Shuttlecraft Goddard, from the 6th season episode "Relics".
About this creation
This shuttle design replaced the Type 7, a larger, rounder craft that proved difficult to build at full size. Since the mock up and miniature didn't match, it was used less and less and eventually only in close-ups with an actor's head.
The Type 6 was rebuilt from the Type 4 that appeared once in Star Trek V. The middle section with side hatches was removed, the warp nacelles were changed, and the livery was updated.
The aft ramp is the only entry point, with an updated interior.
"Hey! What are you thinking? I can't pilot this thing without a roof!"