An ever-increasing need for efficient and reliable airfield equipment has triggered both airport operators and their maintenance teams to develop their equipment to meet these changing requirements.

Constant current regulator technology is gradually moving away from thyrister driven circuits in favour of transistorised circuitry which reduces the power factor and helps to substantially reduce the harmonic distortion on the input waveform.

Airfield taxiway and guidance signs are also undergoing significant change in line with the low energy, high reliability demands of today’s airports. Originally illuminated either internally or externally by tungsten halogen lamps, and in some circumstances by cold cathode tubes, airfield signs manufacturers are now steadily moving toward the more efficient fluorescent tube.

This type of illumination not only gives a more even spread of light across the whole of the sign fascia, but is achievable with a limited number of tubes. Depending upon the type of tube used, life expectancy ranges from 10,000 hours to 50,000 hours, between 10 and 50 times longer than a standard tungsten halogen lamp, with some tubes operating at temperatures as low as -20°C.

Tungsten halogen lamps were used in the first taxiway guidance signs manufactured by Smith Airfield Equipment of Norway over 12 years ago and although the body of many of these signs is still in good condition, if airports are to improve reliability and energy efficiency an alternative solution to replacing all airfield signs must be used.

ATG airports have designed a conversion kit to overcome this problem and reduce the capital expenditure of the airport. Based upon the length of the sign, several gear plates/reflectors can be inserted into the sign, replacing all the existing lamps and reflectors. No specialist tools are required – the gear plates plug straight into one another and, once connected to the incoming supply, the conversion is complete. To achieve maximum performance the ground transformer will have to be reduced in size, and the CCR may have to be re-tapped depending on the number of signs on the circuit. This modification has been implemented on signs at Heathrow Airport and Manchester Airport for over 18 months.

As technology advances, we as manufactures have to keep pace and be in a position to supply this to the end users. This sign conversion kit is another example of ATG Airport’s ability to analyse the problem, develop the solution and deliver results.