bottom 44 which it passes through this rod 46 being terminated at its end outside the casing 43 by a ring 47 which an operator can manipulate in order to extract the pin 22 from the aperture in the arm 35 by pulling on the said ring 47 to compress the spring 45 by the pin 42 on the alighting area 2 there is also disposed a marking which visibly delineates the periphery of a circle 49 with a diameter of about 7 m centered on a point lying between the two guide rails 5 and 6 on the line 50 midway between the said two rails the marking also delineates on this alighting and take off area 2 two lines for alignment 48 disposed at roughly 25 u00b0 from the said median line 50 such a maneuvering device is used in the way that will now be described in fig1 to 6 has been represented more especially the transfer of the helicopter from its alighting area 2 to its hangar 4 it is seen particularly in fig1 that the helicopter h alights on the alighting area 2 aligning itself along the axis of the ship or along one of the marking lines 48 the pilot 39 s seat being approximately above the periphery of the circle 49 the wheels 21 of the forward undercarriage then being locked in the axis of the helicopter h in calm seas the pilot has the possibility of making his.