Narrative:

As I vectored an aircraft onto final just outside the outer marker; the tower called and told me they were going ATC 0 [facility unable to provide ATC services] for approximately 5 minutes due to staffing. Ont is supposed to be a 24 hour facility providing class C services. The aircraft was now cleared for the ILS approach and now had to go to advisory frequency. Not sure what the tower had going on; but this could have been very dangerous and confusing. I was confused myself thinking they had an equipment malfunction. It wasn't until later I was told the tower was understaffed and they may go ATC 0 at times and that all aircraft should be held until they reopened. Make sure all TRACON personnel are briefed on ont ATC 0 procedures. Fix staffing problems at this tower.

Google
 

Original NASA ASRS Text

Title: SCT TRACON Controller had an aircraft on an ILS approach to ONT when the Tower unexpectedly closed briefly due to lack of staffing.

Narrative: As I vectored an aircraft onto final just outside the outer marker; the Tower called and told me they were going ATC 0 [facility unable to provide ATC Services] for approximately 5 minutes due to staffing. ONT is supposed to be a 24 hour facility providing Class C services. The aircraft was now cleared for the ILS approach and now had to go to advisory frequency. Not sure what the tower had going on; but this could have been very dangerous and confusing. I was confused myself thinking they had an equipment malfunction. It wasn't until later I was told the Tower was understaffed and they may go ATC 0 at times and that all aircraft should be held until they reopened. Make sure all TRACON personnel are briefed on ONT ATC 0 procedures. Fix staffing problems at this Tower.

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.