly assess the quality of in-pavement airport lamps. A thorough examination of luminous intensity is, therefore, possible in laboratory dark room conditions, where after unmounting the lamp, its angular characteristics can be checked. One of the well-known mobile systems is the patented DALMAS device (DeWiTec Airfield Light Mobile Analyzing System) manufactured by DeWiTec GmbH [13]. It is a single-axle trailer dedicated to measuring the intensity of lighting in in-pavement and edge airport lamps [12]. Another mobile system is PAC\({}^{2}\) V5, developed by FB Technology [14]. Like its predecessor, it is designed to test both in-pavement and elevated navigation lights. However, an important difference is that this device requires a special rack to be mounted in the front or back of the measuring car. The second device proposed conceptually by FB Technology is MARC ONE [15]. Its main assumption is an autonomous mobile robot that will independently perform a photometric inspection of navigation lighting and additionally will have the ability to check the correctness of screws that secure the in-pavement lamps. The device will be able to measure in night conditions only because the measuring matrix does not have its own darkroom. A similar device is proposed in [7], which is a mobile measurement platform to test the quality of operation in airport lamps. The device has been designed as a trailer that can be towed by an airport service car. Measurement fast speed illuminance sensors like those presented in [17] can be built as matrices placed on the bottom of the platform under a rubber cover. There are also known drone-based systems to test airport lamps [16]. The authors of this paper proposed a photometric method that uses a measurement matrix suspended from a drone, reducing dependence on airport infrastructure conditions. The instrument consists of two subsystems: the data acquisition unit and the master station, which communicate wirelessly. However, this system has many other limitations, such as inspecting at large intervals from flight operations and being dependent on weather conditions. There are also three solutions that allow stationary testing of navigation lighting lamps and for making measurements related to angular relationships with high accuracy. One of them can be used stationary under real-life conditions without disassembly of the lamp from its housing--PAC MATRIX [9] and the next two are intended for use in laboratories--PAC LAB II [10] and PTS-200 [11]. The first is the PAC MATRIX system, manufactured by FB Technology. It is a stationary matrix (array) intended for photometric measurements of airport lamps of various types [9].