Narrative:

We were cleared into las vegas mccarran airport via the TYSSN3 arrival. During the arrival we were clear directly to shand intersection. Enroute to shand; we were subsequently cleared for the visual approach to 25L. During this visual approach the weather conditions were clear; very clear; and visibilities were unlimited. It was one of the clearest nights that I can ever remember. The lights of the city; the airport; all appropriate approach lighting systems including PAPI were clearly visible; as well as all terrain in the area. It was such a clear night that there was virtually nothing that was not observable. Right after we were cleared for the visual approach I set 3;800 in the altitude window to match the altitude for the final approach fix; relin. It was here that my first officer; being the pilot flying (PF); started a slow descent and direct routing for relin. Sometime during the slow descent I asked the PF to level off momentarily to avoid a terrain warning. Unfortunately; I asked him to level off just a split second too late and we received an 'ever so momentary' terrain warning. Because it was night when the momentary terrain warning was received; PF immediately started to execute the terrain avoidance maneuver. No sooner had he started to execute the maneuver; the terrain warning disappeared. It's important to emphasize that at no time was the terrain not in sight; and at no time was situational awareness lost. Once the terrain warning went away; PF reestablished a normal visual approach and landing to mccarran airport; landing on runway 25L.

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Original NASA ASRS Text

Title: An aircraft descended on a visual approach and received a GPWS alert.

Narrative: We were cleared into Las Vegas McCarran Airport via the TYSSN3 arrival. During the arrival we were clear directly to SHAND intersection. Enroute to SHAND; we were subsequently cleared for the visual approach to 25L. During this visual approach the weather conditions were clear; very clear; and visibilities were unlimited. It was one of the clearest nights that I can ever remember. The lights of the city; the airport; all appropriate approach lighting systems including PAPI were clearly visible; as well as all terrain in the area. It was such a clear night that there was virtually nothing that was not observable. Right after we were cleared for the visual approach I set 3;800 in the altitude window to match the altitude for the final approach fix; RELIN. It was here that my FO; being the Pilot Flying (PF); started a slow descent and direct routing for RELIN. Sometime during the slow descent I asked the PF to level off momentarily to avoid a terrain warning. Unfortunately; I asked him to level off just a split second too late and we received an 'ever so momentary' terrain warning. Because it was night when the momentary terrain warning was received; PF immediately started to execute the terrain avoidance maneuver. No sooner had he started to execute the maneuver; the terrain warning disappeared. It's important to emphasize that at no time was the terrain not in sight; and at no time was situational awareness lost. Once the terrain warning went away; PF reestablished a normal visual approach and landing to McCarran Airport; landing on Runway 25L.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.