Helideck Friction Survey (Regulation) C.1 Friction Gauge Performing a helideck tribometric measurement involves several factors, all of which must be considered: - Limit friction values ​​quoted in CAP 437 is related to the minimum threshold at which a helicopter will not skid when landing on the helideck. The test method will therefore result in friction values ​​that are representative of the 'real life' situation of a helicopter landing on the helideck. The equipment used for the wheeled test used a tire made of the same material as a helicopter tire. - Helicopters can land almost anywhere on the helideck and the right level of friction will exist wherever the helicopter's wheels touch. This requires instruments that use a continuous measurement technique and surveys that cover the entire surface of the helideck. - Human error and the effects of commercial pressure often arise as factors in accidents, so a measurement method that is less dependent on human input offers greater integrity. Therefore, devices that provide automated electronic data collection, storage and analysis are preferred. In addition, this also encourages instruments to use a continuous measurement technique and surveys that cover the entire surface of the helideck, which, together, reduce the chance of missing 'poor' areas of the deck vessel during testing. Continuous Friction Measuring Equipment (CFME) provides automated data collection, storage and processing facilities that should be used for helideck friction measurements. They allow for consistently controlled surface moisture change perception, representative surface friction measurements, and allow the entire helideck area to be easily surveyed in a reasonable time. The friction measurement procedure applies to the use of CFME. C.2 Survey Procedure - The floor needs to be dry. - Minimum resolution is 1m2. C.3 Preparation - Calibrate the instrument according to the manufacturer's instructions. - Remove the mesh on the helideck surface (if any). - Check the helideck surface, clean as required. - Mark the location ready for survey. C.4 Survey - The entire landing area is covered by parallel lines not greater than 1m and repeated with perpendicular runs as shown below.