Drilling derrick and apparatus base assembly

An improved portable drilling apparatus for drilling a vertical or horizontal oil or gas well using a vertical derrick with a top drive drilling and fluid assembly mounted upon a trailer which includes a trailer bed supported upon a trailer frame and defines a flat profile rear end, with a cabling system mounted upon said trailer bed, said improved portable drilling apparatus comprising:

• an improved rear base frame member defining a pair of vertical rear support columns with an upper end providing an upper plate and a pivotal mounting flange;
• a lower derrick mast pivotally attached to said pivotal mounting flanges by pins, said lower derrick mast defining a pair of parallel rear legs attached together with secondary support members and a pair of shorter parallel front legs attached by secondary support members to each respective rear leg, with an area between each front leg open, wherein said front legs and rear legs define a channel;
• a pair of diagonal A-frame support members respectively attached to each rear leg extending away from each front leg, each diagonal A-frame support member having a lower end;
• at least one primary hydraulic ram attached between said lower derrick mast and said trailer frame to elevate and lower said lower derrick mast from a horizontal transport position to a vertical operational position;
• a pair of A-frame support stanchions pivotally attached to said trailer frame which are raised into a support position below each lower end of each respective diagonal A-frame support member to lock said lower derrick mast into said vertical operational position;
• and
• an upper derrick mast slidably engaged within said channel of said lower derrick mast, said upper derrick mast defining two parallel rear legs attached together by secondary support members, and a pair of front legs of equal length to said rear legs, each front leg attached to a respective rear leg by additional secondary support members with an area between said pair of front legs open, wherein said rear legs and front legs of said upper derrick mast also forming a channel.