U6 Estimation question 2015 #1

Calculate the maximum tension in the support cable. This time, here's an outline of what to do:
1. Use a pendulum formula to calculate the time period. Now you have the frequency.
2. Use one of the SHM formulae to calculate the maximum speed of the swing.
3. Now use the centripetal resultant force to get to the tension.
The swing is at Whinlatter, so next time you go...