I used the cardboard box of the empennage as floor and put the left tank on the baffle (tank attach angles). Than I filled the tank through the fuel caps (with water).

After one hour of preparing the wing skins (deblueing the rivet strips). I found no droplets on the cardboard.

After removing the water (through the drain), I inspected the baffle and tank attach angles and found no leaks.

Next time we’re going to close the right wing tank.

Time: 5 Hours, Rivets: 0/0