No Aircraft
Air Traffic Control Fully Certified
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ATC Issue All Types
General None Reported / Taken
Procedure
I was in the Tower at or prior to opening. I noted that the weather was VFR; but with a fog bank along the shoreline and visibility to the south 1 mile; with patchy fog scattered elsewhere. The Supervisor came up to advise me that SBA primary and secondary RADAR would be released to maintenance for several hours. I pointed out the fog and let him know that with in the last hour the ASOS had been reporting VV001 and ¾ SM; and that I couldn't guarantee that the weather would stay VFR. Supervisor advised that the RADAR had to be released and that we wouldn't be losing the ILS. Within 1 hour we did become low IFR. Some aircraft would go missed approach. SBA was using multi mode. When SBA ASR does not contribute to the feed the multi mode performance is poor. Targets are intermittently lost and dropped below 6;000 MSL; especially at 2;000 when vectoring for ILS turn on. There are wide variations in target displacement. SBA is located in a coastal environment where the weather can be changeable; however; even at that we are still located in Southern California where the weather is great VFR 300+ days a year. Although this was one particular event; I have seen frequent poor decision making on the release of NAVAIDS; including RADAR. Decisions are made for the convenience of maintenance personnel without proper weight given to the safety of the flying public. For example fog usually burns off or lifts in the afternoon yet outages are scheduled to start in the morning because maintenance shifts start then and it gives them maximum time; convenient for maintenance personnel? Yes. The safest and most prudent decision when the weather will likely be better later? No; not at all; I would like to see good reasonable judgment used when making decisions to release equipment; with heavier weight given to safety.
SBA Controller voiced concern regarding the facilities equipment release to maintenance policy; alleging equipment release decisions are made to accommodate maintenance schedules rather that insuring the safety of the aviation users.