Self-propelled deep well turbine drill

A self-propelled turbine drill apparatus for drilling well holes comprising:

• means clamping a first cylindrical end against a well casing wall, said first cylindrical end making up part of said turbine drill having clamping means therein, said first end being operably connected to and opposite to a second cylindrical end containing a cutter head assembly, said first and second ends being axially movable one from the other,
• means driving said cutter head assembly at said second end deeper into said well hole by extending said cutter head assembly axially from said clamped first cylindrical end,
• means clamping said cutter head assembly at said second cylindrical end near the end of said well hole when said cutter head assembly is advanced axially into said hole its maximum length, said means clamping said cutter head assembly is an underreamer section affixed to and axially in line with a base of said cutter head assembly, said underreamer section having expandable cutter arms equidistantly spaced around said underreamer section, said cutter arms expand out against said casing wall, thereby clamping said cutter head assembly near the bottom of the hold,
• means releasing said clamped first cylindrical end,
• means retracting said released first cylindrical end toward said cutter head assembly, and
• subsequently reclamping said first cylindrical end thereby initiating a subsequent turbine drill cycle thereby advancing said drill deeper into said hole after said cutter arms have been retracted in said underreamer section.