I will deign 4 layers pcb board

It is about a small research vessel with an open working main deck (aft from frame 20). Frame space is 650 mm. Double bottom is at 800 mm above base, lower deck is at 2850 mm above base, Main deck is at 5300 mm above bas and finally bridge deck is at 7800 mm above base and it is 2600 mm high. Fr 13-22 there are 2 Fuel Oil tanks extending from -3500 mm to 3500 mm accross centerline. Tanks are from double bottom to lower deck. From fr 15 onwards there will be the retractable fins, no details yet of reaction forces but for now let's