The aircraft was being taxied on a confined apron when it collided with a concrete tie-down block. Earlier in the morning another aircraft was parked on the apron and tied to the block. That aircraft was subsequently moved into an adjacent hangar by aircraft maintenance personnel, but they neglected to remove the tie-down block. The pilot reported that he did not notice the tie-down block, which was similiarly coloured to the apron surface. His attention was apparently diverted to maintaining wingtip clearance from five other aircraft parked around the perimeter of the apron.
