1. The Why and How of Runway Friction Testing by Delia Harverson Findlay Irvine Ltd. Midlothian, Scotland and Thomas J. Yager NASA Langley Research Center Hampton, VA, USA Part 1: A Brief History

2. What were the first Continuous reading Friction Measuring Equipments [CFMEs ]? When were they introduced?

3. The first CFME was the Skiddometer designed in Sweden in the late 1950s

4. the second CFME designed by the UK Ministry of Defence in the early 1960s was the

5. 1962: a Canberra lands on a winter contaminated runway... Why were these early CFMEs developed?

6. … and comes safely to a stop The first CFMEs were developed mainly for testing in winter conditions

7. After the Skiddometer and the MuMeter came the Saab Friction Tester which was also originally designed to measure in winter conditions

8. Later CFMEs were designed as much for maintenance testing as for operational testing

9. ? Is it as important to measure runway friction in summer as in winter?YES! In rain, a runway with poor texture and rubber deposits can be just as slippery as a runway contaminated with ice and snow

10. An accident waiting to happen …

11. Are there more overrun accidents on wet runways or on runways contaminated with ice and snow? There are substantially more overrun accidents on wet runways Most of these accidents need never have happened

12. Nothing will guarantee that an overrun accident wont happen at your airport … … but regular use of an approved, well maintained CFME will make it less likely

13. Operational testing is carried out in natural conditions, in winter, in order to make immediate operational decisions. Maintenance testing is carried out in carefully controlled conditions, which include an exact amount of water put down in front of the measuring wheel, in order to make engineering decisions.

14. Should engineering decisions ever be made on the basis of operational testing?No! Natural conditions are much too variable to provide a proper basis for engineering decisions

15. How do we ensure that maintenance friction testing is consistent … … that the same results are obtained in Lima as in London Heathrow? … in Santa Cruz as in Singapore?

16. For this, the international community depends onICAO

17. Forget it! Before we get onto ICAOs role, two quick words about the lunch-box test …