There are, to our knowledge, no internationally agreed safety standards for acceptable electromagnetic environments for aircraft. Given the potential risks which might be posed for aircraft operating within comparatively high electromagnetic fields during the approach to Longyearbyen airport, we endorse the approach taken by existing scientific radars of preventing any high power transmission when aircraft are, or are potentially, nearby.
We have entered into an agreement with the EISCAT organisation to share the existing safety infrastructure which combines a local aircraft detection radar with a manual over-ride switch located within the control tower of Longyearbyen airport. The provision of an aircraft detection system at the SPEAR radar and the control tower inhibit switch signal at the nearby EISCAT Svalbard Radar (ESR) will ensure that SPEAR transmissions would be prevented by either:
a) The local radar detection system indicating the presence of aircraft, or
b) The airport over-ride switch being operated by air traffic controllers.
This system would be implemented using established safety critical procedures which would ensure that both of these systems were operating before transmissions could occur. Effectively both systems would have to provide a "permission to transmit" status thus preventing transmission if either system failed for any reason.
This arrangement has the following advantages:
a) No additional switches would be required in the control tower and no additional procedures would be required by air traffic personnel minimising the likelihood of human error,
b) The local aircraft detection radar would provide an additional level of protection in the case of the over-ride switch in the control tower not being operated,
c) The combined system would only require a single safety audit.
The proposed system will prevent SPEAR transmitting when aircraft are present.