UKCAA CAP 437 Ed.8 December 2016, Amendment 01/2018 September 2018, now stipulates that a friction test will be required irrespective of whether there is a net fitted or not. In addition, a friction test is now valid for 12 months. If the friction test results show a reading of at least 0.1above the required readings, in all the required areas, the friction test will be valid for 24 months. UKCAA CAP 437 Chapter 3 Section 7 states:- "A review of helideck friction measurement techniques has concluded that the test method should involve a friction measuring device that:
- employs the braked wheel technique;
- is able to control the wetness of the deck during testing;
- includes electronic data collection, storage & processing;
- allows the whole deck surface to be covered to a resolution of not less than 1 square metre.
The minimum average surface friction value of 0.60mu should be achieved across the area inside the TD/PM, and on the TD/PM and H markings. (0.65 on a moving helideck). Outside the TD/PM the required reading average is now 0.50.
HC-A carries out friction testing using the Findlay Irvine Micro Grip Tester which is the only type that currently meets UKCAA CAP 437 requirements. This was adapted for use by the manufacturer Findlay Irvine in conjunction with the HCA.
Friction testing may be done as part of the overall inspection process, or as a stand-alone inspection where required.