04930586 is referenced by 29 patents and cites 10 patents.

Hydraulic drilling method and apparatus in which the drilling fluid itself is utilized to control the direction in which a hole is bored in the earth. The orientation of the drill head is monitored by tilt and roll sensors, and the discharge of drilling fluid through radially or obliquely directed nozzles is controlled by poppet valves in accordance with the orientation to control the direction in which the hole is cut.

Title
Hydraulic drilling apparatus and method
Application Number
7/351244
Publication Number
4930586
Application Date
May 12, 1989
Publication Date
June 5, 1990
Inventor
Rowe Hakes
Bakersfield
CA, US
Robert D Wilkes Jr
Berkeley
CA, US
Paul S Turin
Berkeley
CA, US
Agent
Flehr Hohbach Test Albritton & Herbert
Assignee
Robert Wayne Dickinson
CA, US
Ben Wade Oakes Dickinson III
CA, US
IPC
E21B 47/024
E21B 7/18
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