Drilling rig

A method for drilling with a plurality of lengths of drilling string by a drilling rig comprising a mast with an upper and a lower end, a hoist, and a rotatable drillhead assembly, comprising:

• rotating said rotatable drillhead assembly to a horizontal position;
• positioning a length of said string in said drill head assembly;
• rotating said drillhead assembly and said length of string to a vertical position;
• raising said drillhead assembly to said upper end on said mast by said hoist;
• drilling said length of string into the ground by said drillhead assembly as said hoist lowers said drillhead assembly to said lower end of said mast;
• holding said length of string by a break-out tool assembly mounted on said lower end of said mast;
• repeating with a second length of string the steps of rotating said drillhead assembly to said horizontal position, positioning said second length of said string in said drillhead assembly, and rotating said drillhead assembly to said vertical position;
• and
• rotating said second length of string by said break-out tool assembly until said second length of string is secured to said length of string.

An improved drilling rig, comprising:

• a mast having an upper end and a lower end;
• a hoist assembly positioned at said top end of said mast;
• one or more cable return assemblies positioned at said bottom end of said mast;
• and
• a drillhead assembly;
• said drillhead assembly being hung by one or more cables threaded from said hoist assembly to said drillhead assembly and from said drillhead assembly to said one or more cable return assemblies and back to said hoist assembly;
• said cables being counter-wound on said hoist assembly such that said cables roll off of said hoist assembly in the direction towards said drillhead assembly at the same rate said cables are pulled onto said hoist assembly from the direction towards said one or more cable return assemblies.