The system operates via a measuring wheel, mechanically geared to one of the rear main wheels of the base car.
Friction against the runway surface, in combination with the vertical load on the measuring wheel, creates forces on the measuring wheel mechanism that are constantly measured by the electronic sensor system. Signals from the sensor system are then processed in the SFTs computer system.
By processing these signals, the computer continuously calculates the friction coefficient, the friction number and the relation between the horizontal and vertical forces acting on the measuring wheel. The computer in the SFT is pre-programmed to measure and report runway friction in accordance with standards and regulations issued by ICAO, FAA, etc.
Result is then printed on paper in diagram form and figures. The data can also be transmitted to other receivers by means of radio links or GSM- phone.
Test and approvals:
- Approved by Swedish Civil Aviation Authority.
- Approved by Federal Aviation Administration (FAA).
- Approved and CE-certified (97/37/EG).
- EMC tested and approved (EMC/89/336/EEG).