Extensive Research and Development by the manufacturers of the SDR unit over an 18 month period resulted in the finished article, seen here fitted to the back of a standard HGV trailer:

A leading university aerodynamics department facilitated many of the early tests, including Wind Tunnel and computer model testing.

These computer simulations show airflow over a standard HGV truck and trailer unit BEFORE (above) and AFTER (below) the fitting of an SDR unit. The unit reduces aerodynamic drag, improves the stability of the trailer and helps to suppress the flume of spray generated at the back of the vehicle in wet weather - improving visibility both in the drivers’ rear view mirrors and for following vehicles.

The device was also tested in real conditions with a transport company over many thousands of kilometers. Following these tests, a reduction in fuel consumption of up to 6% was recorded. In the UK, validated fuel consumption savings following planned tests at the MIRA facility in Nuneaton are expected in the early summer of 2006.