Abstract: The present invention relates to an anchor system which includes an anchor projectile section having an anchor body, beams pivotally connected at their lower end to the body and interconnected by flexible segments, a pressure storage or launching section having a launching tube in which the upper body of the projectile section is positioned for being launched therefrom, a drag plate secured around the launching section with substantial weight therein and sufficient diameter to create a large virtual water mass and hydrodynamic drag to resist upward movement of the launching section when the anchor projectile section is released for launching into the sea bottom, a remotely controlled collet connector securing the anchor projectile section within the launching section until the anchor is to be launched for setting in the bottom.

Abstract: A flotation riser having a series of annular chambers with a riser string extending in free-standing relation through said chambers, means for supplying gas to the chambers to control buoyancy, means to supply gas to a plurality of the lowermost chambers to provide an emergency supply of deballasting gas, and means for remotely releasing said supply of gas into the chambers above to render the flotation riser free-standing to permit release from the floating platform during emergencies. A method of storing emergency deballasting gas and for emergency deballasting of the chambers to render the flotation riser freee-standing including the steps of supplying gas to the lowermost chambers, retaining the gas in said lowermost chambers, and remotely releasing the gas and conducting it to higher chamber to deballast such chambers sufficient so that said flotation riser is free-standing.

Abstract: A riser structure for connecting from a floating structure to a subsea wellhead for drilling or production which has an upper flexible steel section and a lower flexible section connecting from the wellhead to the upper steel section, the lower section, cantilevered from the wellhead, having an increasing flexibility in the upward direction and having a greater flexibility near its upper connection than the upper section. The lower section is preferably of a more flexible material, such as titanium, with a thinner wall at its upper end than at the lower end.