GPS mandatory for MSF ratification

Note GPS data is listed as a requirement. My Derwent River pilot does not carry one. Is it mandatory please?
Note GPS data is listed as a requirement. My Derwent River pilot does not carry one. Is it mandatory please?
Comments
You could use a smart phone (and/or gps watch on board the boat) to record the gps track. Best to have at least two going, in case one fails.
Here’s a useful discussion, complete with some suggestions for free tracking apps for smart phones
https://forum.marathonswimmers.org/discussion/1422/
Thanks @LakeBagger. I think I have a solution