After an evening visit to the Briarbank micro-brewery in Ipswich, and a morning cleaning the boat (unrelated!) our friend Jo joined us at lunchtime. We then left fox's marina and sailed back down the river, tacking down the narrow channel past Pin Mill and turned back into the Stour to anchor for another night and to be ready to head off first thing on Wednesday.

We were leaving early to catch as much of a lift from the tide as possible - and were blessed with dry weather with good visibility and even quite a lot of sun.

Crossing the Thames Estuary is far more complicated than any other estuary we've crossed. It means avoiding shipping, sandbanks, traffic schemes and now wind farms.

In fact our chosen path took us through Foulgars Gap which involves going through the corner of the London Array wind farm. The top of our mast is some 19m above sea level, and according to the documentation the base of all the blades is a minimum of 22m above the highest possible tide. So we should have at least 3m clearance. As it happens we weren't going too close to any turbine to test this - but simply looking at them it was hard to believe that our mast wasn't taller than the bottom of the blades.

We did most of the passage under the cruising chute, but switched to the main sail whilst in the wind farm for better visibility and as we'd turned into the wind a bit more for that segment.