Systems Interface Ltd

Systems Interface Ltd, known as SIL, is an air traffic management systems integrator based in Bordon, Hampshire, in the United Kingdom. Air traffic management, or ATM, is the set of systems that keep aircraft safe and moving in the sky and on the ground. SIL designs and delivers these systems for clients in more than 40 countries.

The company was set up in 1982 as a consulting engineering firm for UK airports. In 1999 it widened its work to full air traffic control capability. This covers turnkey solutions in communication, navigation, meteorology, control towers and design consulting. It says it has served civil and defence aviation authorities for four decades.

In March 2014, SIL became part of the Frequentis Group after Frequentis AG bought a controlling share. In March 2024, Frequentis AG bought the rest of the shares and now owns all of the company. SIL still trades as a systems design and integration company in the ATM sector.

SIL works on projects, and it works with manufacturers to supply complete custom solutions. Its services include system design, turnkey project delivery, installation and commissioning. This covers new installations and upgrades to existing systems. It also provides safety cases, training, maintenance, civil works and consulting.

A recent example is the Kabalega International Airport in Hoima, Uganda. SIL was chosen to design, supply, install and test an automated weather observation system, called an AWOS. As prime contractor, it manages the whole job. The system uses sensors for wind, pressure, temperature, visibility, cloud height and lightning.

The AWOS will give air traffic controllers automated weather reports and constant monitoring. It will produce METAR reports, which are standard airport weather messages. SIL and Campbell Scientific will give factory and on site training and a three year support program to the Uganda Civil Aviation Authority.

This work follows an earlier phase at the same airport. SIL supplied the instrument landing system, distance measuring equipment and Doppler VHF omnidirectional range, which are radio aids that guide aircraft. That phase was backed by UK Export Finance. The website explains the company's domains, news and contact details.