Abstract: An AGHV comprising a chassis 10 having front 11, 12 and rear 15, 16 wheels thereon, a support platform 25, 26 being movably mounted on the chassis 10 and jib 30 being provided on the chassis 10 for loading the nosewheels of an aircraft onto the platform 25, 26; said platform 25, 26 being longitudinally movable between the first position wherein said nose wheels can be loaded thereon so as to be supported by the platform 25, 26 on the chassis 10 and a second position which is clear of said first position.

Abstract: The plough consists of two portions separable by rams (72). Each portion comprises a beam (14, 16) joined to a plough body part (18, 20). The portions include two pairs of longitudinally-spaced arms (69) interconnected by pivots (70). At each end of the plough a support including bearers (61) is closed by a ram (59) to entrap the pipeline (26). Another ram lifts the support to raise the pipeline between the plough body parts (18, 20). The support ram is connected to a pressurized accumulator so that the support rollers (62) are kept against the pipeline (26) as the plough rises and falls and pitches. The elevated positions of the arms (69) and the relatively short separation between the two pairs of arms (69) allows the plough to descend and pitch relatively to the pipeline. In a modification the two beams are joined by rigid bridging structure and the plough body parts are pivotally connected to their respective beams. In other modifications the supports are dispensed with; or only one is used.

Abstract: A pipeline trenching plough is towed along the seabed by a tow wire (20) connected to a ship or tractor. The course of the plough is changed or maintained by oppositely-acting forces imposed on the wire (20) and on the body (10) of the plough by a hydraulic ram (24). The offset angle between the wire (20) and the lengthwise direction (30) of the plough is monitored by a potentiometer (33, 35). The wire (20) is connected to the plough at a real hitch point (22) vertically above the center of resistance (23) of soil forces on the ploughshare (12) and landside (14). Under normal equilibrium conditions the forces from the ram are zero. The forces required to change the course are small and independent of the offset angle. Ram force can counteract a side-sloping seabed. In modifications, the wire (20) is connected to a virtual hitch point formed by an adjustable linkage; or by a carriage adjustable along a transverse beam.

Abstract: A self-loading plough assembly comprises a plough (2) having a channel (16) for the passage of a cable or pipe (8) and a cutter or cutters (5) for cutting and lifting a wedge of material from a substrate to form a trench into which the cable or pipe (8) is laid. The assembly also comprises a jib (11) for supporting the plough (2) and a carrier (7) for supporting the jib (11). The plough (2) is rotatably mounted under the jib (11) and the jib (11) is slideably mounted on the carrier (7) in such manner that the jib (11) can be raised or lowered and the plough (2) can be rotated about a horizontal axis to scoop the cable or pipe (8) into the channel (16).The assembly can pick up cable or pipe from the ground, e.g., the sea bed, and load it into the plough without manual intervention for burial, and reverse the procedure if need be.