Wing sail

A handheld wing sail comprising:

• a sailcloth (2) supported on frame members (3a, 3b, 4, 5, 6a, 6b, 7a, 7b), the frame members comprising two mast tubes (3a and 3b) positioned in a V shape defining a nose angle (.alpha.) and opposite respective tips (14a), a boom (4) located in the area between the mast tubes, the boom being curved at the symmetry plane of the wing sail and connected to each mast tube (3a and 3b) by supporting tubes (6a, 6b), which are at one end fastened to the boom (4) by a connection member (10) and at the opposite end to the respective mast tubes (3a and 3b) by connection means (20a, 20b), and a traverse tube (5) joining the mast tubes (3a, 3b) together and fastened to the mast tubes by connection pieces (15a, 15b), wherein the mast tubes (3a, 3b) and the boom (4) are connected to each other by a nose link (9), which comprises a threadlike connection member (37), which is made of flexible but substantially non-stretchable material for making it possible to change the nose angel (.alpha.) and to fold the mast tubes (3a, 3b) toward the boom (4), whereby to bring the wing sail into a folded position for turning the mast tubes (3a, 3b) and the boom (4) freely in different directions when the wing sail is in the folded position and, thus, ready for transport, the tips (14a) of the mast tubes (3a, 3b) have, at tips (19a, 19b) of the sailcloth (2), flexible antenna portions (7a, 7b) to which are connected tightening means (8a, 8b) for keeping the wing sail taut during sailing, the boom (4) is curved in such a way that its maximum distance (X) from the sailcloth (2) is 25 to 50 cm at the symmetry plane of the wing sail, and the distance between the connection member (10) and the nose link (9) is 20 to 50% of the boom (4) length.