Narrative:

First officer flying. I accepted visual approach behind 737 to oak runway 29. Scattered layer of clouds beneath us on final approach did not allow us to keep continuous contact with the runway. Kept preceding aircraft in sight until he penetrated clouds approximately 1100 ft AGL. Approach light pier visible through break in clouds. Runway threshold visible intermittently. First officer descended below the glidepath in an attempt to fly through a break in the clouds underneath us and keep the runway in sight. Seeing this was going to be difficult; first officer advised that I ask for clearance for the ILS runway 29. Thinking this may not be necessary I elected not to ask the approach controller for the ILS. Very shortly thereafter; it became apparent to me we were not going to be able to remain clear of clouds on the visual. Just then; norcal approach control instructed me to contact oak tower. I should have asked for a last second clearance for the ILS but hesitated and did not. Upon contacting oak tower I - again - should have asked for an ILS clearance but; fearing the tower would not be able to grant this request; I did not ask. We penetrated clouds and went IMC for about 10 seconds. After exiting the clouds the runway environment was clearly in sight and we landed without incident.

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Original NASA ASRS Text

Title: Airline crew on a Runway 29 visual approach to OAK entered IMC and failed to request an ILS approach because they did not anticipate being in the clouds.

Narrative: First Officer flying. I accepted visual approach behind 737 to OAK Runway 29. Scattered layer of clouds beneath us on final approach did not allow us to keep continuous contact with the runway. Kept preceding aircraft in sight until he penetrated clouds approximately 1100 FT AGL. Approach light pier visible through break in clouds. Runway threshold visible intermittently. First Officer descended below the glidepath in an attempt to fly through a break in the clouds underneath us and keep the runway in sight. Seeing this was going to be difficult; First Officer advised that I ask for clearance for the ILS Runway 29. Thinking this may not be necessary I elected not to ask the Approach Controller for the ILS. Very shortly thereafter; it became apparent to me we were not going to be able to remain clear of clouds on the visual. Just then; NORCAL Approach Control instructed me to contact OAK Tower. I should have asked for a last second clearance for the ILS but hesitated and did not. Upon contacting OAK Tower I - again - should have asked for an ILS clearance but; fearing the Tower would not be able to grant this request; I did not ask. We penetrated clouds and went IMC for about 10 seconds. After exiting the clouds the runway environment was clearly in sight and we landed without incident.

Data retrieved from NASA's ASRS site as of April 2012 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.