A TB-20 Trinidad's landing gear failed to extend normal. The pilot declared an emergency and landed normally.

Narrative

On final approach into ZZZ after an uneventful 1.3 hour night flight; attempted to extend landing gear and saw only two gear-down indications instead of three. Recycled gear with same result. Informed tower; and asked to fly the pattern while attempting to troubleshoot. Verified all three indicators lamps OK (test button); and attempted several more cycles; plus performed manual extension procedure; with same result. Accepted tower's offer for a fly-by for visual inspection; but darkness prevented a good observation. A police helicopter was maneuvering nearby and offered to inspect the gear visually. I did NOT accept this offer; remembering an incident in 1991 in which a similar offer resulted in two aircraft destroyed and 7 fatalities. (NTSB Identification: DCA91MA031B). Requested emergency equipment be made available; and attempted landing; which was completed successfully. Taxied to tie-down; and completed paperwork with fire truck operator. This is the second time exactly this incident has taken place in this same aircraft; though the first time it was daylight. That time; the issue was identified as a lubrication problem and repaired locally. This time; my intent is to bring the plane to a manufacturer-approved service center to have the landing gear system rigorously inspected and repaired.