For those not familiar with the area, the Menai Straits are between the Island of Angelsey and mainland Wales. Although the tidal currents in the Straits, under the Menai Bridge can reach 2m/s (4 knots.), the area where the plane was last reported is much wider, so the currents would be less.
The flight last went over what is known as the Great Orme, which is a dramatic rocky headland 679 feet high. A few minutes later it pitched downwards towards Puffin Island.
It has been reported that some wreckage has been found, but the present choppy state of the sea, and the foggy visibility, is not helping with the search.
.