A flexible pipe system comprising: • an unbonded flexible pipe (15; 80; 90; 105, 106, 107, 108) comprising at least one armouring layer (31, 33, 34, 35) and being connected to a floating vessel (1; 131); • a sensor system adapted for detecting changes in strain and/or temperature in the unbonded flexible pipe and comprising: ∘ at least one optical fibre (41; 81, 82, 83, 84; 91) integrated in the at least one armouring layer (31, 33, 34, 35) of the unbonded flexible pipe (15; 80; 90; 105, 106, 107, 108); and ∘ interrogating equipment (20; 92; 120) having an optical transmitter (51; 95) configured to transmit optical signals into said at least one optical fibre (41; 81, 82, 83, 84; 91); and an optical detector (52; 96) configured to receive optical signals reflected from said at least one optical fibre (41; 81, 82, 83, 84; 91) and to detect therefrom at least one parameter in said unbonded flexible pipe (15; 80; 90; 105, 106, 107, 108); Characterized in that the flexible pipe system comprises • a turret (4; 104; 124; 134) for rotationally connecting the unbonded flexible pipe (15; 80; 90; 105, 106, 107, 108) to the floating vessel (1; 131), said turret (4; 104; 124; 134) being supported by a substantially vertical shaft (3; 133) in the floating vessel (1; 131) and comprising an end-fitting (16; 116) for terminating and securing said unbonded flexible pipe (15; 80; 90; 105, 106, 107, 108) to the turret (4; 104; 124; 134); and • a swivel device for rotationally connecting the turret (4; 104; 124; 134) to the shaft (3; 133) of the floating vessel (1; 131) and providing a fluid transfer passage between the turret (4; 104; 124; 134) and the floating vessel (1; 131), wherein said interrogating equipment (20; 92; 120) is located on said turret (4; 104; 124; 134) to provide that optical signals reflected from the fibre can reach the interrogating equipment without being distorted in the swivel device and is further configured to transfer signals indicative of said at least one detected parameter to receiving equipment on said floating vessel (1; 131) and wherein said interrogating equipment (20; 92; 120) comprises a transmitter for transmitting said signals indicative of said at least one detected parameter to the receiving equipment on said floating vessel (1; 131), and wherein the flexible pipe system is configured to transmit said signals as wireless signals. • an unbonded flexible pipe (15; 80; 90; 105, 106, 107, 108) comprising at least one armouring layer (31, 33, 34, 35) and being connected to a floating vessel (1; 131); • a sensor system adapted for detecting changes in strain and/or temperature in the unbonded flexible pipe and comprising: ∘ at least one optical fibre (41; 81, 82, 83, 84; 91) integrated in the at least one armouring layer (31, 33, 34, 35) of the unbonded flexible pipe (15; 80; 90; 105, 106, 107, 108); and ∘ interrogating equipment (20; 92; 120) having an optical transmitter (51; 95) configured to transmit optical signals into said at least one optical fibre (41; 81, 82, 83, 84; 91); and an optical detector (52; 96) configured to receive optical signals reflected from said at least one optical fibre (41; 81, 82, 83, 84; 91) and to detect therefrom at least one parameter in said unbonded flexible pipe (15; 80; 90; 105, 106, 107, 108); ∘ at least one optical fibre (41; 81, 82, 83, 84; 91) integrated in the at least one armouring layer (31, 33, 34, 35) of the unbonded flexible pipe (15; 80; 90; 105, 106, 107, 108); and ∘ interrogating equipment (20; 92; 120) having an optical transmitter (51; 95) configured to transmit optical signals into said at least one optical fibre (41; 81, 82, 83, 84; 91); and an optical detector (52; 96) configured to receive optical signals reflected from said at least one optical fibre (41; 81, 82, 83, 84; 91) and to detect therefrom at least one parameter in said unbonded flexible pipe (15; 80; 90; 105, 106, 107, 108); • a turret (4; 104; 124; 134) for rotationally connecting the unbonded flexible pipe (15; 80; 90; 105, 106, 107, 108) to the floating vessel (1; 131), said turret (4; 104; 124; 134) being supported by a substantially vertical shaft (3; 133) in the floating vessel (1; 131) and comprising an end-fitting (16; 116) for terminating and securing said unbonded flexible pipe (15; 80; 90; 105, 106, 107, 108) to the turret (4; 104; 124; 134); and • a swivel device for rotationally connecting the turret (4; 104; 124; 134) to the shaft (3; 133) of the floating vessel (1; 131) and providing a fluid transfer passage between the turret (4; 104; 124; 134) and the floating vessel (1; 131), wherein said interrogating equipment (20; 92; 120) is located on said turret (4; 104; 124; 134) to provide that optical signals reflected from the fibre can reach the interrogating equipment without being distorted in the swivel device and is further configured to transfer signals indicative of said at least one detected parameter to receiving equipment on said floating vessel (1; 131) and wherein said interrogating equipment (20; 92; 120) comprises a transmitter for transmitting said signals indicative of said at least one detected parameter to the receiving equipment on said floating vessel (1; 131), and wherein the flexible pipe system is configured to transmit said signals as wireless signals.